# Prospects for Localization of Gravitational Wave Transients by the Advanced
LIGO and Advanced Virgo Observatories

J. Aasi1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
J. Abadie1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
B. P. Abbott1 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  R. Abbott1 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  T. D. Abbott2 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. Abernathy3 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  T. Accadia4 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  F. Acernese5ac 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  C. Adams6 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  T. Adams7 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  P. Addesso8 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  R. X. Adhikari1
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  C.
Affeldt9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  M. Agathos11a 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  O. D. Aguiar12 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  P. Ajith1 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  B. Allen9,13,10 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  A. Allocca14ac 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  E. Amador Ceron13 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  D. Amariutei15
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  S. B.
Anderson1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
W. G. Anderson13 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  K. Arai1 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. C. Araya1 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  C. Arceneaux16 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. Ast9,10 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. M. Aston6 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  P. Astone17a 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  D. Atkinson18 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  P. Aufmuth10,9
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  C.
Aulbert9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Austin1 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  B. E. Aylott19 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. Babak20 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  P. Baker21 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  G. Ballardin22 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  S. Ballmer23 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  Y. Bao15 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  J. C. Barayoga1
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D.
Barker18 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
F. Barone5ac 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  B. Barr3 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Barsotti24 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. Barsuglia25 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. A. Barton18 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  I. Bartos26 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  R. Bassiri3,27 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Bastarrika3 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. Basti14ab
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J.
Batch18 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
J. Bauchrowitz9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  Th. S. Bauer11a 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. Bebronne4 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  B. Behnke20 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  M. Bejger28c 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M.G. Beker11a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. S. Bell3 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  C. Bell3 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  G. Bergmann9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J. M.
Berliner18 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
A. Bertolini9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  J. Betzwieser6 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  N. Beveridge3 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  P. T. Beyersdorf29 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  T. Bhadbade27 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  I. A. Bilenko30
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  G.
Billingsley1 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  J. Birch6 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. Biscans24 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. Bitossi14a 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. A. Bizouard31a 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  E. Black1 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  J. K. Blackburn1 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  L. Blackburn32 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  D. Blair33 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  B. Bland18
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M.
Blom11a 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
O. Bock9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  T. P. Bodiya24 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  C. Bogan9,10 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  C. Bond19 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  F. Bondu34b 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  L. Bonelli14ab 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  R. Bonnand35 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  R. Bork1 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  M. Born9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  V. Boschi14a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  S. Bose36 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  L. Bosi37a 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  B. Bouhou25
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J.
Bowers2 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
C. Bradaschia14a 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  P. R. Brady13 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  V. B. Braginsky30 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. Branchesi38ab 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  J. E. Brau39 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  J. Breyer9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  T.
Briant40 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
D. O. Bridges6 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  A. Brillet34a 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. Brinkmann9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  V. Brisson31a 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. Britzger9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  A. F. Brooks1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  D. A. Brown23
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D. D.
Brown19 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
F. Brueckner19 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  K. Buckland1 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  T. Bulik28b 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  H. J. Bulten11ab 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  A. Buonanno41 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  J. Burguet–Castell42 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  D. Buskulic4 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  C. Buy25 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  R. L. Byer27
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  L.
Cadonati43 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
G. Cagnoli35,44 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  E. Calloni5ab 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  J. B. Camp32 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  P. Campsie3 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  K. Cannon45 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  B. Canuel22 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  J. Cao46 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  C. D. Capano41
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  F.
Carbognani22 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Carbone19 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  S. Caride47 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  A. D. Castiglia48 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. Caudill13 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. Cavaglià16 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  F. Cavalier31a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  R. Cavalieri22
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  G.
Cella14a 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
C. Cepeda1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
E. Cesarini49a 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  T. Chalermsongsak1 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  S. Chao101 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  P. Charlton50 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  E. Chassande-Mottin25 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  X. Chen33 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  Y. Chen51 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  A. Chincarini52 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. Chiummo22
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  H. S.
Cho53 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J.
Chow54 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  N.
Christensen55 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  Q. Chu33 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. S. Y. Chua54 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  C. T. Y. Chung56 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  G. Ciani15 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  F. Clara18 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  D. E. Clark27 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  J. A. Clark43 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  F. Cleva34a 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  E. Coccia49ab
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  P.-F.
Cohadon40 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
C. N. Colacino14ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  A. Colla17ab 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  M. Colombini17b 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. Constancio Jr.12 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  A. Conte17ab 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  D. Cook18 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  T. R. Corbitt2 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Cordier29 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  N. Cornish21
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  A.
Corsi103 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
C. A. Costa2,12 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. Coughlin57 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  J.-P. Coulon34a 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. Countryman26 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  P. Couvares23 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  D. M. Coward33
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M.
Cowart6 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
D. C. Coyne1 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  K. Craig3 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  J. D. E. Creighton13 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  T. D. Creighton44 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  A. Cumming3 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  L. Cunningham3 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  E. Cuoco22 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  K. Dahl9,10 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  M. Damjanic9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  S. L.
Danilishin33 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. D’Antonio49a 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  K. Danzmann9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  V. Dattilo22 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  B. Daudert1 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  H. Daveloza44 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Davier31a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  G. S. Davies3
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  E. J.
Daw58 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  T.
Dayanga36 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
R. De Rosa5ab 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  G. Debreczeni59 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  J. Degallaix35 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  W. Del Pozzo11a 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  E. Deleeuw15 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  T. Denker10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  T. Dent9,10 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  V. Dergachev1
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  R.
DeRosa2 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
R. DeSalvo8 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. Dhurandhar60 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  L. Di Fiore5a 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  A. Di Lieto14ab 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  I. Di Palma9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  A. Di Virgilio14a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. Díaz44 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. Dietz4,16
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  F.
Donovan24 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
K. L. Dooley9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  S. Doravari1 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  M. Drago61ab 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. Drasco20 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  R. W. P. Drever62 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  J. C. Driggers1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  Z. Du46 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  J.-C. Dumas33
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  S.
Dwyer24 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
T. Eberle9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  M. Edwards7 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  A. Effler2 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  P. Ehrens1 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. S. Eikenberry15 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  G. Endrőczi59 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  R. Engel1 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  R. Essick24 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  T. Etzel1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  K. Evans3 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. Evans24 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  T. Evans6 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  M.
Factourovich26 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  V. Fafone49ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  S. Fairhurst7 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  Q. Fang33 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  B. F. Farr63 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  W. Farr63 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. Favata13 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  D. Fazi63 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  H. Fehrmann9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  D. Feldbaum15 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  I. Ferrante14ab
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  F.
Ferrini22 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
F. Fidecaro14ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  L. S. Finn64 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  I. Fiori22 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  R. P. Fisher23 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  R. Flaminio35 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  S. Foley24 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  E. Forsi6 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  L. A. Forte5a
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  N.
Fotopoulos1 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  J.-D. Fournier34a 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  J. Franc35 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. Franco31a 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. Frasca17ab 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  F. Frasconi14a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. Frede9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M. A.
Frei48 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  Z.
Frei65 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  A.
Freise19 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
R. Frey39 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
T. T. Fricke9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  D. Friedrich9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  P. Fritschel24 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  V. V. Frolov6 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M.-K. Fujimoto66 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  P. J. Fulda15
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M. Fyffe6
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J. Gair57
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M.
Galimberti35 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Gammaitoni37ab 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  J. Garcia18 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  F. Garufi5ab 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. E. Gáspár59 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  N. Gehrels32 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  G. Gelencser65
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  G.
Gemme52 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
E. Genin22 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
A. Gennai14a 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Á. Gergely67 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  S. Ghosh36 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  J. A. Giaime2,6 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. Giampanis13 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  K. D. Giardina6 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  A. Giazotto14a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  S. Gil-Casanova42
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  C. Gill3
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J.
Gleason15 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
E. Goetz9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  G. González2 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  N. Gordon3 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  M. L. Gorodetsky30 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. Gossan51 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. Goßler9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  R. Gouaty4 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  C. Graef9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  P. B.
Graff32 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
M. Granata35 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  A. Grant3 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. Gras24 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  C. Gray18 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  R. J. S. Greenhalgh68 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  A. M. Gretarsson69 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  C. Griffo70 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  H. Grote9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  K. Grover19 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  S. Grunewald20
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  G. M.
Guidi38ab 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
C. Guido6 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
E. K. Gustafson1 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  R. Gustafson47 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  D. Hammer13 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  G. Hammond3 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  J. Hanks18 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  C. Hanna71 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  J. Hanson6 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  K. Haris72
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J.
Harms62 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
G. M. Harry73 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  I. W. Harry23 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  E. D. Harstad39 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. T. Hartman15 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  K. Haughian3 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  K. Hayama66 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  J. Heefner1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. Heidmann40
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M. C.
Heintze6 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
H. Heitmann34a 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  P. Hello31a 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  G. Hemming22 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  M. A. Hendry3 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  I. S. Heng3 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  A. W. Heptonstall1 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Heurs9,10 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. Hewitson9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  S. Hild3
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D. Hoak43
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  K. A.
Hodge1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  K.
Holt6 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M.
Holtrop74 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
T. Hong51 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
S. Hooper33 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  J. Hough3 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  E. J. Howell33 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  V. Huang101 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  E. A. Huerta23 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  B. Hughey69 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. H. Huttner3 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Huynh13 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  T. Huynh–Dinh6
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D. R.
Ingram18 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
R. Inta54 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
T. Isogai24 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  A. Ivanov1 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  B. R. Iyer75 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  K. Izumi66 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. Jacobson1 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  E. James1 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  H. Jang76 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  Y. J. Jang63 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  P. Jaranowski28d 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  E. Jesse69 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  W. W. Johnson2
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D.
Jones18 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
D. I. Jones77 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  R. Jones3 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  R.J.G. Jonker11a 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  L. Ju33 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  P. Kalmus1 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  V. Kalogera63 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. Kandhasamy78 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  G. Kang76 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  J. B. Kanner32 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Kasprzack22,31a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  R. Kasturi79
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  E.
Katsavounidis24 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  W. Katzman6 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  H. Kaufer9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  K. Kawabe18 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. Kawamura66 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  F. Kawazoe9,10 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  D. Keitel9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D.
Kelley23 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
W. Kells1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
D. G. Keppel9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  A. Khalaidovski9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  F. Y. Khalili30 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  E. A. Khazanov80 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  B. K. Kim76 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  C. Kim76 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  K. Kim81 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  N. Kim27 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  Y. M. Kim53 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  P. J. King1
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D. L.
Kinzel6 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
J. S. Kissel24 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. Klimenko15 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  J. Kline13 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  K. Kokeyama2 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  V. Kondrashov1 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. Koranda13 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  W. Z. Korth1 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  I. Kowalska28b 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  D. Kozak1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  C. Kozameh82
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  A.
Kremin78 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
V. Kringel9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  B. Krishnan10,9 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  A. Królak28ae 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  C. Kucharczyk27 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  G. Kuehn9,10 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  P. Kumar23 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  R. Kumar3 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  B. J. Kuper70 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  R. Kurdyumov27
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  P. Kwee24
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M.
Landry18 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
B. Lantz27 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
P. D. Lasky56 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  C. Lawrie3 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  A. Lazzarini1 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  A. Le Roux6 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  P. Leaci20 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  C. H. Lee53 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  H. K. Lee81 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  H. M. Lee83 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  J. Lee70 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  J. R. Leong9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  N.
Leroy31a 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
N. Letendre4 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  B. Levine18 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  V. Lhuillier18 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  T. G. F. Li11a 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  A. C. Lin27 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  V. Litvine1 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  Y. Liu46 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  Z. Liu15 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  N. A. Lockerbie84 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  D. Lodhia19 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  K. Loew69 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  J. Logue3 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  A. L.
Lombardi41 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
M. Lorenzini49ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  V. Loriette31b 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. Lormand6 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  G. Losurdo38a 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  J. Lough23 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. Lubinski18
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  H.
Lück9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
A. P. Lundgren9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  J. Macarthur3 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  E. Macdonald7 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  B. Machenschalk9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. MacInnis24 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  D. M. Macleod7
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  F.
Magana-Sandoval70 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. Mageswaran1 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  K. Mailand1 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  E. Majorana17a 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  I. Maksimovic31b 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  V. Malvezzi49a
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  N. Man34a
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  G.
Manca20 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
I. Mandel19 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  V. Mandic78 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. Mantovani14a 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  F. Marchesoni37ac 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  F. Marion4 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  S. Márka26 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  Z. Márka26 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. Markosyan27
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  E. Maros1
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J.
Marque22 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
F. Martelli38ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  I. W. Martin3 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  R. M. Martin15 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  D. Martonov1 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  J. N. Marx1 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  K. Mason24 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. Masserot4
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  F.
Matichard24 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Matone26 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  R. A. Matzner85 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  N. Mavalvala24 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  G. May15 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  G. Mazzolo9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  K. McAuley29 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  R. McCarthy18
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D. E.
McClelland54 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. C. McGuire86 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  G. McIntyre1 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  J. McIver43 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  G. D. Meadors47 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. Mehmet9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  J. Meidam11a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  T. Meier10,9
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  A.
Melatos56 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
G. Mendell18 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  R. A. Mercer13 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  S. Meshkov1 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  C. Messenger7 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. S. Meyer6 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  H. Miao51 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  C. Michel35 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  L. Milano5ab 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  J. Miller54 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  Y. Minenkov49a
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  C. M. F.
Mingarelli19 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. Mitra60 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  V. P. Mitrofanov30 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  G. Mitselmakher15 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  R. Mittleman24 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  B. Moe13 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Mohan22 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  S. R. P.
Mohapatra23,48 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  F. Mokler10,9 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  D. Moraru18 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  G. Moreno18 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  N. Morgado35 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  T. Mori66 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. R. Morriss44 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  K. Mossavi9,10 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  B. Mours4 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  C. M.
Mow–Lowry9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  C. L. Mueller15 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  G. Mueller15 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  S. Mukherjee44 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  A. Mullavey2,54 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  J. Munch87 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  D. Murphy26 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  P. G. Murray3 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. Mytidis15
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D. Nanda
Kumar15 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
T. Nash1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
L. Naticchioni17ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  R. Nayak88 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  V. Necula15 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  I. Neri37ab 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  G. Newton3 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  T. Nguyen54 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  E. Nishida66 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. Nishizawa66
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  A. Nitz23
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  F.
Nocera22 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
D. Nolting6 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  M. E. Normandin44 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  L. Nuttall7 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  E. Ochsner13 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  J. O’Dell68 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  E. Oelker24 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  G. H. Ogin1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  J. J. Oh89 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  S. H. Oh89
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  F. Ohme7
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  P.
Oppermann9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  B. O’Reilly6 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  R. O’Shaughnessy13 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  C. Osthelder1 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  C. D. Ott51 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  D. J. Ottaway87 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  R. S. Ottens15 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  J. Ou101 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  H. Overmier6
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  B. J.
Owen64 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  C.
Padilla70 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
A. Page19 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
A. Pai72 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
L. Palladino49ac 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  C. Palomba17a 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  Y. Pan41 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  C. Pankow13 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  F. Paoletti14a,22 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  R. Paoletti14ac 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. A. Papa20,13
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  H.
Paris18 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
M. Parisi5ab 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  W. Parkinson90 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  A. Pasqualetti22 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  R. Passaquieti14ab 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  D. Passuello14a 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Pedraza1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  S. Penn79 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  C. Peralta20
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  A.
Perreca23 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
M. Phelps1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
M. Pichot34a 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  M. Pickenpack9,10 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  F. Piergiovanni38ab 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  V. Pierro8 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  L. Pinard35 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  I. M. Pinto8 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Pitkin3 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  H. J. Pletsch9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  R.
Poggiani14ab 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  J. Pöld9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  F. Postiglione91 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  C. Poux1 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  V. Predoi7 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  T. Prestegard78 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  L. R. Price1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. Prijatelj9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  S.
Privitera1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
G. A. Prodi61ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  L. G. Prokhorov30 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  O. Puncken44 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. Punturo37a 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  P. Puppo17a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  V. Quetschke44
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  E.
Quintero1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
R. Quitzow-James39 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  F. J. Raab18 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  D. S. Rabeling11ab 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  I. Rácz59 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  H. Radkins18 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  P. Raffai26 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  S. Raja92 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  M. Rakhmanov44 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  C. Ramet6 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  P. Rapagnani17ab 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  V. Raymond1 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  V. Re49ab 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  C. M. Reed18
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  T. Reed93
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  T.
Regimbau34a 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. Reid94 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  D. H. Reitze1 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  F. Ricci17ab 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  R. Riesen6 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  K. Riles47 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. Roberts27 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  N. A. Robertson1,3 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  F. Robinet31a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  E. L. Robinson20
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  A.
Rocchi49a 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
S. Roddy6 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
C. Rodriguez63 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Rodriguez85 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. Rodruck18 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  L. Rolland4 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  J. G. Rollins1 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  J. D. Romano44 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  R. Romano5ac 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  J. H. Romie6
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D.
Rosińska28cf 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  C. Röver9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  S. Rowan3 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  A. Rüdiger9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  P. Ruggi22 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  K. Ryan18 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  F. Salemi9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  L. Sammut56 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  V. Sandberg18
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J.
Sanders47 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
S. Sankar24 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  V. Sannibale1 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  L. Santamaría1 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  I. Santiago-Prieto3 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  E. Saracco35 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  B. Sassolas35 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  B. S. Sathyaprakash7 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  P. R. Saulson23
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  R. L.
Savage18 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
R. Schilling9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  R. Schnabel9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  R. M. S. Schofield39 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  D. Schuette9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  B. Schulz9,10 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  B. F. Schutz20,7
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  P.
Schwinberg18 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  J. Scott3 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. M. Scott54 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  F. Seifert1 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  D. Sellers6 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  A. S. Sengupta95 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  D. Sentenac22 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  A. Sergeev80 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  D. A. Shaddock54
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  S. Shah96
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M.
Shaltev9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  Z. Shao1 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  B. Shapiro27 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  P. Shawhan41 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  D. H. Shoemaker24 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  T. L Sidery19 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  X. Siemens13 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  D. Sigg18 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  D. Simakov9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  A. Singer1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  L. Singer1 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  A. M. Sintes42
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  G. R.
Skelton13 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
B. J. J. Slagmolen54 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  J. Slutsky9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  J. R. Smith70 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. R. Smith1 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  R. J. E. Smith19 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  N. D. Smith-Lefebvre1 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  E. J. Son89
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  B.
Sorazu3 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
T. Souradeep60 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Sperandio49ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. Stefszky54 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  E. Steinert18 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  J. Steinlechner9,10 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  S. Steinlechner9,10 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  S. Steplewski36
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D.
Stevens63 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
A. Stochino54 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  R. Stone44 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  K. A. Strain3 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. E. Strigin30 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  A. S. Stroeer44 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  R. Sturani38ab 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  A. L. Stuver6
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  T. Z.
Summerscales97 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. Susmithan33 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  P. J. Sutton7 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  B. Swinkels22 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  G. Szeifert65 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Tacca22 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  L. Taffarello61c
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  D.
Talukder39 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
D. B. Tanner15 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. P. Tarabrin9,10 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  R. Taylor1 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  A. P. M. ter Braack11a 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  M. Thomas6 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  P. Thomas18 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  K. A. Thorne6
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  K. S.
Thorne51 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
E. Thrane1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
V. Tiwari15 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  K. V. Tokmakov84 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  C. Tomlinson58 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  A. Toncelli14ab 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. Tonelli14ab 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  O. Torre14ac 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  C. V. Torres44
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  C. I.
Torrie1,3 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
E. Tournefier4 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  F. Travasso37ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  G. Traylor6 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  M. Tse26 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  D. Ugolini98 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  C. S. Unnikrishnan99 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  H. Vahlbruch10,9 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  G. Vajente14ab 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. Vallisneri51
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J. F. J.
van den Brand11ab 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  C. Van Den Broeck11a 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. van der Putten11a 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  M. V. van der Sluys63 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  A. A. van Veggel3 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  S. Vass1 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. Vasuth59 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  R. Vaulin24
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M.
Vavoulidis31a 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  A. Vecchio19 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  G. Vedovato61c 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  J. Veitch7 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  K. Venkateswara100 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  D. Verkindt4 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  S. Verma33 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  F. Vetrano38ab
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  A.
Viceré38ab 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
R. Vincent-Finley86 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  J.-Y. Vinet34a 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  S. Vitale24 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. Vitale11a 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  T. Vo18 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  H. Vocca37a 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  C. Vorvick18 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  W. D. Vousden19
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  S. P.
Vyatchanin30 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  A. Wade54 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Wade13 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  M. Wade13 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  S. J. Waldman24 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  L. Wallace1 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  Y. Wan46 1LIGO - California Institute of Technology, Pasadena,
CA 91125, USA  J. Wang101 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  M. Wang19 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  X. Wang46 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  A. Wanner9,10 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  R. L. Ward25,54 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Was9,10,31a 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  M. Weinert9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  A. J.
Weinstein1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
R. Weiss24 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
T. Welborn6 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  L. Wen33 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  P. Wessels9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. West23 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  T. Westphal9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  K. Wette9,10 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  J. T. Whelan48 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  D. J. White58 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  B. F. Whiting15
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  K.
Wiesner9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  C. Wilkinson18 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  P. A. Willems1 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  L. Williams15 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  R. Williams1 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  T. Williams90 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  J. L. Willis102 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  B. Willke9,10
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  M.
Wimmer9,10 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
L. Winkelmann9,10 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  W. Winkler9,10 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  C. C. Wipf24 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  A. G. Wiseman13 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  H. Wittel9,10 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  G. Woan3 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  R. Wooley6 1LIGO
- California Institute of Technology, Pasadena, CA 91125, USA  J. Worden18
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  J.
Yablon63 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
I. Yakushin6 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  H. Yamamoto1 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  C. C. Yancey41 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  H. Yang51 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  D. Yeaton-Massey1 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  S. Yoshida90 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  H. Yum63 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  M. Yvert4 1LIGO - California Institute
of Technology, Pasadena, CA 91125, USA  A. Zadrożny28e 1LIGO - California
Institute of Technology, Pasadena, CA 91125, USA  M. Zanolin69 1LIGO -
California Institute of Technology, Pasadena, CA 91125, USA  J.-P. Zendri61c
1LIGO - California Institute of Technology, Pasadena, CA 91125, USA  F.
Zhang24 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
L. Zhang1 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
C. Zhao33 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
H. Zhu64 1LIGO - California Institute of Technology, Pasadena, CA 91125, USA
X. J. Zhu33 1LIGO - California Institute of Technology, Pasadena, CA 91125,
USA  N. Zotov93 1LIGO - California Institute of Technology, Pasadena, CA
91125, USA  M. E. Zucker24 1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA  J. Zweizig1 1LIGO - California Institute of
Technology, Pasadena, CA 91125, USA  (The LIGO Scientific Collaboration and
the Virgo Collaboration)  1LIGO - California Institute of Technology,
Pasadena, CA 91125, USA

###### Abstract

We present a possible observing scenario for the Advanced LIGO and Advanced
Virgo gravitational wave detectors over the next decade, with the intention of
providing information to the astronomy community to facilitate planning for
multi-messenger astronomy with gravitational waves. We determine the expected
sensitivity of the network to transient gravitational-wave signals, and study
the capability of the network to determine the sky location of the source. For
concreteness, we focus primarily on gravitational-wave signals from the
inspiral of binary neutron star (BNS) systems, as the source considered likely
to be the most common for detection and also promising for multimessenger
astronomy. We find that confident detections will likely require at least 2
detectors operating with BNS sensitive ranges of at least 100 Mpc, while
ranges approaching 200 Mpc should give at least $\sim$1 BNS detection per year
even under pessimistic predictions of signal rates. The ability to localize
the source of the detected signals depends on the geographical distribution of
the detectors and their relative sensitivity, and can be as large as thousands
of square degrees with only 2 sensitive detectors operating. Determining the
sky position of a significant fraction of detected signals to areas of 5 deg2
to 20 deg2 will require at least 3 detectors of sensitivity within a factor of
$\sim$ 2 of each other and with a broad frequency bandwidth. Should one of the
LIGO detectors be relocated in India as expected, many gravitational-wave
signals will be localized to a few square degrees by gravitational-wave
observations alone.

##  1 Introduction

Advanced LIGO (aLIGO) [1] and Advanced Virgo (AdV) [2, 3] are kilometer-scale
gravitational wave (GW) detectors that are expected to yield direct
observations of gravitational waves. In this document we describe the
currently projected schedule, sensitivity, and sky localization accuracy for
the GW detector network. The purpose of this document is to provide
information to the astronomy community to assist in the formulation of plans
for the upcoming era of GW observations. In particular, we intend this
document to provide the information required for assessing the features of
programs for joint observation of GW events using electromagnetic, neutrino,
or other observing facilities.

The full science of aLIGO and AdV is broad [4], and is not covered in this
document. We concentrate solely on candidate GW transient signals. We place
particular emphasis on the coalescence of neutron-star binary systems, which
are the GW source with the most reliable predictions on the prospects of
detection.

Although our collaborations have amassed a great deal of experience with GW
detectors and analysis, it is still very difficult to make predictions for
both improvements in search methods and for the rate of progress for detectors
which are not yet fully installed or operational. We stress that the scenarios
of LIGO and Virgo detector sensitivity evolution and observing times given
here represent our best estimates at present. They should not be considered as
fixed or firm commitments. As the detectors’ construction and commissioning
progresses, we intend to release updates versions of this document.

##  2 Commissioning and Observing Phases

We divide the roadmap for the aLIGO and AdV observatories into three phases:

  1. 1.

Construction includes the installation and testing of the detectors. This
phase ends with acceptance of the detectors. Acceptance means that the
interferometers can lock for periods of hours: light is resonant in the arms
of the interferometer with _no guaranteed gravitational-wave sensitivity._
Construction will likely involve several short engineering runs with no
expected astrophysical output as the detectors progress towards acceptance.

  2. 2.

Commissioning will take the detectors from their configuration at acceptance
through progressively better sensitivity to the ultimate second-generation
detector sensitivity. Engineering and science runs in the commissioning phase
will allow us to understand our detectors and analyses in an observational
mode. It is expected that science runs will produce astrophysical results,
including upper limits on the rate of sources and quite possibly the first
detections of GWs. During this phase, exchange of GW candidates with partners
outside the LSC and Virgo collaborations will be governed by memoranda of
understanding (MOUs) [5].

  3. 3.

Observing runs begin when the detectors are at a sensitivity which makes
detections likely. We anticipate that there will be a gradual transition from
the commissioning to the observing phases. If it has not happened previously,
the first few GW signals will be observed and the LSC and Virgo will be
engaged in a long-term campaign to observe the GW sky. After the first four
detections [5] we expect free exchange of GW event candidates with the
astronomical community and the maturation of GW astronomy.

The progress in sensitivity as a function of time will affect the duration of
the runs that we plan at any stage, as we strive to minimize the time to the
first gravitational wave detection. Commissioning is a complex process which
involves both scheduled improvements to the detectors and tackling unexpected
new problems. While our experience makes us cautiously optimistic regarding
the schedule for the advanced detectors, we note that we are targeting an
order of magnitude improvement in sensitivity relative to the previous
generation of detectors over a much wider frequency band. Consequently it is
not possible to make concrete predictions for sensitivity as a function of
time. We can, however, use our previous experience as a guide to plausible
scenarios for the detector operational states that will allow us to reach the
desired sensitivity. Unexpected problems could slow down the commissioning,
but there is also the possibility that progress may happen faster than
predicted here. As the detectors begin to be commissioned, information on the
cost in time and benefit in sensitivity will become more apparent and drive
the schedule of runs. More information on event rates, including the first
detection, will also very likely change the schedule and duration of runs. In
section 2.1 we present the commissioning plans for the aLIGO and AdV
detectors. A summary of expected science runs is in section 2.2.

###  2.1 Commissioning and Observing Roadmap

The anticipated strain sensitivity evolution for aLIGO and AdV is shown in
Fig. 1. A standard figure of merit for the sensitivity of an interferometer is
the binary neutron star (BNS) range: the volume- and orientation-averaged
distance at which a compact binary coalescence consisting of two
$\mathrm{1.4\,M_{\odot}}$ neutron stars gives a matched filter signal-to-noise
ratio of 8 in a single detector [6]111 Another often quoted number is the BNS
_horizon_ —the distance at which an optimally oriented and located BNS system
would be observed with a signal to noise ratio of 8. The horizon is a factor
of 2.26 larger than the range. . The BNS ranges for the various stages of
aLIGO and AdV expected evolution are also provided in Fig. 1.

Figure 1:  aLIGO (left) and AdV (right) target strain sensitivity as a
function of frequency. The average distance to which binary neutron star (BNS)
signals could be seen is given in Mpc. Current notions of the progression of
sensitivity are given for early, middle, and late commissioning phases, as
well as the final design sensitivity target and the BNS-optimized sensitivity.
While both dates and sensitivity curves are subject to change, the overall
progression represents our best current estimates.

The installation of aLIGO is well underway. The plan calls for three identical
4 km interferometers, referred to as H1, H2, and L1. In 2011, the LIGO Lab and
IndIGO consortium in India proposed installing one of the aLIGO Hanford
detectors, H2, at a new observatory in India (LIGO-India). As of early 2013
LIGO Laboratory has begun preparing the H2 interferometer for shipment to
India. Funding for the Indian portion of LIGO-India is in the final stages of
consideration by the Indian government.

The first aLIGO science run is expected in 2015. It will be of order three
months in duration, and will involve the H1 and L1 detectors (assuming H2 is
placed in storage for LIGO-India). The detectors will _not_ be at full design
sensitivity; we anticipate a possible BNS range of 40 – 80 Mpc. Subsequent
science runs will have increasing duration and sensitivity. We aim for a BNS
range of 80 – 170 Mpc over 2016–18, with science runs of several months.
Assuming that no unexpected obstacles are encountered, the aLIGO detectors are
expected to achieve a 200 Mpc BNS range circa 2019. After the first observing
runs, circa 2020, it might be desirable to optimize the detector sensitivity
for a specific class of astrophysical signals, such as BNSs. The BNS range may
then become 215 Mpc. The sensitivity for each of these stages is shown in Fig.
1.

Because of the planning for the installation of one of the LIGO detectors in
India, the installation of the H2 detector has been deferred. This detector
will be reconfigured to be identical to H1 and L1 and will be installed in
India once the LIGO-India Observatory is complete. The final schedule will be
adopted once final funding approvals are granted. It is expected that the site
development would start in 2014, with installation of the detector beginning
in 2018. Assuming no unexpected problems, first runs are anticipated circa
2020 and design sensitivity at the same level as the H1 and L1 detectors is
anticipated for no earlier than 2022.

The commissioning timeline for AdV [3] is still being defined, but it is
anticipated that in 2015 AdV might join the LIGO detectors in their first
science run depending on the sensitivity attained. Following an early step
with sensitivity corresponding to a BNS range of 20 – 60 Mpc, commissioning is
expected to bring AdV to a 60 – 85 Mpc in 2017–18. A configuration upgrade at
this point will allow the range to increase to approximately 65 – 115 Mpc in
2018–20. The final design sensitivity, with a BNS range of 130 Mpc, is
anticipated circa 2021. The corresponding BNS-optimised range would be 145
Mpc. The sensitivity curves for the various AdV configurations are shown in
Fig. 1.

The GEO600 [7] detector will likely be operational in the early to middle
phase of the AdV and aLIGO science runs, i.e. from 2015–2017. The sensitivity
that potentially can be achieved by GEO in this timeframe is similar to the
AdV sensitivity of the early and mid scenarios at frequencies around 1 kHz and
above. Around 100 Hz GEO will be at least 10 times less sensitive than the
early AdV and aLIGO detectors.

Japan has recently begun the construction of an advanced detector, KAGRA [8].
KAGRA is designed to have a BNS range comparable to AdV at final sensitivity.
While we do not consider KAGRA in this document, we note that the addition of
KAGRA to the worldwide GW detector network will improve both sky coverage and
localization capabilities beyond those envisioned here.

###  2.2 Estimated observing schedule

Keeping in mind the mentioned important caveats about commissioning affecting
the scheduling and length of science runs, the following is a plausible
scenario for the operation of the LIGO-Virgo network over the next decade:

  * •

2015: A 3 month run with the two-detector H1L1 network at early aLIGO
sensitivity (40 – 80 Mpc BNS range). Virgo in commissioning at $\sim$ 20 Mpc
with a chance to join the run.

  * •

2016–17: A 6 month run with H1L1 at 80 – 120 Mpc and Virgo at 20 – 60 Mpc.

  * •

2017–18: A 9 month run with H1L1 at 120 – 170 Mpc and Virgo at 60 – 85 Mpc.

  * •

2019+: Three-detector network with H1L1 at full sensitivity of 200 Mpc and V1
at 65 – 130 Mpc.

  * •

2022+: Four-detector H1L1V1+LIGO-India network at full sensitivity (aLIGO at
200 Mpc, AdV at 130 Mpc).

The observational implications of this scenario are discussed in section 4.

##  3 Searches for gravitational-wave transients

Data from gravitational wave detectors are searched for many types of possible
signals [4]. Here we focus on signals from compact binary coalescences (CBC),
including BNS systems, and on generic transient or burst signals. See [9, 10,
11] for recent observational results from LIGO and Virgo for such systems.

The gravitational waveform from a binary neutron star coalescence is well
modelled and matched filtering can be used to search for signals and measure
the system parameters. For systems containing black holes, or in which the
component spin is significant, uncertainties in the waveform model can reduce
the sensitivity of the search. Searches for bursts make few assumptions on the
signal morphology, using time-frequency decompositions to identify
statistically significant excess power transients in the data. Burst searches
generally perform best for short-duration signals ($\lesssim$1 s); their
astrophysical targets include core-collapse supernovae, magnetar flares, black
hole binary coalescence, cosmic string cusps, and possibly as-yet-unknown
systems.

In the era of advanced detectors, the LSC and Virgo will search in near real-
time for CBC and burst signals for the purpose of rapidly identifying event
candidates. A prompt notice of a potential GW transient by LIGO-Virgo might
enable followup observations in the electromagnetic spectrum. A first followup
program including low-latency analysis, event candidate selection, position
reconstruction and the sending of alerts to several observing partners
(optical, X-ray, and radio) was implemented and exercised during the 2009–2010
LIGO-Virgo science run [12, 13, 14]. Latencies of less than 1 hour were
achieved and we expect to improve this in the advanced detector era. Increased
detection confidence, improved sky localization, and identification of host
galaxy and redshift are just some of the benefits of joint GW-electromagnetic
observations. With this in mind, we focus on two points of particular
relevance for followup of GW events: the source localization afforded by a GW
network and the relationship between signal significance (or false alarm rate)
and localization.

###  3.1 Localization

The aLIGO-AdV network will determine the sky position of a GW transient source
mainly by triangulation using the observed time delays between sites [15, 16].
The effective single-site timing accuracy is approximately

$\sigma_{t}=\frac{1}{2\pi\rho\sigma_{f}}\,,$ (1)

where $\rho$ is the signal-to-noise ratio in the given detector and
$\sigma_{f}$ is the effective bandwidth of the signal in the detector,
typically of order $100$ Hz. Thus a typical timing accuracy is on the order of
$10^{-4}$ s (about $1/100$ of the light travel time between sites). This sets
the localization scale. Equation (1) ignores many other relevant issues such
as uncertainty in the emitted gravitational waveform, instrumental calibration
accuracies, and correlation of sky location with other binary parameters [15,
17, 18, 19, 20, 21]. While many of these will affect the measurement of the
time of arrival in individual detectors, such factors are largely common
between two similar detectors, so the time difference between the two
detectors is relatively uncorrelated with these “nuisance” parameters. The
triangulation approach therefore provides a good leading order estimate to
localizations.

Source localization using only timing for a 2-site network yields an annulus
on the sky; see Fig. 2. Additional information such as signal amplitude, spin,
and precessional effects can sometimes resolve this to only parts of the
annulus, but even then sources will only be localized to regions of hundreds
to thousands of square degrees. For three detectors, the time delays restrict
the source to two sky regions whose locations are mirror images in the plane
formed by the three detectors. It is often possible to eliminate one of these
regions by requiring consistent amplitudes in all detectors. For signals just
above the detection threshold, this typically yields regions with areas of
several tens of square degrees. If there is significant difference in
sensitivity between detectors, the source is less well localized and we may be
left with the majority of the annulus on the sky determined by the two most
sensitive detectors. With four or more detectors, timing information alone is
sufficient to localize to a single sky region, and the additional baselines
help to limit the region to under 10 square degrees for some signals.

Figure 2:  Source localization by triangulation for the aLIGO-AdV network. The
locus of constant time delay (with associated timing uncertainty) between two
detectors forms an annulus on the sky concentric about the baseline between
the two sites. For three detectors, these annuli may intersect in two
locations. One is centered on the true source direction, $S$, while the other
($S^{\prime}$) is its mirror image with respect to the geometrical plane
passing through the three sites. For four or more detectors there is a unique
intersection region of all of the annuli. Figure adapted from [22].

From (1), it follows that the linear size of the localization ellipse scales
inversely with the signal to noise ratio (SNR) of the signal and the frequency
bandwidth of the signal in the detector. For GWs that sweep across the band of
the detector, such as binary merger signals, the effective bandwidth is $\sim
100$ Hz, determined by the most sensitive frequencies of the detector. For
shorter transients the bandwidth $\sigma_{f}$ depends on the specific signal.
For example, GWs emitted by various processes in core-collapse supernovae are
anticipated to have relatively large bandwidths, between 150-500 Hz [23, 24,
25, 26], largely independent of detector configuration. By contrast, the sky
localization region for narrowband burst signals may consist of multiple
disconnected regions; see for example [27, 12].

Finally, we note that some GW searches are triggered by electromagnetic
observations, and in these cases localization information is known a priori.
For example, in GW searches triggered by gamma-ray bursts [10] the triggering
satellite provides the localization. The rapid identification of a GW
counterpart to such a trigger could prompt further followups by other
observatories. This is of particular relevance to binary mergers, which are
considered the likely progenitors of most short gamma-ray bursts. It is
therefore important to have high-energy satellites operating during the
advanced detector era.

Finally, it is also worth noting that all GW data are stored permanently, so
that it is possible to perform retroactive analyses at any time.

###  3.2 Detection and False Alarm Rates

The rate of BNS coalescences is uncertain, but is currently predicted to lie
between $10^{-8}-10^{-5}$ Mpc-3 yr-1 [28]. This corresponds to between 0.4 and
400 signals above SNR 8 per year of observation for a single aLIGO detector at
final sensitivity [28]. The predicted observable rates for NS-BH and BBH are
similar. Expected rates for other transient sources are lower and/or less well
constrained.

The rate of false alarm triggers above a given SNR will depend critically upon
the data quality of the advanced detectors; non-stationary transients or
glitches will produce an elevated background of loud triggers. For low-mass
binary coalescence searches, the waveforms are well modelled and signal
consistency tests reduce the background significantly. For burst sources which
are not well modelled, or which spend only a short time in the detectors’
sensitive band, it is more difficult to distinguish between the signal and a
glitch, and so a reduction of the false alarm rate comes at a higher cost in
terms of reduced detection efficiency.

Figure 3: False alarm rate versus detection statistic for CBC and burst
searches on 2009-2010 LIGO-Virgo data. Left: Cumulative rate of background
events for the CBC search, as a function of the threshold ranking statistic
$\rho_{c}$ [9]. Right: Cumulative rate of background events for the burst
search, as a function of the coherent network amplitude $\eta$ [11]. In the
large-amplitude limit $\eta$ is related to the combined SNR by
$\rho_{c}\sim\sqrt{2K}\eta$, where $K$ is the number of detectors. The burst
events are divided into two sets based on their central frequency.

Figure 3 shows the noise background as a function of detection statistic for
the low-mass binary coalescence and burst searches with the 2009–2010 LIGO-
Virgo data [9, 11]. For binary mergers, the background rate decreases by a
factor of $\sim$100 for every unit increase in combined SNR $\rho_{c}$, with
no evidence of a tail even at low false alarm rates. Here, $\rho_{c}$ is a
combined, re-weighted SNR. The re-weighting is designed to reduce the SNR of
glitches while leaving signals largely unaffected. Consequently, for a signal
$\rho_{c}$ is essentially the root-sum-square of the SNRs in the individual
detectors.

We conservatively estimate a $\rho_{c}$ threshold of 12 is required for a
false rate below $\sim$ $10^{-2}$ yr-1 in aLIGO-AdV, where we have taken into
account trials factors due to the increase in the number of template waveforms
required to search the advanced detector data. In future sections, we quote
results for this threshold. A combined SNR of 12 corresponds to a single
detector SNR of 8.5 in each of two detectors or 7 in three detectors. At this
threshold we estimate approximately a quarter of detected signals can be
localized with 90% containment to areas of 20 deg2 or less by the H1L1V1
network at design sensitivity; see the 2019$+$ epoch in Table 1 for details.
For a background rate of 1 yr-1 (100 yr-1) the threshold $\rho_{c}$ decreases
by about 10% (20%), the number of signals above threshold increases by about
30% (90%), and the area localization for these low-threshold signals is
degraded by approximately 20% (60%).

Imperfections in the data can have a greater effect on the burst search. At
frequencies above 200 Hz the rate of background events falls off steeply as a
function of amplitude. At lower frequencies, however, the data often exhibit a
significant tail of loud background events that are not removed by multi-
detector consistency tests. While the extent of these tails varies, when
present they typically begin at rates of approximately 1 yr-1, hindering the
confident detection of low-frequency gravitational-wave transients. Although
the advanced detectors are designed with many technical improvements, we must
anticipate that burst searches will likely still have to deal with such tails
in some cases, particularly at low frequencies. The unambiguous observation of
an electromagnetic counterpart could increase the detection confidence in
these cases.

A study [27] of the localization capability of the burst search for the aLIGO-
AdV network using a variety of waveform morphologies finds that at an SNR of
$\rho_{c}\simeq 17$ (false rate of $\lesssim 0.1$ yr-1 from Fig. 3) the
typical error box area for 50% (90%) containment is approximately 40 deg2 (400
deg2). The median 50% containment area increases to 100 deg2 at
$\rho_{c}\simeq 12$, and drops to approximately 16 deg2 at $\rho_{c}\simeq
25$. These results are broadly consistent with a study of two burst detection
algorithms using real LIGO-Virgo data from 2009 [12], which shows that for
signals near the nominal search threshold (coherent network amplitude
$\eta\gtrsim 6$, corresponding $\rho_{c}\gtrsim 15$ [11]) median containment
regions are typically between 30 deg2 and 200 deg2, dropping to approximately
10 deg2 at large amplitudes. See Fig. 4 for an example.

Figure 4:  (left) Plot of typical uncertainty region sizes for the burst
search, as a function of GW strain amplitude at Earth, for a mix of ad hoc
Gaussian, sine-Gaussian, and broadband white-noise burst waveforms [12]. The
“searched area” is the area of the skymap with a likelihood value greater than
the likelihood value at the true source location. The solid line represents
the median (50%) performance, while the upper and lower limits of the shaded
area show the 75% and 25% quartile values. The detection threshold of
$\eta~{}\simeq 6$ corresponds to signal root-sum-square amplitudes
($h_{\mathrm{rss}}^{2}=\int[h_{+}^{2}+h_{\times}^{2}]dt$) of approximately
$h_{\text{rss}}\sim 0.5\times 10^{-21}\,\text{Hz}^{-1/2}$ to $\sim 2\times
10^{-21}\,\text{Hz}^{-1/2}$ [11], depending on signal frequency. Median
uncertainty regions at these amplitudes are typically between 30 deg2 and 200
deg2. (right) Typical uncertainty region sizes for two specific signal models:
short-duration Gaussian-modulated sinusoids (sine-Gaussians) with central
frequency 153 Hz or 1053 Hz and bandwidths of 17 Hz or 117 Hz. The larger-
bandwidth signal is more precisely localized, as expected from the discussion
in Sect. 3.1. See [12] for more details.

##  4 Observing Scenario

In this section we estimate the sensitivity, possible number of detections,
and localization capability for each of the observing scenarios laid out in
section 2.2. We discuss each future science run in turn and also summarize the
results in Table 1.

We estimate the expected number of binary neutron star coalescence detections
using both the lower and upper estimates on the BNS source rate density,
$10^{-8}-10^{-5}$ Mpc-3 yr-1 [28]. Similar estimates may be made for neutron
star – black hole (NS-BH) binaries using the fact that the NS-BH range is
approximately a factor of 2 larger222This assumes a black hole mass of
$10\,M_{\odot}$. than the BNS range, though the uncertainty in the NS-BH
source rate density is slightly larger [28]. We assume a nominal $\rho_{c}$
threshold of 12, at which the expected false alarm rate is $10^{-2}$ yr-1.
However, such a stringent threshold may not be appropriate for selecting
candidates triggers for electromagnetic followup. For example, selecting CBC
candidates at thresholds corresponding to a higher background rate of 1 yr-1
(100 yr-1) would increase the number of true signals subject to
electromagnetic followup by about 30% (90%). The area localization for these
low-threshold signals is only fractionally worse than for the high-threshold
population – by approximately 20% (60%). The localization of NS-BH signals is
expected to be similar to that of BNS signals.

For typical burst sources the GW waveform is not well known. However, the
performance of burst searches is largely independent of the detailed waveform
morphology [11], allowing us to quote an approximate sensitive range
determined by the total energy $E_{\mathrm{GW}}$ emitted in GWs, the central
frequency $f_{0}$ of the burst, the detector noise spectrum $S(f_{0})$, and
the single-detector SNR threshold $\rho_{\mathrm{det}}$ [29]:

$D\simeq\left(\frac{G}{2\pi^{2}c^{3}}\frac{E_{\mathrm{GW}}}{S(f_{0})f_{0}^{2}\rho_{\mathrm{det}}^{2}}\right)^{\frac{1}{2}}\,.$

In this document we quote ranges using $E_{\mathrm{GW}}=10^{-2}M_{\odot}c^{2}$
and $f_{0}=150$ Hz. We note that $E_{\mathrm{GW}}=10^{-2}M_{\odot}c^{2}$ is an
optimistic value for GW emission by various processes (see e.g. [10]); for
other values the distance reach scales as $E_{\mathrm{GW}}^{1/2}$. We use a
single-detector SNR threshold of 8, corresponding to a typical $\rho_{c}\simeq
12$ and false alarm rates of $\sim$0.3 yr-1. Due to the tail of the low-
frequency background-rate-vs.-amplitude distribution in Fig. 3, we see that
varying the selection threshold from a background of $0.1$ yr-1
($\rho_{c}\gtrsim 15$) to even 3 yr-1 ($\rho_{c}\gtrsim 10$) would increase
the number of true signals selected for electromagnetic followup by a factor
$(15/10)^{3}\sim 3$, though the area localization for low-SNR bursts may be
particularly challenging.

The run durations discussed below are in calendar time. Based on prior
experience, we can reasonably expect a duty cycle of $\sim$80% for each
instrument after a few science runs. Assuming downtime periods are
uncorrelated among detectors, this means 50% coincidence time in a 3-detector
network. Our estimates of expected number of detections account for these duty
cycles. They also account for the uncertainty in the detector sensitive ranges
as indicated in Fig. 1.

###  4.1 2015 run: aLIGO 40 – 80 Mpc, AdV 20 Mpc

This is envisioned as the first advanced detector science run, lasting three
months. The aLIGO sensitivity is expected to be similar to the “early” curve
in Fig. 1, with a BNS range of 40 – 80 Mpc and a burst range of 40 – 60 Mpc.
The Virgo detector will be in commissioning, but may join the run with a
$\sim$ 20 Mpc BNS range.

A three month run gives a BNS search volume333 The search volume is ${4\over
3}\pi R^{3}\times T$, where $R$ is the range and $T$ the observing time. of
$(0.4-3)\times 10^{5}$ Mpc3 yr at the confident detection threshold of
$\rho_{c}=12$. We therefore expect $0.0004-3$ BNS detections. A detection is
likely only if the most optimistic astrophysical rates hold.

With the 2-detector H1-L1 network any detected events would not be well
localized, and even if AdV joins the run this will continue to be the case due
to its lower sensitivity. Follow-up observations of a GW signal would
therefore likely rely on localizations provided by another instrument, such as
a gamma-ray burst satellite.

###  4.2 2016–17 run: aLIGO 80 – 120 Mpc, AdV 20 – 60 Mpc

This is envisioned to be a six month run with three detectors. The aLIGO
performance is expected to be similar to the “mid” curve in Fig. 1, with a BNS
range of 80 – 120 Mpc and a burst range of 60 – 75 Mpc. The AdV range may be
similar to the “early” curve, approximately 20 – 60 Mpc for BNS and 20 – 40
Mpc for bursts. This gives a BNS search volume of $(0.6-2)\times 10^{6}$ Mpc3
yr, and an expected number of $0.006-20$ BNS detections. Source localization
for various points in the sky for CBC signals for the 3-detector network is
illustrated in Fig. 5.

###  4.3 2017–18 run: aLIGO 120 – 170 Mpc, AdV 60 – 85 Mpc

This is envisioned to be a nine month run with three detectors. The aLIGO
(AdV) sensitivity will be similar to the “late” (“mid”) curve of Fig. 1, with
BNS ranges of 120 – 170 Mpc and 60 – 85 Mpc respectively and burst ranges of
75 – 90 Mpc and 40 – 50 Mpc respectively. This gives a BNS search volume of
$(3-10)\times 10^{6}$ Mpc3 yr, and an expected $0.04-100$ BNS detections.
Source localization for CBC signals is illustrated in Fig. 5. While the
greater range compared to the 2016–17 run increases the expected number of
detections, the detector bandwidths are marginally smaller. This slightly
degrades the localization capability for a source at a fixed signal-to-noise
ratio.

###  4.4 2019+ run: aLIGO 200 Mpc, AdV 65 – 130 Mpc

At this point we anticipate extended runs with the detectors at or near design
sensitivity. The aLIGO detectors are expected to have a sensitivity curve
similar to the “design (2019)” curve of Fig. 1. AdV may be operating similarly
to the “late” curve, eventually reaching the “design” sensitivity c.2021. This
gives a per-year BNS search volume of $2\times 10^{7}$ Mpc3 yr, giving an
expected (0.2 - 200) confident BNS detections annually. Source localization
for CBC signals is illustrated in Fig. 5. The fraction of signals localized to
areas of a few tens of square degrees is greatly increased compared to
previous runs. This is due to the much larger detector bandwidths,
particularly for AdV; see Fig. 1.

###  4.5 2022+ run: aLIGO (including India) 200 Mpc, AdV 130 Mpc

The four-site network incorporating LIGO-India at design sensitivity will have
both improved sensitivity and better localization capabilities. The per-year
BNS search volume increases to $4\times 10^{7}$ Mpc3 yr, giving an expected
$0.4-400$ BNS detections annually. Source localization is illustrated in Fig.
5. The addition of a fourth detector site allows for good source localization
over the whole sky.

Figure 5:  Network sensitivity and localization accuracy for face-on BNS systems with advanced detector networks. The ellipses show 90% confidence localization areas, and the red crosses show regions of the sky where the signal would not be confidently detected. The top two plots show the localization expected for a BNS system at 80 Mpc by the HLV network in the 2016–17 run (left) and 2017–18 run (right). The bottom two plots show the localization expected for a BNS system at 160 Mpc by the HLV network in the 2019+ run (left) and by the HILV network in 2022+ with all detectors at final design sensitivity (right). The inclusion of a fourth site in India provides good localization over the whole sky.  | Estimated | $E_{\mathrm{GW}}=10^{-2}M_{\odot}c^{2}$ |  | Number | % BNS Localized
---|---|---|---|---|---
| Run | Burst Range (Mpc) | BNS Range (Mpc) | of BNS | within
Epoch | Duration | LIGO | Virgo | LIGO | Virgo | Detections | $5\deg^{2}$ | $20\deg^{2}$
2015 | 3 months | 40 – 60 | – | 40 – 80 | – | 0.0004 – 3 | – | –
2016–17 | 6 months | 60 – 75 | 20 – 40 | 80 – 120 | 20 – 60 | 0.006 – 20 | 2 | 5 – 12
2017–18 | 9 months | 75 – 90 | 40 – 50 | 120 – 170 | 60 – 85 | 0.04 – 100 | 1 – 2 | 10 – 12
2019+ | (per year) | 105 | 40 – 80 | 200 | 65 – 130 | 0.2 – 200 | 3 – 8 | 8 – 28
2022+ (India) | (per year) | 105 | 80 | 200 | 130 | 0.4 – 400 | 17 | 48
Table 1:  Summary of a plausible observing schedule, expected sensitivities,
and source localization with the advanced LIGO and Virgo detectors, which will
be strongly dependent on the detectors’ commissioning progress. The burst
ranges assume standard-candle emission of $10^{-2}M_{\odot}c^{2}$ in GWs at
150 Hz and scale as $E_{\mathrm{GW}}^{1/2}$. The burst and binary neutron star
(BNS) ranges and the BNS localizations reflect the uncertainty in the detector
noise spectra shown in Fig. 1. The BNS detection numbers also account for the
uncertainty in the BNS source rate density [28], and are computed assuming a
false alarm rate of $10^{-2}$ yr-1. Burst localizations are expected to be
broadly similar to those for BNS systems, but will vary depending on the
signal bandwidth. Localization and detection numbers assume an 80% duty cycle
for each instrument.

##  5 Conclusions

We have presented a possible observing scenario for the Advanced LIGO and
Advanced Virgo network of gravitational wave detectors, with emphasis on the
expected sensitivities and sky localization accuracies. This network is
expected to begin operations in 2015. Unless the most optimistic astrophysical
rates hold, two or more detectors with an average range of at least 100 Mpc
and with a run of several months will be required for detection.

Electromagnetic followup of GW candidates may help confirm GW candidates that
would not be confidently identified from GW observations alone. However, such
follow-ups would need to deal with large position uncertainties, with areas of
many tens to thousands of square degrees. This is likely to remain the
situation until late in the decade. Optimizing the EM follow-up and source
identification is an outstanding research topic. Triggering of focused
searches in GW data by EM-detected events can also help in recovering
otherwise hidden GW signals.

Networks with at least 2 detectors with sensitivities of the order of 200 Mpc
are expected to yield detections with a year of observation based purely on GW
data even under pessimistic predictions of signal rates. Sky localization will
continue to be poor until a third detector reaches a sensitivity within a
factor of $\sim$ 2 of the others and with a broad frequency bandwidth. With a
four-site detector network at final design sensitivity, we may expect a
significant fraction of GW signals to be localized to as well as a few square
degrees by GW observations alone.

The purpose of this document is to provide information to the astronomy
community to facilitate planning for multi-messenger astronomy with advanced
gravitational-wave detectors. While the scenarios described here are our best
current projections, they will likely evolve as detector installation and
commissioning progresses. We will therefore update this document regularly.

The authors gratefully acknowledge the support of the United States National
Science Foundation for the construction and operation of the LIGO Laboratory,
the Science and Technology Facilities Council of the United Kingdom, the Max-
Planck-Society, and the State of Niedersachsen/Germany for support of the
construction and operation of the GEO600 detector, and the Italian Istituto
Nazionale di Fisica Nucleare and the French Centre National de la Recherche
Scientifique for the construction and operation of the Virgo detector. The
authors also gratefully acknowledge the support of the research by these
agencies and by the Australian Research Council, the International Science
Linkages program of the Commonwealth of Australia, the Council of Scientific
and Industrial Research of India, the Istituto Nazionale di Fisica Nucleare of
Italy, the Spanish Ministerio de Educación y Ciencia, the Conselleria
d’Economia Hisenda i Innovació of the Govern de les Illes Balears, the
Foundation for Fundamental Research on Matter supported by the Netherlands
Organisation for Scientific Research, the Polish Ministry of Science and
Higher Education, the FOCUS Programme of Foundation for Polish Science, the
Royal Society, the Scottish Funding Council, the Scottish Universities Physics
Alliance, The National Aeronautics and Space Administration, the Carnegie
Trust, the Leverhulme Trust, the David and Lucile Packard Foundation, the
Research Corporation, and the Alfred P. Sloan Foundation. This document has
been assigned LIGO Document number P1200087, Virgo Document number
VIR-0288A-12.

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