title: Update of the Search for the Neutrinoless Decay $\tau\to \mu\gamma$

abstract:
  We present an update of the search for the lepton family number violating
decay $\tau \to \mu\gamma$ using a complete CLEO II data sample of 12.6 million
$\tau^+\tau^-$ pairs. No evidence of a signal has been found and the
corresponding upper limit is $ \BR(\tau \to \mu\gamma) < 1.0 \times 10^{-6} $
at 90% CL, significantly smaller than previous limits. All quoted results are
preliminary.


title:
Measurement of the Spin-Density Matrix Elements in Exclusive
  Electroproduction of rho^0 Mesons at HERA

abstract:
  Exclusive electroproduction of rho^0 mesons has been measured using the ZEUS
detector at HERA in two Q^2 ranges, 0.25<Q^2<0.85 GeV^2 and 3<Q^2<30 GeV^2. The
low-Q^2 data span the range 20<W<90 GeV; the high-Q^2 data cover the 40<W<120
GeV interval. Both samples extend up to four-momentum transfers of |t|=0.6
GeV^2. The distribution in the azimuthal angle between the positron scattering
plane and the rho^0 production plane shows a small but significant violation of
s-channel helicity conservation, corresponding to the production of
longitudinally polarised (i.e. helicity zero) rho^0 mesons from transverse
photons. Measurements of the 15 combinations of spin-density matrix elements
which completely define the angular distributions are presented and discussed.


title:
Study of the structure of e+e- -> b bbar g events and improved limits on
  the anomalous chromomagnetic coupling of the b-quark

abstract:
  The structure of e+e- -> bbg events was studied using Z0 decays recorded in
the SLD experiment at SLAC. Three-jet final states were selected and the
CCD-based vertex detector was used to identify two of the jets as b or bbar.
Distributions of the gluon energy and polar angle were measured over the full
kinematic range, and compared with perturbative QCD predictions. The energy
distribution is potentially sensitive to an anomalous b chromomagnetic moment
kappa. We measured kappa to be consistent with zero and set limits on its
value, -0.11 < kappa < 0.08 at 95% c.l. (preliminary).


title:
Measurement of the probability for gluon splitting into b bbar in Z0
  decays

abstract:
  We present a preliminary measurement of the rate of gluon splitting into
bottom quarks, g -> b bbar, in hadronic Z0 decays collected by SLD between 1996
and 1998. The analysis was performed by looking for secondary bottom production
in 4-jet events of any primary flavour. 4-jet events were identified, and a
topological vertex-mass technique was applied to each jet in order to identify
b or bbar jets. The upgraded CCD based vertex detector gives very high
B-tagging efficiency, especially for B hadrons of the low energies typical of
this process. The two most nearly collinear b/bbar jets were tagged as
originating from g -> b bbar. We measured the rate of secondary b/bbar
production per hadronic event, g_bb, to be (3.07+-0.71(stat.)+-0.66(syst.)) *
10**-3.


title: Measurement of Charge Asymmetries in Charmless Hadronic B Decay

abstract:
  We search for CP violating asymmetries in five charmless hadronic B meson
decays using the full CLEO II and CLEO II.V data samples totalling 9.7 million
BBbar events. The resulting Acp measurements have a precision that varies from
+-0.12 to +-0.25 (absolute) depending on mode. No significant nonzero asymmetry
is observed in any mode but 90% CL limits are strong and rule out some
estimates of Acp.


title:
Structure Functions in the Decay $\tau^{\mp}\to
  \tau^{\mp}\pi^{0}\pi^{0}\nu_{\tau}$

abstract:
  Using the CLEO II detector operating at the CESR e+e- collider, we have
measured the structure functions in the decay tau+/- --> pi+/- pi0 pi0 nu,
based on a sample corresponding to 4*10E6 produced tau-pair events. We
determine the integrated structure functions, which depend only on the three
pion invariant mass, as well as the structure functions differential in the
Dalitz plot. We extract model independent limits on non-axial-vector
contributions from the measured structure functions as less than 16.6% of the
total branching fraction, at the 95% confidence level. Separating the
non-axial-vector contributions into scalar and vector contributions, we measure
that scalars (vectors) contribute with less than 9.4% (7.3%) to the total
branching ratio, at the 95% confidence level.


title: Symmetry Tests in Polarized Z0 Decays to bbg

abstract:
  Angular asymmetries have been measured in polarized Z0 decays to bbg
collected by the SLD experiment at the SLC.
  A high purity bbg event sample is selected by utilizing B lifetime
information given by the SLD CCD pixel vertex detector and the stable
micron-size SLC beams, and the b- and bbar-jets are identified using lifetime
information and momentum-weighted track charge.
  The forward-backward asymmetry is observed in the b-quark polar angle
distribution, and the parity-violation parameter is measured to test the
Standard Model.
  Two angular correlations between the three-jet plane and the Z0 polarization
are studied.
  The CP-even and T-odd, and the CP-odd and T-odd, angular asymmetries are
sensitive to physics beyond the Standard Model. The latter requires tagging
both the b- and bbar-jet. We measure the expectation values of these quantities
to be consistent with zero and set limits on the correlations at the 5% level.


title: Measurement of the b Quark Fragmentation Function in Z0 decay

abstract:
  We present preliminary results of a new measurement of the inclusive b quark
fragmentation function in Z0 decays using a novel kinematic B hadron energy
reconstruction technique. The measurement is performed using 150,000 hadronic
Z0 events recorded in the SLD experiment at SLAC between 1996 and 1997. The
small and stable SLC beam spot and the CCD-based vertex detector are used to
reconstruct topological B-decay vertices with high efficiency and purity, and
to provide precise measurements of the kinematic quantities used in this
technique. We measure the B energy with good efficiency and resolution over the
full kinematic range. We compare the measured scaled B hadron energy
distribution with several functional forms of the B hadron energy distribution
and predictions of several models of b quark fragmentation. Several functions
are excluded by the data. The average scaled energy of the weakly decaying B
hadron is measured to be xB = 0.714 +/- 0.005 (stat) +/- 0.007 (syst) +/- 0.002
(model) (preliminary).


title: Production of Charged pi, K and p in Hadronic Z0 Decays

abstract:
  We have updated our results on identified charged hadron production using the
full SLD data sample of 550,000 hadronic Z^0 decays taken between 1993 and
1998. The SLD Cherenkov Ring Imaging Detector allows the identification of
clean samples of charged pions, kaons and protons over a wide momentum range,
providing precise tests of perturbative QCD calculations and of fragmentation
models. We have studied flavor-inclusive Z^0 decays, as well as decays into
light, c and b flavors, selected using the SLD vertex detector. In addition we
have updated our comparison of hadron and antihadron production in light quark
(rather than antiquark) jets, selected using the high SLC electron beam
polarization. Differences between hadron and antihadron production at high
momentum fraction provide precise measurements of leading particle production
and new, stringent tests of fragmentation models.


title: Study of the Primakoff Reactions at High Energy

abstract:
  In this talk the Coulomb production reactions at high energy are discussed as
well as the study of electromagnetic properties of hadrons (mesons and
hyperons) in these processes. The results of previous investigations are summed
together with some recent data of SELEX(Fermilab) and SPHINX(IHEP) experiments.


title:
A Study of Correlations between Identified Charged Hadrons in Hadronic
  Z^0 Decays

abstract:
  We present a preliminary study of correlations in rapidity between pairs of
identified charged pions, kaons and protons using the entire SLD data sample of
550,000 hadronic Z^0 decays. Short range charge correlations are observed
between all combinations of these hadron species, indicating local conservation
of quantum numbers and charge ordering in the jet fragmentation process. The
rapidity range of this effect is found to be independent of particle momentum.
A strong long-range K^+K^- correlation is observed at high-momentum and weaker
long-range pi^+pi^-, pi^+K^-, pK^- and pp-bar correlations are observed in
light flavor events, providing new information on leading particle production
in u, d and s jets. The long-range correlations observed in c-cbar and bb-bar
events are markedly different and consistent with expectations based on known
decay properties of the leading heavy hadrons. In addition, the SLC electron
beam polarization is used to tag the quark hemisphere in each event, allowing
the first study of rapidities signed such that positive rapidity is along the
quark rather than antiquark direction. Distributions of ordered differences in
signed rapidity between pairs of particles provide a direct probe of quantum
number ordering along the quark-antiquark axis and other new insights into the
fragmentation process.


title: Search for antiproton decay at the Fermilab Antiproton Accumulator

abstract:
  A search for antiproton decay has been made at the Fermilab Antiproton
Accumulator. Limits are placed on thirteen antiproton decay modes. The results
include the first explicit experimental limits on the muonic decay modes of the
antiproton, and the first limits on the decay modes e- gamma gamma, and e-
omega. The most stringent limit is for the decay mode pbar-> e- gamma. At 90%
C.L. we find that tau/B(pbar-> e- gamma) > 7 x 10^5 yr. The most stringent
limit for decay modes with a muon in the final state is for the decay pbar->
mu- gamma. At 90% C.L. we find that tau/B(pbar-> mu- gamma) > 5 x 10^4 yr.


title:
Measurement of $F_2$ and $x F_3$ Structure Functions in Low $Q^2$ Region
  with the IHEP-JINR Neutrino Detector

abstract: This paper has been withdrawn by the authors.


title: A Preliminary Direct Measurement of the s-Quark Coupling

abstract:
  We present an updated direct measurement of the parity-violating coupling of
the Z boson to strange quarks, A_s, derived from the full SLD data sample of
approximately 550,000 hadronic decays of Z bosons produced with a polarized
electron beam and recorded by the SLD experiment at SLAC between 1993 and 1998.
Events with primary strange quarks are tagged by the presence in each event
hemisphere of a high-momentum charged K meson, neutral K meson or Lambda
hyperon identified using the Cherenkov Ring Imaging Detector and/or a mass tag.
The CCD vertex detector is used to suppress the background from heavy flavor
events. The strangeness of the tagged particle is used to sign the event thrust
axis in the direction of the initial strange quark. The coupling A_s is
obtained directly from a measurement of the left-right-forward-backward
production asymmetry in polar angle of the tagged strange quark. The background
from primary up and down events is measured from the data, as is the analyzing
power of the method for primary strange events. We measure: A_s = 0.85 +-
0.06(stat.) +- 0.07(syst.) (preliminary).


title:
Study of charmless hadronic B decays into the final states $K\pi,
  \pi\pi$, and KK, with the first observation of $B \to \pi^+ \pi^-$ and $B\to
  K^0\pi^0$

abstract:
  We have studied charmless hadronic decays of B mesons into two-body final
states with kaons and pions. We present preliminary results based on 9.66
million $B\bar{B}$ pairs collected with the CLEO detector. We have made the
first observation of the decay $B \to \pi^+\pi^-$, with the branching fraction
of $Br(B \to \pi^+ \pi^-) = (4.7^{+1.8}_{-1.5} \pm 0.6) \times 10^{-6}$. We
have also observed for the first time the decay $B \to K^0\pi^0$ with the
branching fraction of $Br(B \to K^0 \pi^0) = (14.8^{+5.9+2.4}_{-5.1-3.3})
\times 10^{-6}$, thus completing the set of four $K\pi$ branching fraction
measurements. We present improved measurements for the decays $B\to
K^{\pm}\pi^{\mp}$, $B^{\pm}\to K^0\pi^{\pm}$, and $B^{\pm}\to K^{\pm}\pi^0$. We
use these and other charmless hadronic B decays to make a first determination
of the value of the weak phase ${\rm Arg}(V^*_{ub})=\gamma =
{113^\circ}^{+25^\circ}_{-23^\circ}$.


title: Search for D0-D0bar Mixing

abstract:
  We report on a search for D0-D0bar mixing made by a study of the `wrong-sign'
process D0 -> K+pi-. The data come from 9.0 fb^-1 of integrated luminosity of
e+e- collisions at sqrt{s} approximately 10 GeV produced by CESR and
accumulated with the CLEO II.V detector. We measure the time-integrated rate of
the `wrong-sign' process D0 -> K+pi-, relative to that of the Cabibbo-favored
D0bar -> K+pi-, to be R_ws=(0.34+-0.07+-0.06)%. By a study of the rate as a
function of the decay time of the D0, we measure the rate of direct, doubly
Cabibbo suppressed decay D0 -> K+pi- relative to D0bar -> K+pi-, to be
R_D=(0.50+0.11-0.12+-0.08)%. The amplitudes that describe D0-D0bar mixing, x'
and y' are consistent with zero. The one-dimensional limits, at the 95% C.L.,
that we determine are (1/2)x^'2<0.05%, and -5.9%<y'<0.3%. All results are
preliminary.


title:
Muon Colliders: New Prospects for Precision Physics and the High Energy
  Frontier

abstract:
  An overview is given of muon collider technology and of the current status of
the muon collider research program. The exciting potential of muon colliders
for both neutrino physics and collider physics studies is then described and
illustrated using self-consistent collider parameter sets at 0.1 TeV to 100 TeV
center-of-mass energies.


title: Muon Colliders: the Ultimate Neutrino Beamlines

abstract:
  It is shown that muon decays in straight sections of muon collider rings will
naturally produce highly collimated neutrino beams that can be several orders
of magnitude stronger than the beams at existing accelerators. We discuss
possible experimental setups and give a very brief overview of the physics
potential from such beamlines. Formulae are given for the neutrino event rates
at both short and long baseline neutrino experiments in these beams.


title: Search for neutrino oscillations with KARMEN

abstract:
  Results from the search for muon anti neutrino to electron anti neutrino
oscillations with the karmen experiment. Results are based on the data taken
from Feb.97 to Feb.99.


title:
Application of Bayesian probability theory to the measurement of
  binomial data at past and future Tevatron experiments

abstract:
  The experimental problem of converting a measured binomial quantity, the
fraction of events in a sample that pass a cut, into a physical binomial
quantity, the fraction of events originating from a signal source, is described
as a system of linear equations. This linear system illustrates several
familiar aspects of experimental data analysis. Bayesian probability theory is
used to find a solution to this binomial measurement problem that allows for
the straightforward construction of confidence intervals. This solution is also
shown to provide an unbiased formalism for evaluating the behavior of data sets
under different choices of cuts, including a cut designed to increase the
significance of a possible, albeit previously unseen, signal.
  Several examples are used to illustrate the features of this method,
including the discovery of the top quark and searches for new particles
produced in association with $W^{\pm}$ bosons. It is also demonstrated how to
use this method to make projections for the potential discovery of a Standard
Model Higgs boson at a Tevatron Run 2 experiment, as well as the utility of
measuring the integrated luminosity through inclusive $p\bar{p} \to W^{\pm}$
production.


title: Partial Wave Analysis of $J/\psi \to \gamma (K^+K^-\pi^+\pi^-)$

abstract:
  BES data on $J/\psi \to \gamma (K^+K^-\pi^+\pi^-)$ are presented. The
$K^*\bar K^*$ contribution peaks strongly near threshold. It is fitted with a
broad $0^{-+}$ resonance with mass $M = 1800 \pm 100$ MeV, width $\Gamma = 500
\pm 200$ MeV. A broad $2^{++}$ resonance peaking at 2020 MeV is also required
with width $\sim 500$ MeV. There is further evidence for a $2^{-+}$ component
peaking at 2.55 GeV. The non-$K^*\bar K^*$ contribution is close to phase
space; it peaks at 2.6 GeV and is very different from $K^{*}\bar{K^{*}}$.


title:
Measurement of the Total Cross Section for Hadronic Production by e+e-
  Annihilation at Energies between 2.6-5 Gev

abstract:
  Using the upgraded Beijing Spectrometer (BESII), we have measured the total
cross section for $e^+e^-$ annihilation into hadronic final states at
center-of-mass energies of 2.6, 3.2, 3.4, 3.55, 4.6 and 5.0 GeV. Values of $R$,
$\sigma(e^+e^-\to {hadrons})/\sigma(e^+e^-\to\mu^+\mu^-)$, are determined.


title: Neutrino Oscillations at Reactors: What Next?

abstract:
  We shortly review past and future experiments at reactors aimed at searches
for neutrino masses and mixing. We also consider new idea to search at
Krasnoyarsk for small mixing angle oscillations in the atmosheric neutrino mass
parameter region.


title:
The Search of Large Cross Section Asymmetries in the Pair Production
  Process by Polarized Photons

abstract:
  The regions of pair particle energies and emergence angles in the process of
photoproduction of electron-positron pairs in the coulomb field by polarized
photons are found in which a value of cross section asymmetry is essentially
large. The distributions of pair particles on energy and on angles are
calculated by the Monte-Carlo method. The obtained results for pair particle
yield and asymmetry permit us to conclude that on their basis can be developed
a new effective method for polarized photon polarimetry.


title: Neutrino-induced upward stopping muons in Super-Kamiokande

abstract:
  A total of 137 upward stopping muons of minimum energy 1.6 GeV are observed
by Super-Kamiokande during 516 detector live days. The measured muon flux is
0.39+/-0.04(stat.)+/-0.02(syst.)x10^{-13}cm^{-2}s^{-1}sr^{-1} compared to an
expected flux of 0.73+/-0.16(theo.)x10^{-13}cm^{-2}s^{-1}sr^{-1}. Using our
previously-published measurement of the upward through-going muon flux, we
calculate the stopping/through-going flux ratio R}, which has less theoretical
uncertainty. The measured value of R=0.22+/-0.02(stat.)+/-0.01(syst.) is
significantly smaller than the value 0.37^{+0.05}_{-0.04}(theo.) expected using
the best theoretical information (the probability that the measured R is a
statistical fluctuation below the expected value is 0.39%). A simultaneous
fitting to zenith angle distributions of upward stopping and through-going
muons gives a result which is consistent with the hypothesis of neutrino
oscillations with the parameters sin^2 2\theta >0.7 and 1.5x10^{-3} < \Delta
m^2 < 1.5x10^{-2} eV^2 at 90% confidence level, providing a confirmation of the
observation of neutrino oscillations by Super-Kamiokande using the contained
atmospheric neutrino events.


title:
How Could CP-Invariance and Physics Beyond SM Be Tested in Polarized
  Proton Collisions at RHIC?

abstract:
  Just in months ahead, the first high luminosity collisions of two polarized
proton beams are expected to occur at RHIC in BNL at sqrt{s} up to 500 GeV,
bringing a new quality to the collider physics. In collisions of polarized
particles, the presence of two axial vectors of initial polarizations, fully
controlled by experimenters, may dramatically increase the number of available
for tests correlations between participating vectors, generating asymmetries
that could relatively easily be measured. In frame of Standard Model (SM), many
of these asymmetries are either strongly suppressed or strictly prohibited.
Therefore, if some of them were found nonzero, this could be an indication of a
new physics beyond SM. If certain criteria met, it might be difficult to
explain the observed nonzero correlations in theories without CP- and/or
T-violation.


title: The Physics Case for Polarized Protons at HERA

abstract:
  Several important and unique measurements, within the standard model and of
possible physics beyond it, could be made with {\em polarized HERA} in which
both the proton and the electron beams are polarized. With a $\sim$820 GeV
proton beam and a $\sim$27.6 GeV electron beam, the polarized HERA will enable
$\vec{e}-\vec{p}$ collisions with $\sqrt{s} \sim 300$ GeV and access spin
variables in the kinematic range, $10^{-5} \le x_{\rm Bj} \le 0.6$ and $0 \le
Q^{2} \le 10^{5}$, using the H1 and ZEUS detectors at DESY. This will be an
increase of two orders of magnitude in both $x$ and $Q^{2}$ range compared to
the presently explored range from fixed target experiments at CERN, SLAC and
DESY. No other approved or planned spin experiment or accelerator facility will
access the low $x$ and high $Q^{2}$ regions possible with HERA. Measurements
performed with the polarized HERA collider will include the polarized structure
function $g_{1}(x,Q^{2})$ at very low $x$, the polarized gluon distribution
$\Delta G(x,Q^{2})$ from pQCD analysis of $g_{1}$, and from the production of
di-jet events and high-p$_{T}$ hadrons in photon gluon fusion process and in
photoproduction, the weak structure functions, the valence quark distribution
functions from semi-inclusive asymmetries, parton distributions inside
polarized photon, and information on helicity structure of possible new physics
beyond the standard model. With such a rich and broad physics program possible
for HERA,not polarizing the proton beam would be a great opportunity lost.


title:
The Tevatron Tripler: How to Upgrade the Fermilab Tevatron for the Higgs
  Boson and Supersymmetry

abstract:
  Recent advances in superconductor properties and superconducting magnet
technology have made it possible to build cost-effective, high-performance
dipoles with a field of 12 Tesla - 3 times the field strength of the Tevatron.
Such magnets could be used to upgrade Fermilab's collider in its existing
tunnel to a collision energy $\sqrt s$= 6 TeV and luminosity {$\cal L$}$>$
10$^{33}$ cm$^{-2}$s$^{-1}$. We have calculated the parton luminosities for
quark-antiquark and gluon-gluon scattering for the Tevatron, the Tripler, and
LHC. In most models of the Higgs field and supersymmetry, the Tripler would
have a high likelihood to discover many of the predicted particle states.


title: Disclosure of New Stable Heavy Charged Particles in Cosmic Rays

abstract:
  A telescope of two coaxial scintillation detectors (an upper thin CsJ crystal
of d63x0,35mm2 and a lower thick NaJ crystal of d150x100 mm2) located
vertically on the surface of the Earth was used to have during T=106 hours 20
events registered with increased specific ionization in each detector that
turned out to exceed 10 times the specific ionization caused by cosmic rays.
All the events excluding three background events are within two standard
deviations from a curve calculated for non-relativistic single charged
particles with mass M=(175 +/- 25)GeV/C2, flying vertically along the
telescope. Based upon the condition of being non-relativistic and the
limitations on the dimentions of the experimental set-up, it follows that their
life-time t >1,5*10-9s. Their intensity in cosmic rays on the Earth surface is
J=(1,8 +/- 0,4)*10-6cm-2 ster-1 s-1 (at E<6 GeV, P<50 GeV/C). The events
disclosed are in full correspondence with our phenomenological predictions,
with previous experimental results in the course of searching them for, and
with the predictions of the "mirror model" which interpreters a possibility of
existing hypothetical stable heavy hadrons (Erzions).


title: Recent Charm Results from Fermilab Experiment E791

abstract:
  Fermilab experiment E791 studied weak decays of D+, D_s, and D^0 mesons
produced in collisions of 500 GeV/c negative pions with Pt and C targets. The
experiment collected over 200,000 fully reconstructed charm decays. Four recent
results are discussed here: (a) measurement of the form factor ratios V/A_1,
A_2/A_1, and A_3/A_1 in D->K*-l-nu and Ds->phi-l-nu decays; (b) measurement of
the difference in decay widths $\Delta\Gamma$ between the two D^0/D^0-bar mass
eigenstates; (c) search for rare and forbidden D decays to dilepton final
states; and (d) search for a ``Pentaquark,'' a bound state of c-bar-suud.


title:
Measurement of the CP-violation parameter sin(2beta) in B0 to
  J/psi-Kshort decays

abstract:
  A sample of 400 $B^0_d/\bar{B}{^0_d} \to J/\psi K^0_s$ decays collected in
$\bar{p}p$ collisions by the CDF detector is used to directly measure the
CP-violation parameter $\sin(2\beta)$. We find $\sin(2\beta) = 0.79
^{+0.41}_{-0.44}$,favoring the standard model expectation of a large $CP$
violation in this $B^0$ decay mode.


title: Precision Calibration of the NuTeV Calorimeter

abstract:
  NuTeV is a neutrino-nucleon deep-inelastic scattering experiment at Fermilab.
The detector consists of an iron-scintillator sampling calorimeter interspersed
with drift chambers, followed by a muon toroidal spectrometer. We present
determinations of response and resolution functions of the NuTeV calorimeter
for electrons, hadrons, and muons over an energy range of 4.8 to 190 GeV. The
absolute hadronic energy scale is determined to an accuracy of 0.43%. We
compare our measurements to predictions from calorimeter theory and GEANT3
simulations.


title: A measurement of the W boson mass using large rapidity electrons

abstract:
  We present a measurement of the W boson mass using data collected by the D0
experiment at the Fermilab Tevatron during 1994--1995. We identify W bosons by
their decays to e-nu final states where the electron is detected in a forward
calorimeter. We extract the W boson mass, Mw, by fitting the transverse mass
and transverse electron and neutrino momentum spectra from a sample of 11,089 W
-> e nu decay candidates. We use a sample of 1,687 dielectron events, mostly
due to Z -> ee decays, to constrain our model of the detector response. Using
the forward calorimeter data, we measure Mw = 80.691 +- 0.227 GeV. Combining
the forward calorimeter measurements with our previously published central
calorimeter results, we obtain Mw = 80.482 +- 0.091 GeV.


title:
Studies of Higher Twist and Higher Order Effects in NLO and NNLO QCD
  Analysis of Lepton-Nucleon Scattering Data on F_2 and R =sigma_L/sigma_T

abstract:
  We report on the extraction of the higher twist contributions to F_2 and R =
sigma_L/sigma_T from the global NLO and NNLO QCD fits to lepton nucleon
scattering data over a wide range of Q^2. The NLO fits require both target mass
and higher twist contributions at low Q^2. However, in the NNLO analysis, the
data are described by the NNLO QCD predictions (with target mass corrections)
without the need for any significant contributions from higher twist effects.
An estimate of the difference between NLO and NNLO parton distribution
functions is obtained.


title:
Measurement of Neutral and Charged Current Cross-Sections in
  Positron-Proton Collisions at Large Momentum Transfer

abstract:
  The inclusive single and double differential cross-sections for neutral and
charged current processes with four-momentum transfer squared Q^2 between 150
and 30,000 GeV2 and with Bjorken x between 0.0032 and 0.65 are measured in e^+
p collisions. The data were taken with the H1 detector at HERA between 1994 and
1997, and they correspond to an integrated luminosity of 35.6 pb^-1. The Q^2
evolution of the parton densities of the proton is tested, yielding no
significant deviation from the prediction of perturbative QCD. The proton
structure function F_2(x,Q^2) is determined. An extraction of the u and d quark
distributions at high x is presented. At high Q^2 electroweak effects of the
heavy bosons Z0 and W are observed and found to be consistent with Standard
Model expectation.


title: Results from the ARGO-YBJ Test Experiment

abstract:
  An RPC carpet covering ~10**4 m**2 (ARGO-YBJ experiment) will be installed in
the YangBaJing Laboratory (Tibet, P.R. China) at an altitude of 4300 m a.s.l..
A test-module of ~50 m**2 has been put in operation in this laboratory and
about 10**6 air shower events have been collected. The carpet capability of
reconstructing the shower features is presented.


title:
Determination of the total ccbar production cross section in 340 GeV/c
  Sigma- - nucleus interactions

abstract:
  The production of charmed particles by Sigma- of 340 Gev/c momentum was
studied in the hyperon beam experiment WA89 at the CERN-SPS, using the
Omega-spectrometer. In two data-taking periods in 1993 and 1994 an integrated
luminosity of 1600 microb^-1 on copper and carbon targets was recorded. From
the reconstruction of 930 +- 90 charm particle decays in 10 decay channels
production cross sections for D, antiD, Ds and Lambdac were determined in the
region xF>0. Assuming an A^1 dependence of the cross section on the nucleon
number, we calculate a total ccbar production cross section of sigma(x_F > 0) =
5.3+- 0.4(stat)+-1.0(syst)+1.0(Xi_c) microb per nucleon. The last term is an
upper limit on the unknown contribution from charmed-strange baryon production.


title: CP Violation in B Decays at the Tevatron

abstract:
  Between 1992 to 1996, the CDF and D0 detectors each collected data samples
exceeding 100 pb^{-1} of p\bar{p} collisions at sqrt{s}=1.8 TeV at the Fermilab
Tevatron. These data sets led to a large number of precision measurements of
the properties of B hadrons including lifetimes, masses, neutral B meson flavor
oscillations, and relative branching fractions, and to the discovery of the B_c
meson. Perhaps the most exciting result was the first look at the CP violation
parameter sin(2beta) using the world's largest sample of fully reconstructed
B^0/bar{B}^0 -> J/psi K^0_S decays. A summary of this result is presented here.
In the year 2000, the Tevatron will recommence p\bar{p} collisions with an over
order of magnitude expected increase in integrated luminosity (1 fb^{-1} per
year). The CDF and D0 detectors will have undergone substantial upgrades,
particularly in the tracking detectors and the triggers. With these
enhancements, the Tevatron B physics program will include precision
measurements of sin(2beta) and B^0_s flavor oscillations, as well as studies of
rare B decays that are sensitive to new physics. The studies of B^0_s mesons
will be particularly interesting as this physics will be unique to the Tevatron
during the first half of the next decade.


title:
Search for R-parity Violating Supersymmetry using Like-Sign Dielectrons
  in \ppbar Collisions at $\sqrt{s} = 1.8$ TeV

abstract:
  We present a search for like-sign dielectron plus multijet events using 107
pb-1 of data in \ppbar collisions at $\sqrt{s} = 1.8$ TeV collected in 1992-95
by the CDF experiment. Finding no events that pass our selection, we set
$\sigma\cdot Br$ limits on two SUSY processes that can produce this
experimental signature: gluino-gluino or squark-antisquark production with
R-parity violating decays of the charm squark or lightest neutralino via a
non-zero lambda'_121 coupling. We compare our results to NLO calculations for
gluino and squark production cross sections and set lower limits on M(gluino),
M(stop1), and M(squark).


title: Low Q^2 low x structure function analysis of CCFR data for F2

abstract:
  Analyses of structure functions (SFs) from neutrino and muon deep inelastic
scattering data have shown discrepancies in F2 for x < 0.1. A new SF analysis
of the CCFR collaboration data examining regions in x down to x=.0015 and 0.4 <
Q^2 < 1.0 is presented. Comparison to corrected charged lepton scattering
results for F2 from the NMC and E665 experiments are made. Differences between
muon and neutrino scattering allow that the behavior of F2 from muon scattering
could be different from F2 from neutrino scattering as Q^2 approaches zero.
Comparisons between F2 muon and F2 neutrino are made in this limit.


title: Measurement of the Higgs Cross Section and Mass with Linear Colliders

abstract:
  We report on the accuracy of the measurement of the Higgs boson mass and the
total cross section of the process e+e- -> ZH that would be achieved in a
linear collider operating at a centre-of-mass energy of 350 GeV, assuming an
integrated luminosity of 500 (1/fb). For that we have exploited the recoil mass
off the Z using its leptonic decays into electron and muon pairs. The Higgs
mass is determined with 150 MeV accuracy, the recoil mass resolution is about
1.5 GeV and the cross section is obtained with a statistical error of 3%.


title: Atmospheric Neutrino Physics with the MACRO detector

abstract:
  We present the measurement of the the flux and angular distribution of
atmospheric muon neutrinos using the MACRO detector. Three different event
topologies are detected in two different energy ranges. High energy neutrinos
(E~80 GeV) via the identification of upward throughgoing muons. Lower energy
neutrinos (E~ 4 GeV) via the upgoing stopping and partially contained downgoing
muons (ID+UGS), or via the partially contained upgoing muons (IU). The measured
flux is reduced with respect to the predictions. For the high energy sample,
globally the flux reduction is $0.74\pm 0.054_{stat+sys} \pm 0.12_{th}$ and
varies with the zenith angle. The ratio of measured to expected events is
almost constant with the zenith angle for the low energy events, and is $0.57
\pm 0.08_{stat+sys} \pm 0.14_{theor}$ for the IU sample, and $0.71 \pm
0.09_{stat+sys} \pm 0.17_{theor}$ for the (ID+UGS). All the data sets are
consistent within a scenario of neutrino oscillations, with maximum mixing and
$\Delta m^2 \sim 10^{-3}\div 10^{-2} eV^2$.


title: QCD Tests at HERA

abstract:
  Measurements of inclusive jet, dijet and three-jet cross sections in
photon-proton interactions are presented. These measurements provide new tests
of QCD, constrain the parton densities of the photon, and allow searches for
new physics. Measurements of the mean subjet multiplicity are reported and used
to test the differences between quark and gluon jets.


title:
Study of QED processes e+ e- --> e+ e- gamma, e+ e- gamma gamma with the
  SND detector at VEPP-2M

abstract:
  Results of the SND experiment at the VEPP-2M e+ e- collider on the QED
processes e+ e- --> e+ e- gamma and e+ e- --> e+ e- gamma gamma with production
at large angles are presented. Energy and angular distributions of the final
particles were studied. No deviations from QED with an accuracy of 3.8% for the
first process and 10.3% for the second were found.


title: Two Photon Physics at LEP

abstract:
  LEP offers an excellent opportunity to measure two photon processes over a
large kinematical range and thus study the complex nature of the photon. This
article reviews the experimental status of ``Two Photon Physics'' at LEP. The
recent results on resonances, multi-hadron production and photon structure
functions are discussed


title: Searches for Other Higgs Bosons at LEP

abstract:
  Recent LEP searches for Higgs bosons in models other than the Minimal
Standard Model and the Minimal Supersymetric Standard Model are reviewed.
Limits are presented for Higgs bosons decaying into diphotons or invisible
particles, and for charged Higgs bosons.


title:
A Measurement of $\sin 2\beta$ from $B\to J/\psi K^0_S$ with the CDF
  detector

abstract:
  This paper reports an updated measurement of the Standard Model CP violation
parameter $\sin2\beta$ using the CDF Detector at Fermilab. The entire Run I
data sample of 110 pb$^{-1}$ of proton antiproton collisions at $\sqrt{s}=1.8
TeV$ is used to identify a signal sample of $\sim 400$ $B \to J/\psi K^0_S$
events, where $J/\psi \to \mu^+\mu^-$ and $K_S^0 \to \pi^+\pi^-$. The flavor of
the neutral B meson is identified at the time of production by combining
information from three tagging algorithms: a same-side tag, a jet-charge tag,
and a soft-lepton tag. A maximum likelihood fitting method is used to determine
$\sin2\beta = 0.79 {+0.41\atop-0.44}$(stat+syst). This value of $\sin 2 \beta$
is consistent with the Standard Model prediction, based upon existing
measurements, of a large positive CP violating asymmetry in this decay mode.


title:
Search for the Standard Model Higgs boson in e$^+$e$^-$ interactions at
  $\root{s}$ = 189 GeV

abstract:
  A search for the Standard Model Higgs boson is carried out on 176.4pb$^{-1}$
of data collected by the L3 detector at a center-of-mass energy of 189 GeV. The
data are consistent with the expectations of Standard Model processes and no
evidence of a Higgs signal is observed. Combining the results of this search
with those at lower center-of-mass energies, a lower limit on the mass of the
Standard Model Higgs boson of 95.3 GeV is set at the 95% confidence level.


title:
Measurement of Inclusive $D^{*\pm}$ Production in Two-Photon Collisions
  at LEP

abstract:
  Inclusive production of $\mathrm{D^{*\pm}}$ mesons in two-photon collisions
was measured by the L3 experiment at LEP. The data were collected at a
centre-of-mass energy $\sqrt{s} = 189$ GeV with an integrated luminosity of
$176.4 \mathrm{pb^{-1}}$. Differential cross sections of the process
$\mathrm{e^+e^- \to D^{*\pm} X}$ are determined as functions of the transverse
momentum and pseudorapidity of the $\mathrm{D^{*\pm}}$ mesons in the kinematic
region 1 GeV $< p_{T}^{\mathrm{D^*}} < 5 $ GeV and $\mathrm{|\eta^{D^*}|} <
1.4$. The cross section integrated over this phase space domain is measured to
be $132 \pm 22(stat.) \pm 26(syst.)$ pb. The differential cross sections are
compared with next-to-leading order perturbative QCD calculations.


title:
Search for Heavy Isosinglet Neutrinos in e$^+$e$^-$ Annihilation at
  130$<\sqrt{s}<$189 GeV

abstract:
  A search for heavy neutrinos that are isosinglets under the standard
$SU(2)_L$ gauge group is made at center-of-mass energies 130 $< \sqrt{s} <$ 189
GeV with the L3 detector at LEP. Such heavy neutrinos are expected in many
extensions of the Standard Model. The search is performed for the first
generation heavy singlet neutrino, $\mathrm{N}_e$, through the decay mode
$\mathrm{N}_e \to \mathrm{e} + \mathrm{W}$. We set upper limits on the mixing
parameter between the heavy and light neutrino for the heavy neutrino mass
range from 80 GeV to 185 GeV.


title:
Search for Heavy Neutral and Charged Leptons in e$^+$e$^-$ Annihilation
  at $\sqrt{s}$ = 183 and 189 GeV

abstract:
  A search for unstable neutral and charged heavy leptons as well as for stable
charged heavy leptons is performed at center-of-mass energies $\sqrt{s}$ = 183
and 189 GeV with the L3 detector at LEP. No evidence for their existence is
found. We exclude neutral heavy leptons which couple to the electron, muon or
tau family, of the Dirac type for masses below 92.4, 93.3 and 83.3 GeV, and of
the Majorana type for masses below 81.8, 84.1 and 73.5 GeV, respectively. We
exclude unstable charged heavy leptons for masses below 93.9 GeV for a wide
range of the associated neutral heavy lepton mass. If the unstable charged
heavy lepton decays to a light neutrino, we exclude masses below 92.4 GeV. The
production of stable charged heavy leptons with mass less than 93.5 GeV is also
excluded.


title: Formation of the $\eta_c$ in Two-Photon Collisions at LEP

abstract:
  The two-photon width $\Gamma_{\gamma\gamma}$ of the $\eta_c$ meson has been
measured with the L3 detector at LEP. The $\eta_c$ is studied in the decay
modes $\pi^+\pi^-\pi^+\pi^-$, $\pi^+\pi^-$K$^+$K$^-$, K$_s^0$K$^\pm\pi^\mp$,
K$^+$K$^-\pi^{0}$, $\pi^+\pi^-\eta$, $\pi^+\pi^-\eta'$, and $\rho^+\rho^-$
using an integrated luminosity of 140 pb$^{-1}$ at $\sqrt{s} \simeq 91$ GeV and
of 52 pb$^{-1}$ at $\sqrt{s} \simeq 183$ GeV. The result is
$\Gamma_{\gamma\gamma}(\eta_c) = 6.9 \pm 1.7 (stat.) \pm 0.8 (sys.) \pm
2.0$(BR) keV. The $Q^2$ dependence of the $\eta_c$ cross section is studied for
$Q^2 < 9$ GeV$^{2}$. It is found to be better described by a Vector Meson
Dominance model form factor with a J-pole than with a $\rho$-pole. In addition,
a signal of $29 \pm 11$ events is observed at the $\chi_c0$ mass. Upper limits
for the two-photon widths of the $\chi_c0$, $\chi_c2$, and $\eta_c'$ are also
given.


title: Measurement of an Elongation of the Pion Source in Z Decays

abstract:
  We measure Bose-Einstein correlations between like-sign charged pion pairs in
hadronic Z decays with the L3 detector at LEP. The analysis is performed in
three dimensions in the longitudinal center-of-mass system. The pion source is
found to be elongated along the thrust axis with a ratio of transverse to
longitudinal radius of $0.81\pm 0.02 ^{+0.03}_{-0.19}$.


title: Measurement of Mass and Width of the W Boson at LEP

abstract:
  We report on measurements of the mass and total decay width of the W boson
with the L3 detector at LEP. W-pair events produced in $\mathrm{e^+e^-}$
interactions between 161 GeV and 183 GeV centre-of-mass energy are selected in
a data sample corresponding to a total luminosity of 76.7 pb$^{-1}$. Combining
all final states in W-pair production, the mass and total decay width of the W
boson are determined to be $\mathrm{M_W}=80.61\pm0.15$ GeV and
$\Gamma_{\mathrm{W}}=1.97\pm0.38$ GeV, respectively.


title:
Measurement of b Quark Fragmentation Fractions in p-pbar Collisions at
  sqrt(s)=1.8 TeV

abstract:
  We have studied the production of B hadrons in 1.8-TeV p-pbar collisions. We
present measurements of the fragmentation fractions, f_u, f_d, f_s and
f_baryon, of produced b quarks that yield B^+, B^0, B^0_s and Lambda_b hadrons.
Reconstruction of several electron-charm final states yields
f_s/(f_u+f_d)=0.213+/-0.068 and f_baryon/(f_u+f_d)=0.118+/-0.042, assuming
f_u=f_d. If all B hadrons produced in p-pbar collisions cascade to one of these
four hadrons, we determine f_u=f_d=0.375+/-0.023, f_s=0.160+/-0.044 and
f_baryon=0.090+/-0.029. If we do not assume f_u=f_d, we find
f_d/f_u=0.84+/-0.16.


title: Search for magnetic monopoles with nuclear track detectors

abstract:
  This paper describes an experimental search for GUT magnetic monopoles in the
MACRO experiment using the nuclear track subdetector CR39. After discussing the
working principle, the charge resolution and the calibration of the detector,
the experimental procedure for searching for magnetic monopoles is described.
Since no candidates were found, the upper flux limits obtained by the MACRO
CR39 used as a "stand alone detector" for magnetic monopoles of different
magnetic charges are presented.


title: Experimental evidence for a vector-like behaviour of Pomeron exchange

abstract:
  Evidence is presented that the Pomeron act as a non-conserved vector current.
A study has been made of the azimuthal angle phi, which is defined as the angle
between the pT vectors of the two outgoing protons, in the reaction pp ->
pp(X0) for those resonances (X0) which are compatible with being produced by
double Pomeron exchange. These distributions have been compared with a model
which describes the Pomeron as a non-conserved vector current and a qualitative
agreement is found. In addition, when one of the particles exchanged is known
to have spin 0, namely pi-Pomeron exchange, the phi distribution is flat.


title: CDF B spectroscopy results: B^** and B_c

abstract:
  We report on two spectroscopy results from CDF. First, we observe the
orbitally excited $B^{**}$ mesons in $B \to \ell D^{(*)}X$ events. We find $28
\pm 6 \pm 3$% of light $B$ mesons produced are $B^{**}$ states. A collective
mass fit results in a $B_1$ mass of $5.71 \pm 0.02$ GeV/$c^2$. Secondly, we
observe $20.4^{+6.2}_{-5.5}$ decays of $B^+_c \to J/\psi \ell^+X$, with a $
6.40 \pm 0.39 \pm 0.13 {\rm GeV}/c^2$ mass and $ 0.46 ^{+0.18}_{-0.16} \pm 0.03
$ps lifetime. The production rate is in reasonable accordance with
expectations.


title: Spherical Neutral Detector for VEPP-2M collider

abstract:
  The Spherical Neutral Detector (SND) operates at VEPP-2M collider in
Novosibirsk studying e^+e^- annihilation in the energy range up to 1.4 GeV.
Detector consists of a fine granulated spherical scintillation calorimeter with
1632 NaI(Tl) crystals, two cylindrical drift chambers with 10 layers of sense
wires, and a muon system made of streamer tubes and plastic scintillation
counters. The detector design, performance, data acquisition and processing are
described.


title: Single Top Production and Top Properties at the Tevatron

abstract:
  We summarize recent measurements made at the Tevatron Collider using top
event candidates. Cross section and mass measurements are discussed in a
separate contribution to these Proceedings. Here we report on studies of the
top P$_T$ distribution in $\ttbar$ production and studies of single top
production. Properties of top decays examined are:
  BF($t \into Wb$)/BF($t \into Wq$), helicity amplitudes of W's from top decays
and correlations of $\ttbar$ decay products. Searches for new physics in rare
top decays and a search for a state X $\into \ttbar$ are also reported.


title: Supersensitive avalanche silicon drift photodetector

abstract:
  Physical principles of performance and main characteristics of a novel
avalanche photodetector developed on the basis of MOS(metal-oxide-silicon)
technology is presented. The photodetector contains a semitransparent gate
electrode and a drain contact to provide a drift of multiplicated charge
carriers along the semiconductor surface. A high gain(more than 10^4) of
photocurrent was achived due to the local negative feedback effect realizied on
the Si-SiO_2 boundary. Special attention is paid to the possibilities of
development of a supersensitive avalanche CCD (charge coupled device) for
detection of individual photons in visible and ultraviolet spectral regions.
Experimental results obtained with a two-element CCD prototype are discussed.


title: Measurement of the Spectroscopy of Orbitally Excited B Mesons at LEP

abstract:
  We measure the masses, decay widths and relative production rate of orbitally
excited B mesons using 1.25 million hadronic Z decays recorded by the L3
detector. B-meson candidates are inclusively reconstructed and combined with
charged pions produced at the primary event vertex. An excess of events above
the expected background in the B\pi mass spectrum in the region 5.6-5.8 GeV is
interpreted as resulting from the decay B_u,d^** -> B^(*)\pi, where B_u,d^**
denotes a mixture of l=1 B-meson states containing a u or a d quark. A fit to
the mass spectrum yields the masses and decay widths of the B_1^* and B_2^*
spin states, as well as the branching fraction for the combination of l=1
states. In addition, evidence is presented for the existence of an excited
B-meson state or mixture of states in the region 5.9-6.0 GeV.


title: Search for Low Scale Gravity Effects in e+e- Collisions at LEP

abstract:
  Recent theories propose that quantum gravity effects may be observable at LEP
energies via gravitons that couple to Standard Model particles and propagate
into extra spatial dimensions. The associated production of a graviton and a
photon is searched for as well as the effects of virtual graviton exchange in
the processes: e+e- -> gamma gamma, ZZ, WW, mu mu, tau tau, qq and ee No
evidence for this new interaction is found in the data sample collected by the
L3 detector at LEP at centre-of-mass energies up to 183 GeV. Limits close to 1
TeV on the scale of this new scenario of quantum gravity are set.


title:
Differential Production Cross Section of Z Bosons as a Function of
  Transverse Momentum at sqrt{s}=1.8 TeV

abstract:
  We present a measurement of the transverse momentum distribution of Z bosons
produced in ppbar collisions at sqrt{s}=1.8 TeV using data collected by the D0
experiment at the Fermilab Tevatron Collider during 1994--1996. We find good
agreement between our data and a current resummation calculation. We also use
our data to extract values of the non-perturbative parameters for a particular
version of the resummation formalism, obtaining significantly more precise
values than previous determinations.


title: GPS Time Synchronization System for K2K

abstract:
  The K2K (KEK E362) long-baseline neutrino oscillations experiment requires
synchronization of clocks with ~100 nsec accuracy at the near and far detector
sites (KEK and Super-Kamiokande, respectively), which are separated by 250 km.
The Global Positioning System (GPS) provides a means for satisfying this
requirement at very low cost. In addition to low-resolution time data (day of
year, hour, minute, second), commercial GPS receivers output a 1 pulse per sec
(1PPS) signal whose leading edge is synchronized with GPS seconds rollovers to
well within the required accuracy. For each beam spill trigger at KEK, and each
event trigger at Super-Kamiokande, 50 MHz free-running Local Time Clock (LTC)
modules at each site provide fractional-second data with 20 nsec ticks. At each
site, two GPS clocks run in parallel, providing hardware backup as well as data
quality checks.


title:
A new measurement of direct CP violation in two pion decays of the
  neutral kaon

abstract:
  The NA48 experiment at CERN has performed a new measurement of direct CP
violation, based on data taken in 1997 by simultaneously collecting K_L and K_S
decays into pi0pi0 and pi+pi-. The result for the CP violating parameter
Re(epsilon'/epsilon) is (18.5 +/- 4.5(stat)} +/- 5.8 (syst))x10^{-4}.


title: Experimental Results on Two-Photon Physics from LEP

abstract:
  This review covers selected results from the LEP experiments on the structure
of quasi-real and virtual photons.
  The topics discussed are the total hadronic cross-section for photon-photon
scattering, hadron production, jet cross-sections, heavy quark production for
photon-photon scattering, photon structure functions, and cross-sections for
the exchange of two virtual photons.


title: Tests of QCD using differences between gluon and quark jets

abstract:
  I present recent results from LEP which utilize differences between gluon and
quark jets to make quantitative tests of QCD. The principal topic is a
determination of the ratio of QCD color factors,
C$_{\mathrm{A}}$/C$_{\mathrm{F}}$, using either the multiplicity or
fragmentation functions of the jets. In addition, I discuss a recent
measurement of the rate of $\eta$ mesons in gluon jets compared to quark jets.


title: Space charge in ionization detectors and the NA48 calorimeter

abstract:
  The effects of space charge due to slowly drifting ions can be relevant for
detectors operated at high intensity, or for relatively low values of the bias
voltage. Accurate measurements have been obtained with the liquid krypton
calorimeter of the NA48 experiment, from data collected in 1997. The build-up
of space charge takes place during the first part of the beam extraction burst,
and causes a dependence of the response on the transverse coordinate of the
axis of electromagnetic showers, and a small reduction of average amplitude.
The effects are well reproduced by a computation, where the only free parameter
is the value of the ion mobility. The model can be applied a wide range of
operating conditions, and generalized to detectors with different geometry and
active medium.


title: Short-Range and Long-Range Correlations in DIS at HERA

abstract:
  Correlations in deep-inelastic scattering at HERA are investigated in order
to test perturbative QCD and quark fragmentation universality. Two-particle
correlations at small angular separations are measured in the Breit frame and
compared to e+e- collisions. Also presented are the correlations between the
current and target regions of the Breit frame.


title:
Search for a Fourth-Generation Quark More Massive than the Z0 Boson in
  ppbar Collisions at sqrt(s) = 1.8 TeV

abstract:
  We present the results of a search for pair production of a fourth-generation
charge -1/3 quark (b') in sqrt(s)=1.8 TeV ppbar collisions using 88 pb^(-1) of
data obtained with the Collider Detector at Fermilab. We assume that both
quarks decay via the flavor-changing neutral current process b' -> bZ and that
the b' mass is greater than m_Z + m_b. We studied the decay mode b'b'bar -> ZZ
b bbar where one Z0 decays into e^+e^- or mu^+ mu^- and the other decays
hadronically, giving a signature of two leptons plus jets. An upper limit on
the cross section of ppbar -> b'b'bar times [BR (b' -> bZ)]^2 is established as
a function of the b' mass. We exclude at 95% confidence level a b' quark with
mass between 100 and 199 GeV/c^2 for BR(b' -> bZ) = 100%.


title: Search for D0-D0bar Mixing

abstract:
  We report on a search for D0-D0bar mixing made by a study of the `wrong-sign'
process D0 -> K+pi-. The data come from an integrated luminosity of e+e-
collisions at sqrt{s} of about 10 GeV consisting of 9.0 1/fb recorded with the
CLEO-II.V detector. We measure the time-integrated rate of the `wrong-sign'
process D0 -> K+pi-, relative to that of the Cabibbo-favored process D0bar ->
K+pi-, to be R_ws=(0.34+-0.07+-0.06)%. We study that rate as a function of the
decay time of the D0, to distinguish the rate of direct
doubly-Cabibbo-suppressed decay from D0-D0bar mixing. The amplitudes that
describe D0-D0bar mixing, x' and y', are consistent with zero. The
one-dimensional limits, at the 95% C.L., that we determine are (1/2)x'^2<0.05%,
and -5.9% < y' < 0.3%. All results are preliminary.


title: Measurement of Open Beauty Production at HERA

abstract:
  The first observation of open b production in ep collisions is reported. An
event sample containing muons and jets has been selected which is enriched in
semileptonic b quark decays. The visible cross section \sigma(ep -> b \bar{b}X
-> \mu X') for Q^2 < 1 GeV^2, 0.1 < y < 0.8 is measured to be
0.176+-0.016(stat.)+0.026-0.017(syst.) nb for the muons to be detected in the
range 35 deg < \theta^\mu < 130 deg and \pt^\mu > 2.0 GeV in the laboratory
frame. The expected visible cross section based on a NLO QCD calculation is
0.104+-0.017 nb. The cross sections for electroproduction with Q^2<1 GeV^2 and
photoproduction are derived from the data and found to be \sigma(ep-> e
b\bar{b}X) = 7.1+-0.6(stat.)+1.5-1.3(syst.) nb and \sigma(\gamma p-> b\bar{b}
X) = 111+-10(stat.)+23-20(syst.) at an average <W_{\gamma p}> \sim 180 GeV,
respectively.


title: A Measurement of the W Boson Mass Using Electrons at Large Rapidities

abstract:
  We report a measurement of the W boson mass based on an integrated luminosity
of 82/pb from p-pbar collisions at sqrt(s) = 1.8 TeV recorded in 1994-1995 by
the D0 detector at the Fermilab Tevatron. We identify W bosons by their decays
to e-nu, where the electron is detected in the forward calorimeters. We extract
the mass by fitting the transverse mass and the electron and neutrino
transverse momentum spectra of 11,089 W boson candidates. We measure Mw =
80.691 +- 0.227 GeV. By combining this measurement with our previously
published central calorimeter results from data taken in 1992-1993 and
1994-1995, we obtain Mw = 80.482 +- 0.091 GeV.


title: Propagation of Errors for Matrix Inversion

abstract:
  A formula is given for the propagation of errors during matrix inversion. An
explicit calculation for a 2 by 2 matrix using both the formula and a Monte
Carlo calculation are compared. A prescription is given to determine when a
matrix with uncertain elements is sufficiently nonsingular for the calculation
of the covariances of the inverted matrix elements to be reliable.


title: Study of Charm Production in Z Decays

abstract:
  The production rates of D*+-, Ds*+-, D+-, D0 / D0bar, Ds+, and Lambda_c in Z
to ccbar decays are measured using the LEP I data sample recorded by the ALEPH
detector. The fractional energy spectrum of the D*+- is well described as the
sum of three contributions: charm hadronisation, b hadron decays and gluon
splitting into a pair of heavy quarks. The probability for a c quark to
hadronise into a D*+ is found to be f(c to D*+) = 0.233 +- 0.010 (stat.) +-
0.011 (syst.). The average fraction of the beam energy carried by D*+- mesons
in Z to cc events is measured to be < X_E (D*+-) >_cc = 0.4878 +- 0.0046
(stat.) +- 0.0061 (syst.). The D*+- energy and the hemisphere mass imbalance
distributions are simultaneously used to measure the fraction of hadronic Z
decays in which a gluon splits to a cc pair: n_{gluon to cc} = (3.23 +- 0.48
(stat.) +- 0.53 (syst.) %. The ratio of the Vector/(Vector+Pseudoscalar)
production rates in charmed mesons is found to be P_V = 0.595 +- 0.045. The
fractional decay width of the Z into cc pairs is determined from the sum of the
production rates for various weakly decaying charmed states to be Rc = 0.1738
+- 0.0047 (stat.) +- 0.0116 (syst.).


title: The Bs oscillation amplitude analysis

abstract:
  The properties of the amplitude method for $\Bs$ oscillation analyses are
studied in detail. The world combination of measured amplitudes is converted
into a likelihood profile as a function of oscillation frequency. A procedure
is proposed to estimate the probability that the minimum observed is due to a
statistical fluctuation. This method, applied to the data available at the time
of 1999 Winter Conferences, gives $1 - CL \approx 0.03$ .


title: High Altitude test of RPCs for the ARGO-YBJ experiment

abstract:
  A 50 m**2 RPC carpet was operated at the YangBaJing Cosmic Ray Laboratory
(Tibet) located 4300 m a.s.l. The performance of RPCs in detecting Extensive
Air Showers was studied. Efficiency and time resolution measurements at the
pressure and temperature conditions typical of high mountain laboratories, are
reported.


title: Inelastic diffraction data and the effective Pomeron trajectory

abstract:
  A further analysis of inelastic diffraction data at the ISR and SPS-Collider
confirms the relatively flat s-independent pomeron trajectory in the high-|t|
domain, 1-2 GeV^2, reported earlier by the UA8 Collaboration. At |t| = 1.5
GeV^2, alpha = 0.92 +/- 0.03 is in agreement with the trajectories found in
diffractive photoproduction of vector mesons at HERA. This suggests a universal
fixed Pomeron trajectory at high-|t|. We also show that a triple-Regge
Pomeron-exchange parametrization fit to the data requires an s-dependent
(effective) Pomeron trajectory intercept, alpha(0), which decreases with
increasing s, as expected from unitarization (multi-Pomeron-exchange)
calculations. alpha(0) = 1.10 at the lowest ISR energy, 1.03 at the
SPS-Collider and perhaps smaller at the Tevatron.


title:
Compatibility Analysis of the LSND Evidence and the KARMEN Exclusion for
  numubar->nuebar Oscillations

abstract:
  A combined statistical analysis of the experimental results of the LSND and
KARMEN numubar->nuebar oscillation search is presented. LSND has evidence for
neutrino oscillations that is not confirmed by the KARMEN experiment. However,
there is a region in the (sin^2(2theta),Dm^2) parameter space where the results
of both experiments are statistically compatible. This joint analysis is based
on likelihood functions for both data sets. A frequentist approach creating
Monte Carlo samples analogous to the experimental outcome is applied to deduce
correct confidence limits. Different schemes of combination can be chosen to
provide correct coverage which lead to slightly different confidence regions in
(sin^2(2theta),Dm^2).


title: Hadronic final state interactions at ALEPH and OPAL

abstract:
  The studies of Fermi-Dirac correlations of $\Lambda\Lambda$ and
$\bar{\Lambda}\bar{\Lambda}$ pairs in hadronic $\mathrm{Z}$ decays,
Bose-Einstein correlations and colour reconnection in $\mathrm{W}$-pairs decays
performed by the ALEPH collaboration in $\mathrm{e^+e^-}$ annihilation at LEP
are presented. The OPAL analysis of Bose-Einstein correlations in
$\mathrm{W}$-pair decays is also discussed.


title: Psi(2S) -> pi^+ pi^- J/psi Decay Distributions

abstract:
  Using a sample of 3.8 M psi(2S) events accumulated with the BES detector, the
process psi(2S) -> pi^+ pi^- J/psi is studied. The angular distributions are
compared with the general decay amplitude analysis of Cahn. We find that the
dipion system requires some D-wave, as well as S-wave. On the other hand, the
J/psi-(pi pi) relative angular momentum is consistent with being pure S-wave.
The decay distributions have been fit to heavy quarkonium models, including the
Novikov-Shifman model. This model, which is written in terms of the parameter
kappa, predicts that D-wave should be present. We determine kappa = 0.183 +/-
0.002 +/- 0.003 based on the joint dipion mass - cos theta distribution. The
fraction of D-wave as a function of the dipion mass is found to decrease with
increasing dipion mass, in agreement with the model. We have also fit the
Mannel-Yan model, another model that allows D-wave.


title: The Partonic Structure of the Quasi-Real Photon

abstract:
  New measurements of dijet photoproduction at HERA provide information on the
gluon density in the photon and on its quark densities at high x_gamma and high
factorisation scales.


title: Partial Wave Analysis of $J/\psi\to\gamma(\pi^+\pi^-\pi^+\pi^-)$

abstract:
  BES data on $J/\psi \to \gamma (\pi^{+} \pi^{-} \pi^{+} \pi^{-})$ have been
analyzed into partial waves. We fit with resonances having $J^{PC}=2^{++}$ at
1275 MeV, $0^{++}$ at 1500 MeV, $2^{++}$ at 1565 MeV, $0^{++}$ at 1740 MeV,
$2^{++}$ at 1940 MeV and $0^{++}$ at 2104 MeV, plus a broad $0^-$ component.
The $0^{++}$ resonances decay dominantly to $\sigma\sigma$, while $2^{++}$
resonances in the high mass region decay mainly to $f_2(1270)\sigma$ and
$\sigma\sigma$; $2^{++}$ resonances from the low mass region decay dominantly
to $\rho\rho$.


title:
Evidence for Diffractive Charm Production in nu_mu Fe and nubar_mu Fe
  Scattering at the Tevatron

abstract:
  We present evidence for the diffractive processes nu_mu Fe -> mu^- D_s^+
(D_s^*+) Fe and nubar_mu Fe -> mu^+ D_s^- (D_s^*-) Fe using the Fermilab SSQT
neutrino beam and the Lab E neutrino detector. We observe the neutrino trident
reactions nu_mu Fe -> nu_mu mu^- mu^+ Fe and nubar_mu Fe -> nubar_mu mu^+ mu^-
Fe at rates consistent with Standard Model expectations. We see no evidence for
neutral-current production of J/psi via either diffractive or deep inelastic
scattering mechanisms.


title: Measurement of the Helicity of W Bosons in Top Quark Decays

abstract:
  We use the transverse momentum spectrum of leptons in the decay chain t-->bW
with W-->l nu to measure the helicity of the W bosons in the top quark rest
frame. Our measurement uses a ttbar sample isolated in 106 +/- 4 inverse
picobarns of data collected in ppbar collisions at sqrt(s)=1.8 TeV with the CDF
detector at the Fermilab Tevatron. Assuming a standard V--A weak decay, we find
that the fraction of W's with zero helicity in the top rest frame is F_0 = 0.91
+/- 0.37 (stat) +/- 0.13 (syst), consistent with the standard model prediction
of F_0=0.70 for a top mass of 175 GeV/c**2.


title:
Study of Z Boson Pair Production in e+e- Collisions at LEP at
  \sqrt{s}=189 GeV

abstract:
  The pair production of Z bosons is studied using the data collected by the L3
detector at LEP in 1998 in e+e- collisions at a centre-of-mass energy of 189
GeV. All the visible final states are considered and the cross section of this
process is measured to be 0.74 +0.15 -0.14 (stat.) +/- 0.04 (syst.) pb. Final
states containing b quarks are enhanced by a dedicated selection and their
production cross section is found to be 0.18 +0.09 -0.07 (stat.) +/- 0.02
(syst.) pb. Both results are in agreement with the Standard Model predictions.
Limits on anomalous couplings between neutral gauge bosons are derived from
these measurements.


title: Search for Charged Higgs Bosons in e+e- Collisions at \sqrt{s} = 189 GeV

abstract:
  A search for pair-produced charged Higgs bosons is performed with the L3
detector at LEP using data collected at a centre-of-mass energy of 188.6 GeV,
corresponding to an integrated luminosity of 176.4 pb^-1. Higgs decays into a
charm and a strange quark or into a tau lepton and its associated neutrino are
considered. The observed events are consistent with the expectations from
Standard Model background processes. A lower limit of 65.5 GeV on the charged
Higgs mass is derived at 95 % confidence level, independent of the decay
branching ratio Br(H^{+/-} -> tau nu).


title: Measurement of Rb and BR(b-> l nu X) at LEP Using Double-Tag Methods

abstract:
  We present a combined measurement of Rb = \Gamma(Z -> bb) / \Gamma(Z
->hadrons) and the semileptonic branching ratio of b quarks in Z decays, BR(b->
l nu X), using double-tag methods. Two analyses are performed on one million
hadronic Z decays collected in 1994 and 1995. The first analysis exploits the
capabilities of the silicon microvertex detector. The tagging of b-events is
based on the large impact parameter of tracks from weak b-decays with respect
to the e+e- collision point. In the second analysis, a high-pt lepton tag is
used to enhance the b-component in the sample and its momentum spectrum is used
to constrain the model dependent uncertainties in the semileptonic b-decay. The
analyses are combined in order to provide precise determinations of Rb and
BR(b-> l nu X):
  Rb = 0.2174 +/- 0.0015 (stat.) +/- 0.0028 (sys.);
  BR(b-> l nu X) = (10.16 +/- 0.13 (stat.) +/- 0.30 (sys.)) %.


title: Measurement of direct CP violation with the experiment NA48 at CERN

abstract:
  Direct CP violation is studied in two pion decays of the neutral kaon. Using
data collected in the first beam period in 1997, the result for the parameter
Re(epsilon'/epsilon) is (18.5+/-4.5(stat)+/-5.8(syst))x10^(-4).


title:
Inferring the intensity of Poisson processes at the limit of the
  detector sensitivity (with a case study on gravitational wave burst search)

abstract:
  We consider the issue of reporting the result of search experiment in the
most unbiased and efficient way, i.e. in a way which allows an easy
interpretation and combination of results and which do not depend on whether
the experimenters believe or not to having found the searched-for effect. Since
this work uses the language of Bayesian theory, to which most physicists are
not used, we find that it could be useful to practitioners to have in a single
paper a simple presentation of Bayesian inference, together with an example of
application of it in search of rare processes.

categories: hep-ex astro-ph gr-qc math.PR nucl-ex physics.data-an


title: Current Performance of the SLD VXD3

abstract:
  During 1996, the SLD collaboration completed construction and began operation
of a new charge-coupled device (CCD) vertex detector (VXD3). Since then, its
performance has been studied in detail and a new topological vertexing
technique has been developed. In this paper, we discuss the design of VXD3,
procedures for aligning it, and the tracking and vertexing improvements that
have led to its world-record performance.


title: Recent Tests of QCD at SLD

abstract:
  We present selected results on strong interaction physics from the SLD
experiment at the SLAC Linear Collider. We report on several new studies of 3-
and 4-jet hadronic Z decays, in which jets are identified as quark, antiquark
or gluon. The 3-jet Z^0->b\bar{b}g rate is sensitive to the b-quark mass;
prospects for measuring m_b are discussed. The gluon energy spectrum is
measured over the full kinematic range, providing an improved test of QCD and
limits on anomalous bbg couplings. The parity violation in Z^0->b\bar{b}g
decays is consistent with electroweak theory plus QCD. New tests of T- and
CP-conservation at the bbg vertex are performed. A new measurement of the rate
of gluon splitting into b\bar{b} pairs yields
g_{b\bar{b}}=0.0031+-0.0007(stat.)+-0.0006(syst.) (Preliminary). We also
present a number of new results on jet fragmentation into identified hadrons.
The B hadron energy spectrum is measured over the full kinematic range using a
new, inclusive technique, allowing stringent tests of predictions for its shape
and a precise measurement of <x_B>=0.714+-0.005(stat.)+-0.007(syst.)
(Preliminary). A detailed study of correlations in rapidity y between pairs of
identified pions, kaons and protons confirms that strangeness and baryon number
are conserved locally, and shows local charge conservation between meson-baryon
and strange-nonstrange pairs. Flavor-dependent long-range correlations are
observed for all combinations of these hadron species, yielding new information
on leading particle production. The first study of correlations using
rapidities signed such that y>0 corresponds to the quark direction provides
additional new insights into fragmentation, including the first direct
observation of baryon number ordering along the q\bar{q} axis.


title: Observation of Radiative Leptonic Decay of the Tau Lepton

abstract:
  Using 4.68 fb^{-1} of e^+e^- annihilation data collected with the CLEO II
detector at the Cornell Electron Storage Ring (CESR) we have studied tau
radiative decays tau -> mu nu nu gamma and tau -> e nu nu gamma. For a 10 MeV
minimum photon energy in the tau rest frame, the branching fraction of
radiative tau decay to a muon or electron is measured to be
(3.61+-0.16+-0.35)*10^{-3} or (1.75+-0.06+-0.17)*10^{-2}, respectively. The
branching fractions are in agreement with the Standard Model theoretical
predictions.


title:
Search for Chargino and Neutralino Production at sqrt{s} = 189 GeV at
  LEP

abstract:
  A search for charginos and neutralinos, predicted by supersymmetric theories,
is performed using a data sample of 182.1 pb-1 taken at a centre-of-mass energy
of 189 GeV with the OPAL detector at LEP. No evidence for chargino or
neutralino production is found. Upper limits on chargino and neutralino pair
production cross-sections are obtained as a function of the chargino mass, the
lightest neutralino mass and the second lightest neutralino mass. Within the
Constrained Minimal Supersymmetric Standard Model framework, and for a chargino
- neutralino mass difference of more than 5 GeV, the 95% confidence level lower
limits on the chargino mass are 93.6 GeV for tan{beta} = 1.5 and 94.1 GeV for
tan{beta} = 35. These limits are obtained assuming a universal scalar mass m_0
> 500 GeV. The corresponding limits for all m_0 are 78.0 and 71.7 GeV. The 95%
confidence level lower limits on the lightest neutralino mass, valid for any
value of tan{beta} are 32.8 GeV for m_0 > 500 GeV and 31.6 GeV for all m_0.


title:
Search for Anomalous Production of Acoplanar Di-lepton Events in e+e-
  Collisions at sqrt{s} = 183 and 189 GeV

abstract:
  A selection of di-lepton events with significant missing transverse momentum
has been performed using a total data sample of 237.4 pb-1 at e+e-
centre-of-mass energies of 183 GeV and 189 GeV. The observed numbers of events
- 78 at 183 GeV and 301 at 189 GeV - are consistent with the numbers expected
from Standard Model processes, which arise predominantly from W+W- production
with each W decaying leptonically. This topology is also an experimental
signature for the pair production of new particles that decay to a charged
lepton accompanied by one or more invisible particles. Discrimination
techniques are described that optimise the sensitivity to particular new
physics channels. No evidence for new phenomena is apparent and model
independent limits are presented on the production cross-section times
branching ratio squared for sleptons and for leptonically decaying charginos
and charged Higgs. Assuming a 100 % branching ratio for the decay of a slepton
to a lepton and the lightest neutralino, we exclude at 95 % CL: right-handed
smuons with masses below 82.3 GeV for a smuon-neutralino mass difference > 3
Gev and right-handed staus with masses below 81.0 GeV for a stau-neutralino
mass difference > 8 GeV. Right-handed selectrons are excluded at 95% CL for
masses below 87.1 GeV for a selectron-neutralino mass diffeerence > 5GeV,
within the framework of the Minimal Supersymmetric Standard Model assuming mu <
-100 GeV and tan{beta} = 1.5. Charged Higgs bosons are excluded at 95% CL for
masses below 82.8GeV, assuming a 100% branching ratio for their decay to
tau+neutrino.


title: Precise Electroweak Measurements at the Z0 Pole

abstract:
  Over the last decade, precise LEP and SLC measurements of electroweak
coupling parameters at the Z0 pole have lead to tests of the Standard Model to
unprecedented precision. This report presents a comprehensive review of these
studies, including a review of relevant Z0 pole physics issues, facilities,
instrumentation, and the measurements made. Global fits for the Higgs Boson
mass and Z0-b coupling parameters are also presented.


title: Tracking and Vertexing at a High Energy Linear Collider

abstract:
  The relative merits and disadvantages of various alternatives for vertexing
and central tracking detectors for the Linear Collider detector are presented.
Research and development prospects for the various alternatives are also
discussed, as well as a preliminary study of the prospects for forward
(cos(theta) > 0.9) tracking.


title:
The process $e^+e^-\to\pi^+\pi^-\pi^0$ in the energy range 2E_0=1.04 -
  1.38 GeV

abstract:
  In the experiment with the SND detector at VEPP-2M e^+e^- collider the
process $e^+e^-\to\pi^+\pi^-\pi^0$ was studied in the energy range 2E_0 from
1.04 to 1.38 GeV. A broad peak was observed with the visible mass
$M_{vis}=1220\pm 20$ MeV and cross section in the maximum $\sigma_0\simeq 4$
nb. The peak can be interpreted as a $\omega$-like resonance $\omega (1200)$.


title:
Prospects of Scintillating Crystal Detector in Low-Energy Low-Background
  Experiments

abstract:
  Scintillating crystal detector offers potential advantages in low-energy
(keV-MeV range) low-background experiments for particle physics and
astrophysics. The merits are discussed using CsI(Tl) crystal as illustrations.
The various physics topics which can be pursued with this detector technology
are summarized. A conceptual design for a generic detector is presented.


title: Recent results on J/Psi, Psi(2S) and Upsilon production at CDF

abstract:
  CDF has obtained new results on quarkonium production in p\bar{p} collisions
at \sqrt{s} = 1.8 TeV. We report on measurements of Upsilon meson production,
Upsilon(1S) production from Chi_b feeddown, and the production polarization of
Upsilon(1S), J/Psi and Psi(2S) mesons.


title:
Search for a W' Boson via the Decay Mode W' -> mu nu in 1.8 TeV p-pbar
  Collisions

abstract:
  We report the results of a search for a W' boson produced in p-pbar
collisions at a center-of-mass energy of 1.8 TeV using a 107 pb-1 data sample
recorded by the Collider Detector at Fermilab. We consider the decay channel W'
-> mu nu and search for anomalous production of high transverse mass mu-nu
lepton pairs. We observe no excess of events above background and set limits on
the rate of W' boson production and decay relative to Standard Model W boson
production and decay using a fit of the transverse mass distribution observed.
If we assume Standard Model strength couplings of the W' boson to quark and
lepton pairs, we exclude a W' boson with invariant mass less than 660 GeV/c**2
at 95% confidence level.


title: Production of J/psi Mesons in p Be Collisions at 530 and 800 GeV/c

abstract:
  We report on the production of J/psi mesons in 530 and 800 GeV/c proton - Be
collisions in the Feynman-x range 0.0 < xf < 0.6. The J/psi mesons were
detected via decays into opposite sign muon pairs. Differential distributions
for J/psi production have been measured as functions of xf, pT^2, and cosine of
the Gottfried-Jackson decay angle. These distributions are compared with
results on J/psi production obtained in 515 GeV/c pion - Be collisions,
measured by the same experiment, as well as with results from other experiments
using incident protons.


title: Search for Scalar Leptons in e+e- collisions at \sqrt{s}=189 GeV

abstract:
  We report the result of a search for scalar leptons in e+e- collisions at 189
GeV centre-of-mass energy at LEP. No evidence for such particles is found in a
data sample of 176 pb^{-1}. Improved upper limits are set on the production
cross sections for these new particles. New exclusion contours in the parameter
space of the Minimal Supersymmetric Standard Model are derived, as well as new
lower limits on the masses of these supersymmetric particles. Under the
assumptions of common gaugino and scalar masses at the GUT scale, we set an
absolute lower limit on the mass of the lightest scalar electron of 65.5 GeV


title:
Search for Charginos and Neutralinos in e+e- collisions at \sqrt{s} =
  189 Gev

abstract:
  We report the result of a search for charginos and neutralinos, in e+e-
collisions at 189 GeV centre-of-mass energy at LEP. No evidence for such
particles is found in a data sample of 176 pb^{-1}. Improved upper limits for
these particles are set on the production cross sections. New exclusion
contours in the parameter space of the Minimal Supersymmetric Standard Model
are derived, as well as new lower limits on the masses of these supersymmetric
particles. Under the assumptions of common gaugino and scalar masses at the GUT
scale, we set an absolute lower limit on the mass of the lightest neutralino of
32.5 GeV and on the mass of the lightest chargino of 67.7 GeV.


title: Measurement of Triple-Gauge-Boson Couplings of the W Boson at LEP

abstract:
  We report on measurements of the triple-gauge-boson couplings of the W boson
in e+e- collisions with the L3 detector at LEP. W-pair, single-W and
single-photon events are analysed in a data sample corresponding to a total
luminosity of 76.7 pb^{-1} collected at centre-of-mass energies between 161 GeV
and 183 GeV. CP-conserving as well as both C- and P-conserving
triple-gauge-boson couplings are determined. The results, in good agreement
with the Standard-Model expectations, confirm the existence of the self
coupling among the electroweak gauge bosons and constrain its structure.


title:
Single and Multi-Photon Events with Missing Energy in e+e- Collisions at
  \sqrt{s} = 189 GeV

abstract:
  Single and multi-photon events with missing energy are analysed using data
collected with the L3 detector at LEP at a centre-of-mass energy of 189 GeV,
for a total of 176 pb^{-1} of integrated luminosity. The cross section of the
process e+e- -> nu nu gamma (gamma) is measured and the number of light
neutrino flavours is determined to be N_\nu = 3.011 +/- 0.077 including lower
energy data. Upper limits on cross sections of supersymmetric processes are set
and interpretations in supersymmetric models provide improved limits on the
masses of the lightest neutralino and the gravitino. Graviton-photon production
in low scale gravity models with extra dimensions is searched for and limits on
the energy scale of the model are set exceeding 1 TeV for two extra dimensions.


title: Gamma-gamma, gamma-electron colliders: physics, luminosities, background

abstract:
  This report on Photon Colliders covers the following ``physics'' issues:
physics motivation, possible luminosities, backgrounds, plans of works and
international cooperation. More technical aspects such as accelerator issues,
new ideas on laser optics, laser cooling, and interaction region layout are
discussed in my second talk at this Workshop.


title:
Gamma-gamma, gamma-electron colliders: accelerator, laser and
  interaction region issues

abstract:
  In this report on Photon Colliders the following technical aspects are
considered: special requirements to an accelerator, new ideas on laser optics,
laser cooling, and interaction region layout issues. In fact it is continuation
of my first talk at this workshop where physics motivation, possible
luminosities and backgrounds were discussed.


title: Search for excited fermions and leptoquarks at HERA

abstract:
  Recent results on searches for new particles at the electron-proton collider
HERA are reported. Based on roughly 40pb-1 of e^+p data taken in the years
1994-1997, the H1 and ZEUS collaborations have derived new exclusion limits for
the direct production of excited fermion states and of leptoquarks in different
decay channels, including lepton-flavor violating decays. The results of
searches for contact interactions further constrain the parameter space for
such particles and their couplings in the high-mass regime, where direct
production is kinematically prohibited. Also preliminary analyses of the e^-p
data taken in 1998 and 1999 do not find signals of new physics.


title: A New Limit on CPT Violation

abstract:
  A search for antiproton decay has been made at the Fermilab Antiproton
Accumulator. Limits are placed on fifteen antiproton decay modes. The results
are used to place limits on the characteristic mass scale Mx that could be
associated with CPT-violation accompanied by baryon number violation.


title: Determination of the Phase of Vub from Charmless Hadronic B Decay Rates

abstract:
  We perform a model dependent fit to recent data on charmless hadronic B
decays and determine $\gamma$, the phase of $V^*_{ub}$. We find $\gamma =
114^{+25}_{-21}$ degrees, which disfavors the often quoted $\gamma \sim
60^\circ$ at the two standard deviation level. We also fit for the form factors
$F_0^{B\pi}$ and $A_0^{B\rho}$, and the strange-quark mass. They are consistent
with theoretical expectations, although $m_s$ is somewhat low. Such agreement
and the good $\chi^2$ for the fit may be interpreted as a confirmation of the
adequacy of our model assumptions.


title: Hadronic Shower Development in Tile Iron-Scintillator Calorimetry

abstract:
  The lateral and longitudinal profiles of hadronic showers detected by a
prototype of the ATLAS Iron-Scintillator Tile Hadron Calorimeter have been
investigated. This calorimeter uses a unique longitudinal configuration of
scintillator tiles. Using a fine-grained pion beam scan at 100 GeV, a detailed
picture of transverse shower behavior is obtained. The underlying radial energy
densities for four depth segments and for the entire calorimeter have been
reconstructed. A three-dimensional hadronic shower parametrization has been
developed. The results presented here are useful for understanding the
performance of iron-scintillator calorimeters, for developing fast simulations
of hadronic showers, for many calorimetry problems requiring the integration of
a shower energy deposition in a volume and for future calorimeter design.


title:
Measurement of the Inclusive Charm Cross Section at 4.03 GeV and 4.14
  GeV

abstract:
  The cross section for charmed meson production at $\sqrt{s} = 4.03 $ and 4.14
GeV has been measured with the Beijing Spectrometer. The measurement was made
using 22.3 $pb^{-1}$ of $e^+e^-$ data collected at 4.03 GeV and 1.5 $pb^{-1}$
of $e^+e^-$ data collected at 4.14 GeV. Inclusive observed cross sections for
the production of charged and neutral D mesons and momentum spectra are
presented. Observed cross sections were radiatively corrected to obtain tree
level cross sections. Measurements of the total hadronic cross section are
obtained from the charmed meson cross section and an extrapolation of results
from below the charm threshold.


title: Search for Physics Beyond Standard Model at HERA

abstract:
  The latest status of searches at HERA for physics beyond the Standard Model
is summarized on behalf of the H1 and ZEUS collaborations. Emphasis is put on
production of resonant particles accessible within the HERA center-of-mass
energy, such as leptoquarks, squarks in R-parity-violating supersymmetry or
excited fermions. Most of the results presented here are based on the full
available statistics of positron-proton collisions, and also preliminary
results from very recent electron-proton running are presented. Results which
have been updated since this Ringberg '99 Workshop are also included.


title: Photoproduction at low Q^2

abstract:
  The past year has seen a number of important developments in hard
photoproduction physics at the HERA Collider. These are surveyed.


title: High resolution pixel detectors for e+e- linear colliders

abstract:
  The physics goals at the future e+e- linear collider require high performance
vertexing and impact parameter resolution. Two possible technologies for the
vertex detector of an experimental apparatus are outlined in the paper: an
evolution of the Hybrid Pixel Sensors already used in high energy physics
experiments and a new detector concept based on the monolithic CMOS sensors.


title: Searches for Scalar Quarks in e^+e^- Interactions at \sqrt{s} = 189 GeV

abstract:
  Searches for scalar top and scalar bottom quarks, as well as for
mass-degenerate scalar quarks of the first two families are performed at 189
GeV centre-of-mass energy with the L3 detector at LEP. No signals are observed.
Model-independent limits on the scalar top production cross sections are
determined for the decay modes t1~ -> c chi_1^0 and t1~ -> b l nu~. For scalar
quarks of the other flavours q~ -> q chi_1^0 decays are considered. Within the
framework of the Minimal Supersymmetric Standard Model mass limits are set at
95% C.L. for these particles. Indirect limits on the gluino mass are also
derived.


title: Search for Excited Leptons at \sqrt{s} = 189 GeV

abstract:
  A search for excited leptons, e*, mu*, tau*, nu_e*, nu_mu*, and nu_tau* was
performed with the L3 detector at LEP using data collected at a centre-of-mass
energy of 189 GeV, corresponding to an integrated luminosity of 176 pb^{-1}. No
evidence of their production is observed. From the searches for pair produced
excited leptons, lower mass limits are set close to the kinematic limit. From
the searches for singly produced excited leptons, upper limits on their
couplings are derived in the mass range up to 189 GeV.


title: Electroweak and CP violation physics at a Linear Collider Z-factory

abstract:
  A future linear collider such as TESLA may be able to run on the Z0 resonance
with very high luminosity and polarised electron and positron beams. The
possibilities of measuring electroweak quantities with high precision are
investigated. Huge improvements with respect to the present precision can be
expected, especially for the asymmetries A_LR and A_b where beam polarisation
can be exploited. The very large sample of Z to bbbar events also allows
studies of various CP-violating b decays. The precision achievable on the CKM
unitarity triangle angles is comparable to experiments at b factories and
future hadron colliders.


title: QCD with SLD

abstract:
  We present selected new results on strong interaction physics from the SLD
experiment at the SLAC Linear Collider (SLC), symmetry tests of b\bar{b}g
vertex, the rate of secondary b\bar{b} production via gluon splitting, the B
hadron energy spectrum and rapidity correlations between identified charged
hadrons. The parity violation in Z0 --> b\bar{b}g decays is consistent with
electroweak theory plus QCD. New tests of T- and CP-conservation at the
b\bar{b}g vertex are performed. A new measurement of the rate of gluon
splitting into b\bar{b} pairs yields g_{b\bar{b}}=0.00307 +- 0.00071 (stat.) +-
0.00066 (syst.) (Preliminary). The B hadron energy spectrum is measured using a
new inclusive technique, allowing tests of predictions for its shape and a
measurement of < x_B > = 0.714 +- 0.005 (stat.) +- 0.007 (syst.) (Preliminary).
A study of correlations in rapidity between pairs of identified pions, kaons
and protons confirms that strangeness and baryon number areconserved locally,
and shows local charge conservation between meson-baryon and strange-nonstrange
pairs. Flavor-dependent long-range correlations are observed for all
combinations of these hadron species. The first study of correlations using
signed rapidities is done and find the first direct observation of baryon
number ordering along the q\bar{q} axis.


title: Diffractive Dissociation of High Momentum Pions

abstract:
  The diffractive dissociation of 500 GeV/c $\pi^-$ into di-jets is described
as a way to measure the momentum distribution of quarks in the pion. The
measurements of the pion diffractive dissociation were carried out using data
from Fermilab E791. Preliminary results show that the $|q\bar {q}>$ Asymptotic
wave function which was developed using perturbative QCD methods describes the
data well for $Q^2 \sim 10 ~{\rm (GeV/c)^2}$. At these values signals of color
transparency are expected and, indeed, observed through the $A$-dependence of
the yield of the diffractive di-jets.


title:
Production of Y(1S) Mesons from chib Decays in pp(bar) Collisions at
  sqrt(s)=1.8 TeV

abstract:
  We have reconstructed the radiative decays $\chi_{b}(1P) \to \Upsilon(1S)
\gamma $ and $\chi_{b}(2P) \to \Upsilon(1S) \gamma $ in $p \bar{p}$ collisions
at $\sqrt{s} = 1.8$ TeV, and measured the fraction of $\Upsilon(1S)$ mesons
that originate from these decays. For $\Upsilon(1S)$ mesons with
$p^{\Upsilon}_{T}>8.0$ GeV/$c$, the fractions that come from $\chi_{b}(1P)$ and
$\chi_{b}(2P)$ decays are $(27.1\pm6.9(stat)\pm4.4(sys))%$ and
$(10.5\pm4.4(stat)\pm1.4(sys))%$, respectively. We have derived the fraction of
directly produced $\Upsilon(1S)$ mesons to be $(50.9\pm8.2(stat)\pm9.0(sys))%$.


title: Search for nucleon decay into lepton + K0 final states using Soudan 2

abstract:
  A search for nucleon decay into two-body final states containing K^0 mesons
has been conducted using the 963 metric ton Soudan 2 iron tracking calorimeter.
The topologies, ionizations, and kinematics of contained events recorded in a
5.52 kiloton-year total exposure (4.41 kton-year fiducial volume exposure) are
examined for compatibility with nucleon decays in an iron medium. For proton
decay into the fully visible final states \mu^+K^0_s and e^+K^0_s, zero and one
event candidates are observed respectively. The lifetime lower limits (\tau /B)
thus implied are 1.5 \times 10^{32} years and 1.2 \times 10^{32} years,
respectively. Lifetime lower limits are also reported for proton decay into
l^+K^0_l, and for neutron decay into \nu K^0_s.


title: Recent Charmonium Results from BES

abstract:
  This paper summarizes recent results obtained from the BES psi(2S) data,
which with 3.8 M events, is the world's largest data set. Distributions for
psi(2S) -> pi^+ pi^- J/psi are fit to the Novikov-Shifman model. Preliminary
branching fractions are reported for psi(2S) -> gamma f_2(1270) and gamma
f_J(1710), as well as for decays into states containing an omega or phi.
Finally recent measurements of the mass of the chi_c0 and eta_c are reported.


title: D0 Upgrade for RUN II

abstract:
  The D0 detector at The Fermilab Tevatron is undergoing a major upgrade to
prepare for data taking with luminosities reaching 2 x 10^{32} cm^{-2} s^{-1}.
The upgrade includes a new central tracking array, new muon detector components
and electronic upgrades to many subsystems. The D0 upgraded detector will be
operational for RUN II in spring 2000.


title: Recent results from D0 on the top quark

abstract:
  We describe three recent results from D0 related to the top quark: a
preliminary measurement of the t-tbar spin correlation in top quark pair
production, a search for top quark decays into charged Higgs bosons, and an
improved cross section analysis in the t-tbar -> e mu channel using neural
networks.


title: Search for the Weak Decay of a Lightly Bound H Dibaryon

abstract:
  We present results of a search for a neutral, six-quark, dibaryon state
called the \h, a state predicted to exist in several theoretical models.
Observation of such a state would signal the discovery of a new form of
hadronic matter. Analyzing data collected by experiment E799-II, using the KTeV
detector at Fermilab, we searched for the decay $H^0 \to \Lambda p \piminus$
and found no candidate events. We exclude the region of lightly bound mass
states just below the $\Lambda\Lambda$ mass threshold, $2.194~\gev < M_H <
2.231$~\gev, with lifetimes from $\sim$$ 5 \times 10^{-10}$~sec to $\sim$$1
\times 10^{-3}$~sec.


title: Is there new physics in the 1999 ALEPH data ?

abstract:
  The first results on searches performed by ALEPH on the 1999 data sample are
presented here. They are based on an integrated luminosity of about 54 pb$^-1$
collected at the two centre-of-mass energies of 192 and 196 GeV. Preliminary
results on searches for supersymmetric particles and for the neutral Higgs
bosons are shown.


title: Recent N^* Results From J/\psi Decays

abstract:
  Based on 7.8 million J/\psi events collected at BEPC, the events for J/\psi
\to p\bar{p}\pi^0 and p\bar{p}\eta have been selected and reconstructed. Clear
peaks are observed around 1480 MeV in p\pi^0 (\bar{p}\pi^0) invariant mass
spectrum and near the threshold for $\eta$ production in p\eta(\bar{p}\eta)
invariant mass spectrum. A partial wave analysis of J/\psi \to p\bar{p}\eta
data has been performed. Two J^P={1/2}^- resonances are observed with mass and
width (M, \Gamma) at (1540^{+15}_{-17}, 178^{+20}_{-22}) MeV and
(1648^{+18}_{-16}, 150)MeV, and are considered to be the nucleon resonances
S_{11}(1535) and S_{11}(1650) respectively.


title: Tau Jet Signals for Supersymmetry at the Tevatron

abstract:
  We present a more detailed account of our study (hep-ph/9903238) for the
supersymmetry reach of the Tevatron in channels with isolated leptons and
identified tau jets. We review the theoretical motivations for expecting such
signatures, and describe the relevant parameter space in the minimal
supergravity and the minimal gauge-mediated models. With explicit Monte Carlo
simulations we then show that for certain parameter ranges, channels with two
leptons and one tau jet offer a better reach in Run II than the clean trilepton
signal. We emphasize than improving on tau ID is an important prerequisite for
successful searches in multiple tau jet channels. Finally, we discuss some
triggering issues.


title: Search for Exotics at the Tevatron: Present and Future

abstract:
  We present recent results on searches for non-SUSY new physics at the CDF and
D0 Collaborations in the 1992-1996 Fermilab Tevatron run. While no compelling
evidence for existence of new physics was found, the Tevatron data have
excluded a significant region of the theoretically allowed phase space for a
variety of non-SUSY extensions of the Standard Model. Tight limits on the
existence of the following new phenomena are set: leptoquarks of all three
generations, quark-lepton compositeness, 4-th generation quarks, fermiophobic
Higgs, technicolor, etc. Prospects of the Tevatron experiments in Run II are
discussed.


title: Production of excited charmed mesons at LEP

abstract:
  Studies od the production of orbitally excited charmed and charmed strange
mesons in e+e- collisions, performed by the LEP collaborations are reviewed.
Measurements of the production rates of orbitally excited charmed mesons in
semileptonic b decays are presented. Searches for charmed meson radial
excitations are also briefly discussed.


title:
Sceptical combination of experimental results: General considerations
  and application to epsilon-prime/epsilon

abstract:
  This paper is meant as a contribution to the often debated subject of how to
combine data which appear to be in mutual disagreement. As a practical example,
the epsilon-prime/epsilon determinations have been considered.

categories: hep-ex astro-ph cond-mat hep-ph nucl-ex physics.data-an


title: W and Z Properties at the Tevatron

abstract:
  We present recent results from CDF and D0 on W and Z production cross
sections, the width of the W boson, tau-e universality in W decays, trilinear
gauge boson couplings, and on the observation of Z -> b bbar.


title:
Measurement of diffractive photoproduction of vector mesons at large
  momentum transfer at HERA

abstract:
  Elastic and proton-dissociative photoproduction of $\rho^0$, $\phi$ and
$J/\psi$ vector mesons ($\gamma p\to Vp$, $\gamma p\to VN$, respectively) have
been measured in e^+p interactions at HERA up to -t=3 GeV$^2$, where t is the
four-momentum transfer squared at the photon-vector meson vertex. The analysis
is based on a data sample in which photoproduction reactions were tagged by
detection of the scattered positron in a special-purpose calorimeter. This
limits the photon virtuality, Q^2, to values less than 0.01 GeV$^2$, and
selects a $\gamma p$ average center-of-mass energy of <W> = 94 GeV. Results for
the differential cross sections, d$\sigma$/d$t$, for $\rho^0$, $\phi$ and
$J/\psi$ mesons are presented and compared to the results of recent QCD
calculations. Results are also presented for the t-dependence of the pion-pair
invariant-mass distribution in the $\rho^0$ mass region and of the spin-density
matrix elements determined from the decay-angle distributions. The Pomeron
trajectory has been derived from measurements of the W dependence of the
elastic differential cross sections d$\sigma$/d$t$ for both $\rho^0$ and $\phi$
mesons.


title: Charm hadroproduction results from Selex

abstract:
  The SELEX experiment (E781) is 3-stage magnetic spectrometer for a high
statistics study of hadroproduction of charm baryons out to large x_F using 650
Gev Sigma-, pi- and p beams. The main features of the spectrometer are: a high
precision silicon vertex system, powerful particle identification provided by
TRD and RICH, forward Lambda decay spectrometer and 3-stage lead glass photon
detector. An experiment overview and spectrometer features are shown.
Reconstructed charm states and results on Lambda_c, D+ particles and
antiparticles produced by Sigma-, pi- and p beams at x_F>0.3 and asymmetry for
Lambda_c are presented.


title:
Search for Second Generation Leptoquark Pairs in pbar-p Collisions at
  sqrt(s) = 1.8 TeV

abstract:
  We have searched for second generation leptoquark (LQ) pairs in the
\mu\mu+jets channel using 94+-5 pb^{-1} of pbar-p collider data collected by
the D0 experiment at the Fermilab Tevatron during 1993-1996. No evidence for a
signal is observed. These results are combined with those from the \mu\nu+jets
and \nu\nu+jets channels to obtain 95% confidence level (C.L.) upper limits on
the LQ pair production cross section as a function of mass and $beta, the
branching fraction of a LQ decay into a charged lepton and a quark. Lower
limits of 200(180) GeV/c^2 for \beta=1(1/2) are set at the 95% C.L. on the mass
of scalar LQ. Mass limits are also set on vector leptoquarks as a function of
\beta.


title:
The Statistical Analysis of Gaussian and Poisson Signals Near Physical
  Boundaries

abstract:
  We propose a construction of frequentist confidence intervals that is
effective near unphysical regions and unifies the treatment of two-sided and
upper limit intervals. It is rigorous, has coverage, is computationally simple
and avoids the pathologies that affect the Likelihood Ratio and related
constructions. Away from non-physical regions, the results are exactly the
usual central two-sided intervals. The construction is based on including the
physical constraint in the derivation of the estimator, leading to an estimator
with values that are confined to the physical domain.


title: Chooz, Palo Verde, Krasnoyarsk

abstract:
  This is a short review of the present ~ 1 km baseline oscillation
experi-ments at nuclear reactors. An idea of a new search for very small mixing
angle oscillations at Krasnoyarsk is also mentioned.