title:
Measurement of the Proton Structure Function F2 and of the Total
  Photon-Proton Cross Section sigma(tot) at Very Low Q2 and Very Low x

abstract:
  The proton structure function F2 has been measured in the range 0.045 GeV2 <
Q2 < 0.65 GeV2 and 6*10**-7 < x < 1*10**-3 using 3.9 pb-1 of ep->eX reactions
recorded with the ZEUS detector in 1997. The analysis is based on data from the
Beam Pipe Calorimeter (BPC) and the Beam Pipe Tracker (BPT). Compared to our
previous analysis, the BPT permits improved background suppression and better
control of systematic uncertainties, allowing the extension of the kinematic
region of the measurement towards lower Q2 as well as higher and lower y.
Significant improvements have also been achieved in the simulation of the
hadronic final state via a mixture of samples of non-diffractive and
diffractive Monte Carlo events, generated by the programs DJANGO and RAPGAP.


title: Measurement of $B\to \rho\ell\nu$ Decay and $|V_{ub}|$

abstract:
  Using a sample of 3.3 million Upsilon(4S) -> BBbar events collected with the
CLEO II detector at the Cornell Electron Storage Ring (CESR), we measure the
branching fraction for B -> rho l nu, |V_ub|, and the partial rate (Delta
Gamma) in three bins of q^2 = (p_B-p_rho)^2. We find B(B^0 -> rho^- l^+
nu)=(2.69 +- 0.41^+0.35_-0.40 +- 0.50) 10^-4, |V_ub|=(3.23 +- 0.24^+0.23_-0.26
+- 0.58) 10^-3, Delta Gamma (0 < q^2 < 7 GeV^2/c^4) =(7.6 +- 3.0 ^+0.9_-1.2 +-
3.0) 10^-2 ns^-1, Delta Gamma (7 < q^2 < 14 GeV^2/c^4) =(4.8 +- 2.9 ^+0.7_-0.8
+- 0.7) 10^-2 ns^-1, and Delta Gamma (14 < q^2 < 21 GeV^2/c^4) = (7.1 +-
2.1^+0.9_-1.1 +- 0.6)10^-2 ns^-1. The quoted errors are statistical,
systematic, and theoretical. The method is sensitive primarily to B -> rho l nu
decays with leptons in the energy range above 2.3 GeV. Averaging with the
previously published CLEO results, we obtain B(B^0 -> rho^- l^+ nu) = (2.57 +-
0.29^+0.33_-0.46 +- 0.41) 10^-4 and |V_{ub}| = (3.25 +- 0.14 ^+0.21_-0.29 +-
0.55) 10^-3.


title:
A preliminary measurement of the gluon splitting rate into $b\bar{b}$
  pairs in hadronic $Z^0$ decays

abstract:
  We present a measurement of the rate of gluon splitting into bottom quarks,
$g \to b\bar{b}$, in hadronic $Z^0$ decays collected by SLD from 1996 to 1998.
The analysis was performed by looking for secondary bottom production in 4-jet
events of any primary flavor. A topological vertex mass technique was used to
tag the two jets with the smallest angle between them as $b/\bar{b}$. We
obtained a rate of $g \to b\bar{b}$ per hadronic event to be $(3.07 \pm 0.71
{\rm (stat.)} \pm 0.66 {\rm (syst.)})\times 10^{-3}$ (preliminary).


title: Tests of QCD using Heavy Flavors at SLD

abstract:
  We present preliminary results on three SLD analyses: the gluon energy
spectrum in 3-jet bbg events, the rate of g->bb, and the b fragmentation
function in Z0 decays. The gluon energy spectrum, measured over the full
kinematic range, is compared with perturbative QCD predictions. We set new 95%
C.L. limits on the anomalous chromomagnetic coupling of the b quark:
-0.09<kappa<0.06. The rate of g->bb is measured to be (3.07 +/- 0.71(stat) +/-
0.66(syst)) X 10^-3. The inclusive B hadron energy distribution in Z0 decays is
measured for the first time over the full kinematic range, using a novel B
hadron energy reconstruction technique. Several models of b fragmentation
including JETSET + Peterson are excluded by the data. The average scaled B
hadron energy of the weakly decaying B hadron is measured to be XB = 0.713 +/-
0.005(stat) +/- 0.007(syst) +/- 0.002 (model). All three measurements take
advantage of the small and stable SLC interaction point as well as the
excellent vertexing and tracking capabilities of the upgraded CCD-pixel vertex
detector.


title: The QED Structure of the Photon

abstract:
  Measurements of the QED structure of the photon based on the reaction ee -->
ee \gamma(*)(P^2)\gamma*(Q^2) --> ee mumu are discussed.
  This review is an update of the discussion of the results on the QED
structure of the photon presented in Refs.[1], and covers the published
measurements of the photon structure functions F_2, F_A nd F_B and of the
differential cross-section dsig/dx for the exchange of two virtual photons.


title: Observation of Direct CP Violation in K_{S,L} to \pi \pi Decays

abstract:
  We have compared the decay rates of K_L and K_S to \pi^+ \pi^- and \pi^0
\pi^0 final states using a subset of the data from the KTeV experiment (E832)
at Fermilab. We find that the direct-CP-violation parameter
Re(\epsilon'/\epsilon) is equal to (28.0 \pm 3.0 (stat) \pm 2.8 (syst)) \times
10^{-4}. This result definitively establishes the existence of CP violation in
a decay process.


title: Fragmentation in DIS

abstract:
  The fragmentation properties in deep-inelastic scattering (DIS) at HERA are
investigated in order to test perturbative QCD and quark fragmentation
universality. Selected results for the inclusive single particle distributions
and the angular two-particle correlations in the current region of the Breit
frame are presented and compared to results from $e^{+}e^{-}$ collisions. The
extension of the DIS fragmentation studies to the target region of the Breit
frame are also reported.


title: Forward pi^0-meson production at HERA

abstract:
  The production of high transverse momentum piz^0-mesons has been measured in
deep-inelastic e-p scattering events at low Bjorken-$x$ taken with the
  H1 detector at HERA. The production of high p_T particles is strongly
correlated to the emission of hard partons in QCD and is therefore sensitive to
the dynamics of the strong interaction. For the first time the measurement of
single particles has been extended to the region of small angles w.r.t. the
proton remnant (forward region) and down to very low values of x ~ 5x10^-5.
This region is expected to be particularly sensitive to QCD evolution effects
in final states. Differential cross sections of inclusive pi^0-meson production
have been measured as a function of Bjorken-x and the four-momentum transfer
Q^2, and also as a function of the transverse momentum and the polar angle of
the pi^0-mesons. A recent BFKL calculation and QCD models based on the DGLAP
splitting functions are compared to the data. The best description of the data
is achieved by the BFKL calculation.


title: Jet Physics at HERA

abstract:
  Measurements of inclusive jet and dijet cross sections in photoproduction and
deep inelastic scattering are presented. These measurements provide new tests
of QCD, constrain the parton densities of the proton and the photon, and allow
the search for new physics. Measurements of jet shapes are reported and used to
test the differences between quark and gluon jets.


title: The CP/T Experiment

abstract:
  In this talk I describe a proposed Fermilab Main Injector experiment to carry
out a program of measurements on the physics of K^0 mesons. The experiment is
designed to maximize the interference between K_L and K_S mesons near their
production target, and hence have excellent sensitivity to CP violation in many
decay modes. The extremely accurate CP violation measurements we will be able
to make will allow us to test CPT symmetry violation with sensitivity at the
Planck scale.
  The experiment will use an RF-separated K^+ beam striking a target at the
entrance to a hyperon magnet to make the K^0 beam by charge exchange. The decay
region, magnetic spectrometer, electromagnetic calorimeter, and muon detector
follow immediately to observe interference between K_L and K_S near the target.


title: Event Shapes and Power Corrections in ep DIS

abstract:
  Deep-inelastic ep scattering data, taken with the H1 detector at HERA, are
used to study the event shape variables thrust, jet broadening, jet mass, C
parameter, and two kinds of differential two-jet rates over a large range of
``relevant energy'' Q between 7 GeV and 100 GeV. The Q dependence of the mean
values is fit to second order calculations of perturbative QCD applying power
law corrections proportional to 1/Q^p to account for hadronization effects. The
concept of these power corrections is tested by a systematic investigation in
terms of a non-perturbative parameter alpha_{p-1} and the strong coupling
constant.


title: MiniBooNE: the Booster Neutrino Experiment

abstract:
  The Booster Neutrino Experiment at Fermilab is preparing to search for muon
to electron neutrino oscillations. The experiment is designed to make a
conclusive statement about LSND's neutrino oscillation evidence. The
experimental prospects are outlined in light of the current results from LSND
and KARMEN.


title:
Uncertainties in the measurements of the Inclusive Jet Cross Section at
  the Tevatron

abstract:
  The systematic uncertainties of the measurements of the Inclusive Jet Cross
Section at the Tevatron and their effect on the chi^2 comparisons between data
and theoretical predictions are discussed.


title:
Recent Results from Decay-Angle Analyses of rho^0 Photoproduction at
  High Momentum Transfer from ZEUS

abstract:
  Recent results from decay-angle analyses of rho^0 photoproduction are
presented and discussed in the context of earlier measurements at lower energy
and lower momentum transfer.


title: A Polarized HERA Collider

abstract:
  A brief review is given of the status of nucleon spin structure functions as
determined from polarized deep inelastic lepton-nucleon scatttering, including
current outstanding problems. The characteristics of a polarized HERA collider,
some of the particle physics topics it could address, and the accelerator
physics challenges it must meet are discussed.


title: Development of a Straw Tube Chamber with Pickup-Pad Readout

abstract:
  We have developed a straw tube chamber with pickup-pad readout. The mechanism
for signal pickup, the size of the pickup signal, and the distribution of
signals among neighboring pads are discussed. We have tested a prototype
chamber in a beamtest at Brookhaven National laboratory and have measured
chamber efficiencies in excess of 99%.


title: Exclusive $\rho^{0}$ Production in Polarized DIS at SMC

abstract:
  Preliminary spin cross section asymmetries for exclusive $\rho^{0}$
lepto-production, $\vec{\mu} + \vec{N} \to \mu' + N + \rho^{0} (\rho^{0} \to
\pi^{+} \pi^{-})$, are reported. These asymmetries have been determined for the
first time by the Spin Muon Collaboration (SMC) at low Q^2 (photoproduction)
and at large Q^2 (DIS) for different $p_T^2$ intervals in the kinematic range
$0.01 <Q^2< 60 GeV^2$ and $140 < W^2 < 310 GeV^2$ (<W> \simeq 15 GeV) for the
full SMC data set. About 100 K $\rho^{0}$'s have been selected for $0.62 < m
(\pi^{+} \pi^{-}) < 1.07 GeV/c^2$ and $|I|< 0.05$. Within the statistical
precision, no significant asymmetries have been observed at low $Q^{2}$ in the
preliminary results.


title: The Ratio of Dimensionless Jet Cross Sections at the Tevatron

abstract:
  Several sources, both experimental and theoretical, subject inclusive jet
cross section measurements to large uncertainties. On the experimental side,
the energy scale contributes between 10% and 30% uncertainties. On the
theoretical side, choice of parton distribution function introduces a 20%
variation in the prediction; freedom in renormalization scale provides another
uncertainty of up to 30%. The ratio of inclusive jet cross sections reduces the
uncertainty from these major sources, permitting a very precise test of
next-to-leading order QCD. The preliminary results from D\O and CDF differ from
simple QCD predictions in normalization and differ from each other at small
values of jet $x_T$.


title: Parton energy loss limits and shadowing in Drell-Yan dimuon production

abstract:
  A precise measurement of the ratios of the Drell-Yan cross section per
nucleon for an 800 GeV/c proton beam incident on Be, Fe and W targets is
reported. The behavior of the Drell-Yan ratios at small target parton momentum
fraction is well described by an existing fit to the shadowing observed in
deep-inelastic scattering. The cross section ratios as a function of the
incident parton momentum fraction set tight limits on the energy loss of quarks
passing through a cold nucleus.


title:
Determination of neutrino incoming direction in the CHOOZ experiment and
  Supernova explosion location by scintillator detectors

abstract:
  The CHOOZ experiment measured the antineutrino flux at a distance of about 1
Km from two nuclear reactors in order to detect possible neutrino oscillations
with squared mass differences as low as 10**-3 eV**2 for full mixing. We show
that the data analysis of the electron antineutrino events, collected by our
liquid scintillation detector, locates the antineutrino source within a cone of
half-aperture of about 18 degrees at the 68% C.L.. We discuss the implications
of this experimental result for tracking down a supernova explosion.


title: Real and virtual photon structure from dijet events

abstract:
  Jet production in $ep$ collisions is sensitive to the partonic structure of
photon. The latest measurements of dijet production from the H1 experiment
provide new results of the gluon density of real photons at low $x$ and, for
the first time, on the partonic density of virtual photons. Properties of the
photon remnant were measured as a function of the hard scale defined by the
$p_T$ of the jets. The comparison of dijet cross sections with the NLO QCD
calculation shows the non-triviality of the concept of virtual photon
structure.


title: Evidence of New States Decaying into $\Xi_{c}^{*}\pi$

abstract:
  Using data recorded by the CLEO II detector at CESR, we report evidence for
two new charmed baryons, one decaying into $\Xi_c^+\pi^+\pi^-$ via an
intermediate $\Xi_c^{*0}$, and its isospin partner decaying into
$\Xi_c^0\pi^+\pi^-$ via an intermediate $\Xi_c^{*+}$. We measure the mass
differences of the two states to be $M(\Xi_c^+\pi^+\pi^-)-M(\Xi_c^+)=$
$348.6\pm0.6\pm1.0$ MeV, and $M(\Xi_c^0\pi^+\pi^-)-M(\Xi_c^0)=$
$347.2\pm0.7\pm2.0$ MeV. We interpret these new states as the $J^P = {3
\over{2}}^- $ $\Xi_{c1}$ particles, the charmed-strange analogues of the
$\Lambda_{c1}^+(2625)$.


title: Jet and hadron production in photon-photon collisions

abstract:
  Di-jet and inclusive charged hadron production cross-sections measured in
photon-photon collisions by OPAL are compared to NLO pQCD calculations. Jet
shapes measured in photon-photon scattering by OPAL, in deep-inelastic ep
scattering by H1 and in photon-proton scattering by ZEUS are shown to be
consistent in similar kinematic ranges. New results from TOPAZ on prompt photon
production in photon-photon interactions are presented.


title:
Limit on Tau Neutrino Mass from $\tau^{-}\to
  \pi^{-}\pi^{+}\pi^{-}\pi^{0}\nu_{\tau}$

abstract:
  From a data sample of 29058 $\tau^\pm\to\pi^\pm\pi^+\pi^-\pi^0\nu_\tau$
decays observed in the CLEO detector we derive a 95% confidence upper limit on
the tau neutrino mass of 28 MeV.


title: Recent Results from the Tevatron Fixed Target and Collider Experiments

abstract:
  We present a review of recent QCD related results from the Fermilab Tevatron
fixed target and collider experiments. Topics include jet and boson production,
W boson and top quark mass measurements, and studies of CP violation.


title: Performance of RPCs operated at the YangBaJing Laboratory

abstract:
  The ARGO-YBJ experiment will be installed at YangBaJing Cosmic Ray Laboratory
(Tibet, P.R. China), 4300 m a.s.l. . It consists of a full coverage of about
10^4 m^2 realized with RPC chambers.
  A small carpet of about 50 m^2 has been operated at YangBaJing in order to
check the RPC performance in these high altitude conditions.
  Results concerning efficiency and time resolution are reported.


title: Internal Jet Structure in Dijet Production in Deep-Inelastic Scattering

abstract:
  The internal jet structure in dijet production in deep-inelastic scattering
is measured with the H1 detector at HERA. Jets with transverse energies
E(T,breit) > 5 GeV are selected in the Breit frame employing kt and cone jet
algorithms in the kinematic region of squared momentum transfers of 10 < Q^2 <
120 GeV^2 and x-Bjorken values of 0.0002 < x < 0.008. Jet shapes and subjet
multiplicities are measured as functions of a resolution parameter. The
corrected data are well described by QCD models. It is observed that jets are
more collimated with increasing transverse jet energies and decreasing
pseudo-rapidities, i.e. towards the photon direction. Comparisons with OPAL
data show that jet shapes of jets measured in photon-photon collisions are very
similar to those measured in ep collisions.


title: Measurement of the Atmospheric Muon Neutrinos with the MACRO Detector

abstract:
  The flux of muons induced by atmospheric neutrinos has been measured with the
MACRO detector. Different event topologies have been detected, due to neutrino
interactions in the apparatus and in the rock below it. The upward-throughgoing
muon sample is the larger one and is generated by neutrinos with a peak energy
of ~100 GeV. The observed upward-throughgoing muons are 26 % fewer than
expected and the zenith angle distribution does not fit with the expected one.
Assuming \mutau neutrino oscillation, the angular shape and the normalization
factor suggest maximal mixing and \Delta m^2 of a few times 10^{-3} eV^2. Also
the other event categories induced by low-energy neutrinos (peak energy ~ 4
GeV) show a deficit of observed events. The value of this deficit and its
uniformity with respect to the angular bins are in agreement with the
oscillation parameters suggested by the analysis of the upward-throughgoing
muon sample.


title: Inclusive Jet Cross Sections in pbarp Collisions at 630 and 1800 GeV

abstract:
  We have made a precise measurement of the inclusive jet cross section at 1800
GeV. The result is based on an integrated luminosity of 92 pb**-1 collected at
the Fermilab Tevatron pbarp Collider with the DO detector. The measurement is
reported as a function of jet transverse energy (60 GeV < ET < 500 GeV), and in
the pseudorapidity intervals |eta|<0.5 and 0.1<eta<0.7. A preliminary
measurement of the pseudorapidity dependence of inclusive jet production
(eta<1.5) is also discussed. The results are in good agreement with predictions
from next-to-leading order (NLO) quantum chromodynamics (QCD). D\O has also
determined the ratio of jet cross sections at $\sqrt{s}$=630 GeV and
$\sqrt{s}$=1800 GeV ($|\eta|\leq 0.5$). This preliminary measurement differs
from NLO QCD predictions.


title:
Upper Limit on the Prompt Muon Flux Derived from the LVD Underground
  Experiment

abstract:
  We present the analysis of the muon events with all muon multiplicities
collected during 21804 hours of operation of the first LVD tower. The measured
depth-angular distribution of muon intensities has been used to obtain the
normalization factor, A, the power index, gamma, of the primary all-nucleon
spectrum and the ratio, R_c, of prompt muon flux to that of pi-mesons - the
main parameters which determine the spectrum of cosmic ray muons at the sea
level. The value of gamma = 2.77 +/- 0.05 (68% C.L.) and R_c < 2.0 x 10^-3 (95%
C.L.) have been obtained. The upper limit to the prompt muon flux favours the
models of charm production based on QGSM and the dual parton model.


title:
Search for flavor-changing neutral currents and lepton-family-number
  violation in two-body D0 decays

abstract:
  Results of a search for the three neutral charm decays, D0 -> mu e, D0 -> mu
mu, and D0 -> e e, are presented. This study was based on data collected in
Experiment 789 at the Fermi National Accelerator Laboratory using 800 GeV/c
proton-Au and proton-Be interactions. No evidence is found for any of the
decays. Upper limits on the branching ratios, at the 90% confidence level, are
obtained.


title: Recent Results on the Top Quark from the Tevatron Collider Experiments

abstract:
  This paper presents the latest measurements of the properties of the top
quark as determined by the DZero and CDF collaborations at the Fermilab
Tevatron ppbar collider. Both experiments have studied the all-hadronic decay
mode of ttbar events. The top quark measurement has been refined over the past
year, with the addition of new channels and a re-evaluation of some of the
earlier ones. There are recent studies of the mass of the ttbar system, the
helicity of the W bosons in the top quark decays, and of the correlation of the
spins of the top and antitop quarks. New results are also reported on searches
for charged Higgs bosons in top quark decay, and for electroweak production of
single top quarks.


title:
A Measurement of the Weak Mixing Angle in Neutrino-Nucleon Scattering at
  NuTeV

abstract:
  The NuTeV experiment at Fermilab presents a determination of the electroweak
mixing angle. High purity, large statistics samples of muon-neutrino and
muon-antineutrino events allow the use of the Paschos-Wolfenstein relation.
This considerably reduces systematic errors associated with charm production
and other sources. With Standard Model assumptions, this measurement of sin2thw
indirectly determines the W boson mass to a precision comparable to direct
measurements from high energy e+e- and p-pbar colliders. NuTeV measures
sin^2theta_W (on-shell) = 0.2253 +/- 0.0019(stat) +/- 0.0010(syst) which
implies M_W = 80.26 +/- 0.11 GeV.


title:
Extraction of the Width of the W Boson from Measurements of
  sigma(ppbar->W+X)B(W->e nu) and sigma(ppbar->Z+X)B(Z->e e) and their Ratio

abstract:
  We report on measurements of inclusive cross sections times branching
fractions into electrons for W and Z bosons produced in ppbar collisions at
sqrts=1.8 TeV.From an integrated luminosity of 84.5 inverse pb recorded in
1994--1995 using the D0 detector at the Fermilab Tevatron, we determine
sigma(ppbar->W+X)B(W->e nu) = 2310 +- 10(stat) +- 50(syst) +- 100(lum) pb and
sigma(ppbar->Z+X)B(Z->e e) = 221 +- 3(stat) +- 4(syst) +- 10(lum) pb. From
these, we derive their Ratio R = 10.43 +- 0.15(stat) +- 0.20(syst) +-
0.10(NLO), B(W->e nu) = 0.1066 +- 0.0015(stat) +- 0.0021(syst) +-
0.0011(theory)+- 0.0011(NLO), and Gamma_W = 2.130 +- 0.030(stat) +- 0.041(syst)
+- 0.022(theory) +- 0.021(NLO) GeV. We use the latter to set a 95% confidence
level upper limit on the partial decay width of the W boson into non-standard
model final states, Gamma_W^{inv}, of 0.168 GeV. Combining these results with
those from the 1992--1993 data gives R = 10.54 +- 0.24, Gamma_W = 2.107 +-
0.054 GeV, and a 95% C.L. upper limit on Gamma_W^{inv} of 0.132 GeV. Using a
sample with a luminosity of 505 inverse nb taken at sqrts=630 GeV, we measure
sigma(ppbar->W+X)B(W->e nu) = 658 +- 67 pb.


title: A Search for Disoriented Chiral Condensate at the Fermilab Tevatron

abstract:
  We present results from MiniMax (Fermilab T-864), a small test/experiment at
the Tevatron designed to search for the production of disoriented chiral
condensate (DCC) in $p - \bar p$ collisions at $\sqrt{s} = 1.8$ TeV in the
forward direction, $\sim 3.4 < \eta < \sim 4.2$. Data, consisting of $1.3
\times 10^6$ events, are analyzed using the robust observables developed in an
earlier paper. The results are consistent with generic, binomial-distribution
partition of pions into charged and neutral species. Limits on DCC production
in various models are presented.


title: Summary of the Structure Function Working Group at DIS'99

abstract:
  We summarize the experimental and theoretical results presented in the
``Structure Function Working Group - WG1'' at DIS'99.


title: Future Polarised DIS Fixed Target Experiments

abstract:
  New experiments in polarised deep inelastic scattering will mainly
concentrate on the measurement of semi-inclusive asymmetries. Especially, the
upgraded HERMES experiment at DESY and the newly build COMPASS experiment at
CERN will investigate the gluon polarisation via open charm and high p_T hadron
pair production, study in detail the flavour decomposition of the quark
helicity distributions and measure the tranversity distributions with
tranversely polarised targets.


title: Two Recent Results on B Physics from CDF

abstract:
  Preliminary results from two recent CDF b physics analysis are presented. The
first obtains sin(2beta) = 0.79 + 0.41 -0.44 from a measurement of the
asymmetry in B0, B0bar to J/psi K_short decays, providing the best direct
indication so far that CP invariance is violated in the b sector. The second
obtains new results on the parity even (A_0 and A_par) and odd (A_perp)
polarization amplitudes from full angular analyses of B0 to J/psi K*0 and B_s
to J/psi phi decays.


title: CKM Physics from B Decays using the CLEO Experiment

abstract:
  We report on studies of three types of B-meson decay that can contribute to
an understanding of fundamental intergenerational quark mixing,
charge-conjugation--parity violation, and long-distance quantum chromodynamics.
Specifically, we discuss a selection of analyses related to the
Cabibbo-Kobayashi-Maskawa (CKM) parameters Vcb, Vub, alpha, and gamma, and the
nonperturbative heavy quark effective theory quantities lambda_1 and
lambda_bar. We first describe an examination of the first and second moments of
the hadronic-recoil mass and charged-lepton energy spectra in inclusive b -> c
l nu decays. We also report on the reconstruction, using similar experimental
techniques, of the CKM-suppressed decay B -> rho l nu and the extraction of its
branching fraction, Br(B0 -> rho- l+ nu) = (2.57 +- 0.29 +0.33/-0.46 +- 0.41) x
10E-4, as well as the value |Vub| = (3.25 +- 0.14 +0.21/-0.29 +- 0.55) x 10E-3,
where the uncertainties are statistical, systematic, and due to model
dependence, respectively. Finally, we present results on rare two-body
charmless hadronic B -> K pi, pi pi, and K K decays and comment briefly on
their implications to the geometry of the CKM unitarity triangle, including a
bound on gamma.


title: QCD at LEP 2 and WW Final State Interactions

abstract:
  A short overview of the QCD program at LEP~2 is given. Studies of final state
interactions in e+e- -> WW -> qqqq decays are discussed.


title:
Measurement of the $\phi$ meson parameters with CMD-2 detector at
  VEPP-2M Collider

abstract:
  About 300 000 $e^+e^-\to \phi\to K^0_L K^0_S$ events in the center of mass
energy range from 984 to 1040 MeV were used for the measurement of the $\phi$
meson parameters. The following results have been obtained: $\sigma_0 = (1367
\pm 15 \pm 21) nb, m_{\phi}=(1019.504 \pm 0.011 \pm 0.033) MeV/c^2,
\Gamma_\phi=(4.477 \pm 0.036 \pm 0.022) MeV, \Gamma_{e^+e^-}\cdot B(\phi\to
K^0_L K^0_S) = (4.364 \pm 0.048 \pm 0.065)\cdot 10^{-4}$ MeV.


title:
Tests of Power Corrections to Event Shape Distributions from e+e-
  Annihilation

abstract:
  A study of differential event shape distributions using e+e- data at
centre-of-mass energies of 35 to 183 GeV is presented. We investigated
non-perturbative power corrections for the thrust, C-parameter, total and wide
jet broadening observables. We observe a good description of the distributions
by the combined resummed QCD calculations plus power corrections from the
dispersive approach. The single non-perturbative parameter \alpha_0 is measured
to be \alpha_0 (2 GeV) = 0.502 +- 0.013 (stat.) ^{+0.046)_{-0.032} (exp. syst.)
^{+0.074}_{-0.053} (theo. syst.) and is found to be universal for the
observables studied within the given systematic uncertainties. Using revised
calculations of the power corrections for the jet broadening variables,
improved consistency of the individual fit results is obtained. Agreement is
also found with results extracted from the mean values of event shape
distributions.


title:
Total Forward and Differential Cross Sections of Neutral D Mesons
  Produced in 500 GeV/c $\pi^-$-Nucleon Interactions

abstract:
  We measure the neutral D total forward cross section and the differential
cross sections as function of Feynman-x ($x_F$) and transverse momentum squared
for 500 GeV/c $\pi^-$-nucleon interactions. The results are obtained from
88990+-460 reconstructed neutral D mesons from Fermilab experiment E791 using
the decay channels $D\to K^-\pi^+$ and $D\to K^-\pi^+\pi^-\pi^+$ (and charge
conjugates). We extract fit parameters from the differential cross sections and
provide the first direct measurement of the turnover point in the $x_F$
distribution, 0.0131+-0.0038. We measure an absolute $D^0 + \bar{D^0}$ ($x_F >
0$) cross section of 15.4+1.8-2.3 microbarns/nucleon (assuming a linear A
dependence). The differential and total forward cross sections are compared to
theoretical predictions and to results of previous experiments.


title:
Flavor Decomposition of the Polarized Quark Distributions in the Nucleon
  from Inclusive and Semi-inclusive Deep-inelastic Scattering

abstract:
  Spin asymmetries of semi-inclusive cross sections for the production of
positively and negatively charged hadrons have been measured in deep-inelastic
scattering of polarized positrons on polarized hydrogen and 3He targets, in the
kinematic range 0.023<x<0.6 and 1 GeV^2<Q^2<10 GeV^2. Polarized quark
distributions are extracted as a function of x for up $(u+u_bar) and down
(d+d_bar) flavors. The up quark polarization is positive and the down quark
polarization is negative in the measured range. The polarization of the sea is
compatible with zero. The first moments of the polarized quark distributions
are presented. The isospin non-singlet combination Delta_q_3 is consistent with
the prediction based on the Bjorken sum rule. The moments of the polarized
quark distributions are compared to predictions based on SU(3)_f flavor
symmetry and to a prediction from lattice QCD.


title: W mass measurement at LEP

abstract:
  In 1998, the four experiments of LEP, i.e. ALEPH, DELPHI, L3 and OPAL,
collected data of about 175 /pb per experiment at the center-of-mass energy of
189 GeV. Using these data, the mass of W boson was directly measured by
reconstructing the decay products of two W bosons from the e+e- collisions. The
W mass measurement was combined personally with the results obtained from data
at 161, 172, and 183 GeV. This yielded the private LEP2 average of Mw = 80.350
+/- 0.056 GeV.


title: Charm Production at NuTeV

abstract:
  Neutrino deep-inelastic scattering provides a means to study both the strange
and charm content of the nucleon. The NuTeV experiment (Fermilab E-8Neutrino
deep-inelastic scattering provides a means to study both the strange and charm
content of the nucleon. The NuTeV experiment (Fermilab E-815) takes full
advantage of separated neutrino and anti-neutrino beams to probe the nucleon.
The strange sea is studied with charged-current charm production resulting in
an opposite-signed two muon final state. The charm content of the nucleon is
probed via neutral-current charm production creating an event with a single
wrong-signed muon. Preliminary results are presented for both analyses.


title: Strange Content of the Nucleon (NuTeV)

abstract:
  The NuTeV experiment uses neutrino deep-inelastic scattering from separate
neutrino and anti-neutrino beams to study the structure of the nucleon.
Charged-current production of charm is sensitive to the strange content of the
nucleon while neutral-current charm production probes the charm content.
Preliminary analyses of both topics are presented along with discussion of
possible momentum asymmetry in the strange sea.


title: Total Hadronic Cross-Section of Photon-Photon Interactions at LEP

abstract:
  The total hadronic cross-section sigma_gg(W) for the interaction of real
photons, gg->hadrons, is measured for gg centre-of-mass energies 10<W<110 GeV.
The cross-section is extracted from a measurement of the process e+e- ->
e+e-g*g* -> e+e- hardrons, using a luminosity function for the photon flux
together with form factors for extrapolating to real photons (Q^2=0 GeV^2). The
data were taken with the OPAL detector at LEP at e+e- centre-of-mass energies
161, 172 and 183 GeV. The cross-section sigma_gg(W) is compared with Regge
factorisation and with the energy dependence observed in gp and pp
interactions. The data are also compared to models which predict a faster rise
of sigma_gg(W) compared to gp and pp interactions due to additional hard gg
interactions not present in hadronic collisions.


title: Inclusive hard processes in photon-photon and photon-proton interactions

abstract:
  Measurements of jet, prompt photon, high-pT hadron and heavy quark production
in photon-induced processes provide tests of QCD and are sensitive to the
photon parton densities. A review of the latest experimental results in
photon-photon and photon-proton interactions is presented.
Next-to-leading-order QCD calculations for these measurements are discussed.


title:
Measurements of inclusive semileptonic branching fractions of b hadrons
  in Z decays

abstract:
  A measurement of inclusive semileptonic branching fractions of b hadrons
produced in Z decays is presented. An enriched Z -> bbbar sample is obtained
with a lifetime flavour-tagging technique. The leptonic events are then
selected from this sample, and classified according to their origin, which is
determined by comparing the distribution of several kinematic variables using
artificial neural network techniques. Using 3.6 million multihadronic events
collected with the OPAL detector at energies near the Z resonance, the values
BR(b->lX) =(10.83 +- 0.10(stat.) +- 0.20(syst.) +0.20 -0.13(model)) %
BR(b->c->lX) = (8.40 +- 0.16(stat.) +- 0.21(syst.) +0.33 -0.29 (model)) % are
measured, where b denotes all weakly decaying b hadrons and l represents either
e or mu. The second error includes all experimental systematic uncertainties
whereas the last error is due to uncertainties in modelling of the lepton
momentum spectrum in semileptonic decays and b quark fragmentation. The average
fraction of the beam energy carried by the weakly decaying b hadron, xe, is
measured to be <xe> = 0.709 +- 0.003(stat.) +- 0.003 (syst.) +- 0.013(model)
where the modelling error is dominated by the choice of b fragmentation model.
The agreement between data and various semileptonic decay models and
fragmentation functions is also investigated.


title: A Measurement of xF_3(nu)-xF_3(anti-nu) and R with the CCFR Detector

abstract:
  We report on a measurement of the neutrino-nucleon and antineutrino-nucleon
differential cross sections in the CCFR detector. The measurement of the
differential cross sections over a wide range of energies allows Delta xF_3 =
xF_3(nu)-xF_3(anti-nu) and R to be extracted. Delta xF_3 is related to the
difference between the contributions of the strange and charm seas in the
nucleon to production of massive charm quark. The results for Delta xF_3 are
compared to various massive charm NLO QCD models. The Q^2 dependence of R for
x<0.1 has been measured for the first time.


title:
A Study of Spin Alignment of rho(770)+- and omega(782) Mesons in
  Hadronic Z Decays

abstract:
  The helicity density matrix elements rho[00] of rho(770)+- and omega(782)
mesons produced in Z decays have been measured using the OPAL detector at LEP.
Over the measured meson energy range, the values are compatible with 1/3,
corresponding to a statistical mix of helicity -1, 0 and +1 states. For the
highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00]
values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114,
respectively. These results are compared to measurements of other vector
mesons.


title: Detection of low energy solar neutrinos with HPGermanium

abstract:
  The potential of the GENIUS proposal to measure the spectrum of low energy
solar neutrinos in real time is studied. The detection reaction is elastic
neutrino-electron scattering. The energy resolution for detecting the recoil
electrons is about 0.3 %, the energy threshold is a few keV. The expected
number of events for a target of one ton of natural germanium is 3.6 events/day
for pp-neutrinos and 1.3 events/day for 7Be-neutrinos, calculated in the
standard solar model (BP98). It should be feasible to achieve a background low
enough to measure the low energy solar neutrino spectrum.


title:
Search for Rare and Forbidden Dilepton Decays of the D+, Ds, and D0
  Charmed Mesons

abstract:
  We report the results of a search for flavor-changing neutral current,
lepton-flavor violating, and lepton-number violating decays of D+, Ds, and D0
mesons (and their antiparticles) into modes containing muons and electrons.
Using data from Fermilab charm hadroproduction experiment E791, we examine the
pi,l,l and K,l,l decay modes of D+ and Ds and the l+l- decay modes of D0. No
evidence for any of these decays is found. Therefore, we present
branching-fraction upper limits at 90% confidence level for the 24 decay modes
examined. Eight of these modes have no previously reported limits, and fourteen
are reported with significant improvements over previously published results.


title: Heavy quark asymmetries with DELPHI

abstract:
  The measurements of the forward-backward asymmetry in Z -> c cbar and Z -> b
bbar decays are among the most precise determinations of sin^2(theta)_W. In
this paper the results obtained by the DELPHI experiment at LEP with three
different analyses are reviewed together with the impact of the combined LEP
result on the global Electroweak fit.


title:
A Search for Leptoquark Bosons and Lepton Flavor Violation in
  Positron-Proton Collisions at HERA

abstract:
  A search for new bosons possessing couplings to lepton-quark pairs is
performed in the H1 experiment at HERA using 1994 to 1997 data corresponding to
an integrated luminosity of 37pb^-1. First generation leptoquarks (LQs) are
searched in very high Q^2 neutral (NC) and charged (CC) current data samples.
The measurements are compared to Standard Model (SM) expectations from
deep-inelastic scattering (DIS). A deviation in the Q^2 spectrum previously
observed in the 1994 to 1996 dataset at Q^2 \gsim 15000GeV^2 remains, though
with less significance. This deviation corresponded to a clustering in the
invariant mass spectrum at M \simeq 200 GeV which is not observed with the 1997
dataset alone. The NC DIS data is used to constrain the Yukawa couplings lambda
of first generation scalar and vector LQs in the Buchmueller-Rueckl-Wyler
effective model. Scalar LQs are excluded for masses up to 275GeV for a coupling
of electromagnetic strength, lambda=0.3. A sensitivity to coupling values \lsim
1 is established for masses up to 400GeV for any LQ type. The NC and CC DIS
data are combined to constrain lambda for arbitrary branching ratios of the LQ
into eq in a generic model. For a decay branching ratio into e^+ u pairs as
small as 10%, LQ masses up to 260 GeV are ruled out for lambda=0.3. LQs
possessing couplings to mixed fermion generations, which could lead to signals
of lepton flavor violation (LFV), are searched in events with a high transverse
momentum mu or tau. No mu+X or tau+X event candidate is found that is
compatible with LQ kinematics. Constraints are set on the Yukawa coupling
involving the mu and tau lepton in a yet unexplored mass range.


title: Study of the radiative decay $\phi \to \eta \gamma$ with CMD-2 detector

abstract:
  Using the $1.9 pb^{-1}$ of data collected with the CMD-2 detector at VEPP-2M
the decay mode $\phi \to \eta \gamma$, $\eta \to \pi^+\pi^-\pi^0$ has been
studied. The obtained branching ratio is B($\phi \to \eta \gamma) = (1.18 \pm
0.03 \pm 0.06) %$.


title: Upper limit on the Ks ---> 3 pi0 decay

abstract:
  The search for CP-violating K_S\to3\pi^0 decay was performed with SND
detector at VEPP-2M e^+e^- collider. The total amount of data corresponding to
7 million produced K_S mesons was analyzed. No candidate events were found,
giving an upper limit of the decay branching ratio: Br(K_S\to3\pi^0) <
1.4\cdot10^{-5} at 90% confidence level.


title: First observation of the $\phi\to\pi^+\pi^-\gamma$ decay

abstract:
  Radiative decays of the $\phi$ meson have been studied using a data sample of
about 20 million $\phi$ decays collected by the CMD-2 detector at VEPP-2M
collider in Novosibirsk. From selected $e^+e^-\to\pi^{+}\pi^{-}\gamma$ events
the $\phi\to\pi^{+}\pi^{-}\gamma$ decay has been observed for the first time.
\par Under the assumption that the intermediate $f_{0}(980)\gamma$ state
dominates in the $\phi \to \pi^+\pi^-\gamma$ decay, the corresponding branching
ratio is $Br(\phi\to f_{0}(980)\gamma)=(1.93\pm 0.46\pm 0.50)\times10^{-4}$.
\par Selected $e^+e^-\to\mu^+\mu^-\gamma$ events were used to obtain
$Br(\phi\to\mu^+\mu^-\gamma) =(1.43\pm 0.45\pm 0.14)\times10^{-5}$ for
$E_{\gamma}>20$ MeV. \par Using the same data sample, upper limits at 90% CL
have been obtained for the C-violating decay of the $\phi$:
  $Br(\phi\to\rho\gamma) < 1.2\times10^{-5}$; and for the P- and CP-violating
decay of the $\eta$: \par $Br(\eta\to\pi^+\pi^-) < 3.3\times10^{-4}$.


title:
Study of the $\phi$ decays into $\pi^0\pi^0\gamma$ and $\eta\pi^0\gamma$
  final states

abstract:
  Radiative decays of the $\phi$ meson have been studied using a data sample of
about 19 million $\phi$ decays collected by the CMD-2 detector at VEPP-2M
collider in Novosibirsk. From selected $e^+e^-\to\pi^{0}\pi^{0}\gamma$ and
$e^+e^-\to\eta\pi^{0}\gamma$ events the following model independent results
have been obtained: \par $Br(\phi\to\pi^{0}\pi^{0}\gamma) = (0.92\pm
0.08\pm0.06)\times10^{-4}$ for $M_{\pi^{0}\pi^{0}}>700$ MeV, \par
$Br(\phi\to\eta\pi^{0}\gamma) = (0.90\pm 0.24\pm 0.10)\times10^{-4}$.
  It is shown that the intermediate mechanism $f_{0}(980)\gamma$ dominates in
the $\phi\to\pi^{0}\pi^{0}\gamma$ decay and the corresponding branching ratio
is \par $Br(\phi\to f_{0}(980)\gamma)=(2.90\pm 0.21\pm1.54)\times10^{-4}$. The
systematic error is dominated by the possible model uncertainty. \par Using the
same data sample the upper limit has been obtained for the P- and CP-violating
decay of $\eta$ at 90% CL: \par $Br(\eta\to\pi^{0}\pi^{0}) < 4.3\times10^{-4}$
>.


title: Experimental search for the decay mode K_L -> pi^0 gamma e^+ e^-

abstract:
  We report on results of a search for the decay mode K_L -> pi^0 gamma e^+ e^-
conducted by the E162 experiment at KEK. We observed no events and set a 90%
confidence level upper limit of Br(K_L -> pi^0 gamma e^+ e^-)< 7.1x10^{-7} for
its branching ratio. This is the first published experimental result on this
decay mode.


title:
Experimental investigation of changes in beta-decay count rate of
  radioactive elements

abstract:
  The experimental data on continuous investigation of changes in beta-decay
count rate of Cs-137 and Co-60 from 9.12.98 till 30.04.99, are presented. The
27-day and 24-hour periods in these changes, inexplicable by traditional
physics, have been found.


title:
Measurement of the inclusive differential cross section for Z bosons as
  a function of transverse momentum in pbarp collisions at sqrt{s}=1.8 TeV

abstract:
  We present a measurement of the differential cross section as a function of
transverse momentum of the Z boson 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 the NNLO resummation
prediction and extract values of the non-perturbative parameters for the
resummed prediction from a fit to the differential cross section.


title:
Measurement of High-Q^2 Charged-Current e^+p Deep Inelastic Scattering
  Cross Sections at HERA

abstract:
  The e^+p charged-current deep inelastic scattering cross sections,
$d\sigma/dQ^2$ for Q^2 between 200 and 60000 GeV^2, and $d\sigma/dx$ and
$d\sigma/dy$ for Q^2 > 200 GeV^2, have been measured with the ZEUS detector at
HERA. A data sample of 47.7 pb^-1, collected at a center-of-mass energy of 300
GeV, has been used. The cross section $d\sigma/dQ^2$ falls by a factor of about
50000 as Q^2 increases from 280 to 30000 GeV^2. The double differential cross
section $d^2\sigma/dxdQ^2$ has also been measured. A comparison between the
data and Standard Model (SM) predictions shows that contributions from
antiquarks ($\bar{u}$ and $\bar{c}$) and quarks (d and s) are both required by
the data. The predictions of the SM give a good description of the full body of
the data presented here. A comparison of the charged-current cross section
$d\sigma/dQ^2$ with the recent ZEUS results for neutral-current scattering
shows that the weak and electromagnetic forces have similar strengths for Q^2
above $M^2_W, M^2_Z$. A fit to the data for $d\sigma/dQ^2$ with the Fermi
constant $G_F$ and $M_W$ as free parameters yields $G_F = (1.171 \pm 0.034
(stat.) ^{+0.026}_{-0.032} (syst.) ^{+0.016}_{-0.015} (PDF)) \times 10^{-5}
GeV^{-2}$ and $M_W = 80.8 ^{+4.9}_{-4.5} (stat.) ^{+5.0}_{-4.3} (syst.)
^{+1.4}_{-1.3} (PDF) GeV$. Results for $M_W$, where the propagator effect alone
or the SM constraint between $G_F$ and $M_W$ have been considered, are also
presented.


title:
Progress and Problems in QCD - Report from the Hadronic Final States
  Working Group at DIS99

abstract:
  We present a summary of the Hadronic Final States parallel sessions of the
DIS99 Workshop. Topics were presented over two days and included both
theoretical and experimental talks. Recent progress in the understanding of QCD
in deep inelastic scattering, e^+e^- collisions, and in gamma and p collisions
was discussed.


title: The Structure of Quasi-Real and Virtual Photons

abstract:
  This review covers the measurements of the QED and QCD structure of
quasi-real and virtual photons from the reaction ee --> ee gamma* gamma(*) -->
ee X.


title: Measurement of the 1s-2s energy interval in muonium

abstract:
  The 1s-2s interval has been measured in the muonium ({$\mu^+e^-$}) atom by
Doppler-free two-photon laser spectroscopy. The frequency separation of the
states was determined to be 2 455 528 941.0(9.8) MHz in good agreement with
quantum electrodynamics. The muon-electron mass ratio can be extracted and is
found to be 206.768 38(17). The result may be interpreted as measurement of the
muon-electron charge ratio as $-1- 1.1(2.1)\cdot 10^{-9}$.


title: Search for the Decay K_L -> pi^0 nu nubar using pi^0 -> e^+ e^- gamma

abstract:
  We report on a search for the decay K_L -> pi^0 nu nubar, carried out as a
part of E799-II, a rare K_L decay experiment at Fermilab. Within the Standard
Model, the K_L -> pi^0 nu nubar decay is dominated by direct CP violating
processes, and thus an observation of the decay implies confirmation of direct
CP violation. Due to theoretically clean calculations, a measurement of B(K_L
-> pi^0 nu nubar) is one of the best ways to determine the CKM parameter eta.
No events were observed, and we set an upper limit B(K_L -> pi^0 nu nubar) <
5.9 times 10^-7 at the 90% confidence level.


title:
New results on the numu-nutau and nue-nutau oscillation search with the
  CHORUS detector

abstract:
  The present results on the $\numtonut$ oscillation search by the CHORUS
experiment at CERN are summarized. A fraction of the neutrino interactions
collected in 1994-1997 has been analysed, searching for $\nu_{\tau}$ charged
current interactions followed by the $\tau$ lepton decay into a negative
hadron, electron, or into a muon. A sample of 126,229 events with an identified
muon in the final state and 19,436 events without an identified muon in the
final state have been located in the emulsion target. Within the applied cuts,
no $\nu_{\tau}$ candidate has been found. This result leads to a 90% C.L. limit
$P(\numtonut)< 4.0\cdot 10^{-4}$ on the mixing probability. A $\nuetonut$
exclusion plot is also presented corresponding to 90% C.L. limit on the mixing
probability of $P(\nuetonut)<~3.0\cdot~10^{-2}$.


title: Double-tag events study with the L3 detector at sqrt(s)=189 GeV

abstract:
  A preliminary study of double tag events using the L3 detector at center of
mass energy sqrt{s}=189 GeV has been performed. The cross-section of gamma*
gamma* collisions is measured at average <Q2>=14.5 GeV2. The results are in
agreement with predictions based on perturbative QCD, while the Quark Parton
Model alone is insufficient to describe the data. The measurements lie below
the LO and above the NLO BFKL calculations.


title:
PeP-neutrino Detection by Lithium Detector as a Direct Way to Search for
  Oscillation of Solar Neutrinos

abstract:
  The high sensitivity of lithium detector to pep- and Be7-neutrinos makes a
lithium radiochemical detector a powerful tool for the search of the
oscillations of solar neutrinos. The first phase of lithium experiment on the
installation with 10 tons of metallic lithium will enable to collect data
within 1 year of measurements to provide very definite information about SMA
MSW solution. the second phase with 10 modules 10 tons each will measure the
semiannual variations of the signal, thus the contributions of pep- and
Be7-lines will be weighted, what will give a "smoking-gun" evidence about
"just-so" solution for large mixing angles and delta-m2 about 10-10 - 10-9 eV2.
If both regions are not confirmed the results of lithium detector can be
interpreted in favor of LMA MSW solution.


title: A Study of the LEP and SLD Measurements of $A_b$

abstract:
  A systematic study is made of the data dependence of the parameter
$A_{\rm{b}}$, that, since 1995, has shown a deviation from the Standard Model
prediction of between 2.4 and 3.1 standard deviations. Issues addressed
include: the effect of particular measurements, values found by individual
experiments, LEP/SLD comparison, and the treatment of systematic errors. The
effect, currently at the 2.4$\sigma$ level, is found to vary in the range from
1.7$\sigma$ to 2.9$\sigma$ by excluding marginal or particularly sensitive
data. Since essentially the full LEP and SLD Z decay data sets are now analysed
the meaning of the deviation, (new physics, or marginal statistical
fluctuation) is unlikely to be given by the present generation of colliders.


title: Search for R-parity Violating Supersymmetry in the Dielectron Channel

abstract:
  We report on a search for R-parity violating supersymmetry in p-pbar
collisions at sqrt(s) = 1.8 TeV using the D0 detector at Fermilab. Events with
at least two electrons and four or more jets were studied. We observe 2 events
in 99 +- 4.4 pb-1 of data, consistent with the expected background of 1.8 +-
0.4 events. This result is interpreted within the framework of minimal
low-energy supergravity supersymmetry models. Squarks with mass below 243
GeV/c^2 and gluinos with mass below 227 GeV/c^2 are excluded at the 95%
confidence level (C. L.) for A_0=0, mu < 0$, tan beta=2 and a finite value for
R-parity violating Yukawa coupling lambda'_1jk (j=1, 2 and k=1, 2, 3). For
equal squark and gluino masses, the corresponding mass limit is 277 GeV/c^2.


title:
Measurement of the Spin Asymmetry in the Photoproduction of Pairs of
  High-pT Hadrons at HERMES

abstract:
  We present a measurement of the longitudinal spin asymmetry A_|| in
photoproduction of pairs of hadrons with high transverse momentum p_T. Data
were accumulated by the HERMES experiment using a 27.5 GeV polarized positron
beam and a polarized hydrogen target internal to the HERA storage ring. For
h+h- pairs with p_T^h_1 > 1.5 GeV/c and p_T^h_2 > 1.0 GeV/c, the measured
asymmetry is A_|| = -0.28 +/- 0.12 (stat.) +/- 0.02 (syst.). This negative
value is in contrast to the positive asymmetries typically measured in deep
inelastic scattering from protons, and is interpreted to arise from a positive
gluon polarization.


title: Production of xi resonances in sigma induced reactions at 345 GeV/c

abstract:
  We report on a measurement of the differential and total cross sections of
inclusive production of Xi resonances in Sigma - nucleus collisions at 345
GeV/c.


title:
Measurement of the Angular Distribution of Electrons from W to e nu
  Decays Observed in ppbar Collisions at sqrt(s) = 1.8 TeV

abstract:
  We present a preliminary measurement of the electron angular distribution
parameter alpha2 in W to e nu events using data collected by the D0 detector
during the 1994--1995 Tevatron run. We compare our results with next-to-leading
order perturbative QCD, which predicts an angular distribution of 1 +/- alpha1
cos theta* +alpha_2 cos^2 theta*, where theta* is the angle between the charged
lepton and the antiproton in the Collins-Soper frame. In the presence of QCD
corrections, the parameters alpha1 and alpha2 become functions of pT(W), the W
boson transverse momentum. We present the first measurement of alpha_2 as a
function of pT(W). This measurement is of importance, because it provides a
test of next-to-leading order QCD corrections which are a non-negligible
contribution to the W mass measurement.


title:
W Production and the Search for Events with an Isolated High-Energy
  Lepton and Missing Transverse Momentum at HERA

abstract:
  A search for the leptonic decays of W bosons produced in the reaction e^+
p\to e^+ W^\pm X at a centre-of-mass energy of 300 GeV has been performed with
the ZEUS detector at HERA using an integrated luminosity of 47.7 pb^-1 . Three
events consistent with W\to e\nu decay are found, giving a cross section of 0.9
+1.0 -0.7 \pm 0.2 pb, in good agreement with the Standard Model prediction. The
corresponding 95% C.L. upper limit on the cross section is 3.3 pb. A search for
the decay W\to \mu\nu has a smaller selection efficiency and yields no
candidate events. Limits on the cross section for W production with large
hadronic transverse momentum have been obtained. A search for
high-transverse-momentum isolated tracks in events with large missing
transverse momentum yields results in good agreement with Standard Model
expectations, in contrast to a recent report by the H1 collaboration of the
observation of an excess of such events.


title:
Measurement of neutrino oscillations by means of a high density detector
  on the atmospheric neutrino beam

abstract:
  A high-density calorimeter, consisting of magnetized iron planes interleaved
by RPCs, as tracking and timing devices, is a good candidate for a next
generation experiment on atmospheric neutrinos. With 34 kt of mass and in four
years of data taking, this experiment will be sensitive to $\nu_\mu \to \nu_x$
oscillation with $\Delta m^2 > 6 \times 10^{-5}$ and mixing near to maximal and
fully cover the region of oscillation parameters suggested by Super-Kamiokande
results. Moreover, the experimental method will enable to measure the
oscillation parameters from the modulation of the L/E spectrum ($\nu_\mu$
disappearance). For $\Delta m^2 > 3 \times 10^{-3}$ eV$^2$, this experiment can
also establish whether the oscillation occurs into a tau or a sterile neutrino,
by looking for an excess of muon-less events at high energies produced by
upward-going tau neutrinos ($\nu_\tau$ appearance).


title:
Search for Exotic Baryons with Hidden Strangeness in the Experiments of
  the Sphinx Collaboration in Diffractive and Coulomb Production Processes

abstract:
  Experimental results of the SPHINX Collaboration on studying proton
diffractive production processes are presented. Evidences for new baryon states
with masses >1.8 GeV were obtained in hyperon-kaon effective mass spectra in
several reactions. New data for the diffractive reaction p+N->[Sigma0 K+]+N at
Ep=70 GeV were obtained with partially upgraded SPHINX setup. The data are in a
good agreement with the results of our previous study of this reaction. In the
mass spectrum M(Sigma0 K+) a structure at the threshold region with a mass
about 1800 MeV and a distinct X(2000) peak with M=1989+/-6 MeV and
Gamma=91+/-20 MeV are observed. Unusual features of the massive X(2000) state
(narrow decay width, anomalously large branching ratio for the decay channel
with strange particle emission) make it a serious candidate for a cryptoexotic
pentaquark baryon with hidden strangeness |qqqs sbar>. We also present new
results on the narrow threshold structure X(1810) with M=1807+/-7 MeV and
Gamma=62+/-19 MeV which is produced in the region of very small pt**2<0.01
GeV**2. The possibility of the Coulomb production mechanism for X(1810) is
discussed.


title:
Investigation of the $e^+e^- \to \omega \pi^0 \to \pi^0 \pi^0 \gamma$
  reaction in the energy domain near the $\phi$-meson

abstract:
  The $e^+e^- \to \omega \pi^0 \to \pi^0 \pi^0 \gamma$ process was investigated
in the SND experiment at the VEPP-2M collider. A narrow energy interval near
the $\phi$-meson was scanned. The observed cross-section reveals, at the level
of three standard deviation, the interference effect caused by $\phi \to
\pi^0\pi^0\gamma$ decay. The cross-section parameters, as well as the real and
imaginary parts of the $\phi$-meson related amplitude, were measured.


title:
Measurements of Transverse Energy Flow in Deep-Inelastic Scattering at
  HERA

abstract:
  Measurements of transverse energy flow are presented for neutral current
deep-inelastic scattering events produced in positron-proton collisions at
HERA. The kinematic range covers squared momentum transfers Q^2 from 3.2 to
2,200 GeV^2, the Bjorken scaling variable x from 8.10^{-5} to 0.11 and the
hadronic mass W from 66 to 233 GeV. The transverse energy flow is measured in
the hadronic centre of mass frame and is studied as a function of Q^2, x, W and
pseudorapidity. A comparison is made with QCD based models. The behaviour of
the mean transverse energy in the central pseudorapidity region and an interval
corresponding to the photon fragmentation region are analysed as a function of
Q^2 and W.


title: A New measurement of the W boson mass at D0

abstract:
  We present a new measurement of the $W$ mass using the $W\to e\nu$ data from
the D\O forward detectors at the Fermilab Tevatron $p \bar p$ Collider. This is
the first measurement of the $W$ mass with electron candidates in the range
$1.5 < \mid \eta \mid < 2.5$. We present measurements of the $W$ mass using the
transverse mass, the electron transverse momentum and the neutrino transverse
momentum, and the combined result using all three techniques. The combination
of the forward detector measurement with the previous measurements using the
central detector gives a new precise measurement of the $W$ mass from D\O.


title:
Small Angle Muon and Bottom Quark Production in pbarp Collisions at
  sqrt(s) = 1.8 TeV

abstract:
  This Letter describes a measurement of the muon cross section originating
from b quark decay in the forward rapidity range 2.4 < y(mu) < 3.2 in pbarp
collisions at sqrt(s) = 1.8 TeV. The data used in this analysis were collected
by the D0 experiment at the Fermilab Tevatron. We find that NLO QCD
calculations underestimate b quark production by a factor of four in the
forward rapidity region. A cross section measurement using muon+jet data has
been included in this version of the paper.


title: Forward Pi0-Meson Production at HERA

abstract:
  High transverse momentum pi0-mesons have been measured with the H1 detector
at HERA in deep-inelastic ep scattering events at low Bjorken-x, down to x <~
4.10^{-5}. The measurement is performed in a region of small angles with
respect to the proton remnant in the laboratory frame of reference, namely the
forward region, and corresponds to central rapidity in the centre of mass
system of the virtual photon and proton. This region is expected to be
particularly sensitive to QCD effects in hadronic final states. Differential
cross-sections for inclusive pi0-meson production are presented as a function
of Bjorken-x and the four-momentum transfer Q^2, and as a function of
transverse momentum and pseudorapidity. A recent numerical BFKL calculation and
predictions from QCD models based on DGLAP parton evolution are compared with
the data.


title:
An All-Solid State Central Tracker for the Proposed DESY
  Electron-Positron Linear Collider

abstract:
  This report describes an all-solid state central tracker which is intended
for use in a detector at the proposed DESY 500 GeV electron-positron linear
collider or a similar accelerator. The precise position measurements from
position-sensitive silicon detectors give the tracker an outstanding momentum
resolution for high momentum tracks: sigma_p/p^2 = 3.6 x 10^{-5} (GeV/c)^{-1}
for tracks perpendicular to the beam-line. The report concludes with an example
layout for a detector which uses this central tracker.


title: Momentum Resolution Studies for a large TPC-Based Central Tracker

abstract:
  This note describes a study on the momentum resolution of the TPC-based
central tracker design which will be included in the ECFA/DESY conceptual
design report (CDR) for the proposed DESY 500 GeV electron-positron linear
collider. The study found it to be likely that the central tracker could
achieve a momentum resolution of approximately 10^{-4} (GeV/c)^{-1},
particularly if a layer of silicon microstrip detectors were to be added just
inside the TPC.


title: Neutrino Physics at a Muon Collider

abstract:
  An overview is given of the neutrino physics potential of future muon storage
rings that use muon collider technology to produce, accelerate and store large
currents of muons.


title:
Estimates of Vertex Tagging Efficiencies at a Muon Collider Higgs
  Factory

abstract:
  Tagging efficiencies and purities are estimated for the decay modes H ->
b-bbar, H -> tau-taubar and H -> c-cbar of Higgs bosons produced at an
s-channel muon collider Higgs factory.


title: Neutrino Physics at Muon Colliders


title: Issues on NLO pQCD Programs

abstract:
  This paper summarizes a talk presented at the Durham HERA '98 Workshop. We
compare the features that are available in NLO pQCD programs and demonstrate
that understanding where in phase space NLO calculations are accurate is vital
for extracting information from measurements at the HERA experiments.


title: Limits on Neutrino Oscillations from the CHOOZ Experiment

abstract:
  We present new results based on the entire CHOOZ data sample. We find (at 90%
confidence level) no evidence for neutrino oscillations in the anti_nue
disappearance mode, for the parameter region given by approximately Delta m**2
> 7 x 10**-4 eV^2 for maximum mixing, and sin**2(2 theta) = 0.10 for large
Delta m**2. Lower sensitivity results, based only on the comparison of the
positron spectra from the two different-distance nuclear reactors, are also
presented; these are independent of the absolute normalization of the anti_nue
flux, the cross section, the number of target protons and the detector
efficiencies.


title: Medium energy calorimetry at SND: techniques and performances on physics

abstract:
  SND (Spherical Neutral Detector) is a general purpose nonmagnetic detector,
successfully operating at Novosibirsk VEPP-2M collider during last four years
in the center of mass energy range from 400 MeV up to 1400 MeV. Its crucial
part is a 3-layer, fine grained, spherical NaI(Tl) electromagnetic calorimeter
consisted of 1632 individual counters. Here we present a detailed description
of the calorimeter and its performance, including such topics as calorimeter
design, electronics, calibration, energy and spatial resolutions, particle
identification. The calorimeter performance is illustrated by examples from the
current studies of different physical processes.


title: Measurement of $A_c$ with charmed mesons at SLD

abstract:
  We present a direct measurement of the parity-violation parameter A_c. The
measurement is based on 550k Z^0 decays collected by the SLD detector. The mean
electron-beam polarization is |P_e| = 73 %. The tagging of c-quark events was
performed using two methods: The exclusive reconstruction of D^*+, D^+, and D^0
mesons, and the inclusive P_T spectrum of soft-pions (pi_s) in the decay of
D^*+ -> D^0 pi_s^+. The results of these two methods are combined to give A_c =
0.688 +- 0.035(stat.) +- 0.025(sys.) (preliminary).


title:
Perspectives of Double Beta and Dark Matter Search as Windows to New
  Physics

abstract:
  Nuclear double beta decay provides an extraordinarily broad potential to
search for beyond Standard Model physics, probing already now the TeV scale, on
which new physics should manifest itself. These possibilities are reviewed
here.


title: Neural Networks for Analysis of Top Quark Production

abstract:
  Neural networks (NNs) provide a powerful and flexible tool for selecting a
signal from a larger background. The D0 collaboration has used them extensively
in studying t-tbar decays. NNs were essential to the measurement of the t-tbar
production cross section in the all-jets channel (t tbar -> b bbar qqqq, and
were also used in the measurement of the mass of the top quark in the
lepton+jets channel (t tbar -> b bbar l nu q qbar). This paper will describe
two new applications of neural networks to top~quark analysis: the search for
single top~quark production, and an effort to increase the sensitivity in the
dilepton channel t tbar -> b bbar e mu nu nu beyond that achieved in the
published analysis.


title: Status and Prospects of Supersymmetry Searches at Colliders

abstract:
  Experiments at particle colliders have reached center of mass energies well
above 100 GeV, equivalent to temperatures which existed shortly after the big
bang. These experiments, testing the initial conditions of the universe have,
with great precision, established the Standard Model of Particle Physics. In
contrast, the existence of the Higgs boson and perhaps Supersymmetry remain
speculative, as todays searches have failed to find signs of their existence.
However, the next generation of high energy collider experiments and especially
CERN's 14 TeV LHC, expected to start operation in the year 2005, should lead
either to the discovery of the Higgs and Supersymmetry or disprove todays
theoretical ideas.


title: Determination of the LEP centre-of-mass energy from Zgamma events

abstract:
  Radiative returns to the Z resonance (Zgamma events) are used to determine
the LEP2 centre-of-mass energy from the data collected with the ALEPH detector
in 1997. The average centre-of-mass energy is measured to be:
  E_CM = 182.50 +- 0.19(stat) +- 0.08(syst) GeV
  in good agreement with the precise determination by the LEP energy working
group of 182.652 +- 0.050 GeV. If applied to the measurement of the W mass, its
precision translates into a systematic error on M_W which is smaller than the
statistical error achieved from the corresponding dataset.


title:
Measurement of the Transverse Momentum Distributions of W and Z Bosons
  Produced in pbar p Collisions at sqrt(s) = 1.8 TeV

abstract:
  We present measurements of the transverse momentum distribution of W and Z
bosons produced in pbar p collisions at sqrt(s) = 1.8 TeV. The data were
collected with the D0 detector at Fermilab during 1994-1996 Tevatron run. The
results are in good agreement with theoretical predictions based on the
perturbative QCD and soft gluon resummation combined calculation over the
entire measured pt range p_T = 0-200 GeV/c).


title: A new measurement of the properties of the rare decay K -> pi+ e+ e-

abstract:
  A large low-background sample of events (10300) has been collected for the
rare decay of kaons in flight K+ -> pi+ e+ e- by experiment E865 at the
Brookhaven AGS. The decay products were accepted by a broad band
high-resolution charged particle spectrometer with particle identification. The
branching ratio (2.94 +- 0.05(stat.) +- 0.13(syst.) +- 0.05(model))*10**{-7}
was determined normalizing to events from the decay chain K+ -> pi+ pi0; pi0 ->
e+ e- gamma. From the analysis of the decay distributions the vector nature of
this decay is firmly established now, and limits on scalar and tensor
contributions are deduced. From the (e+ e-) invariant mass distribution the
decay form factor f(z)=f0(1+ delta*z) (z=M(ee)**2/m(K)**2) is determined with
delta=2.14 +- 0.13 +- 0.15. Chiral QCD perturbation theory predictions for the
form factor are also tested, and terms beyond leading order O(p**4) are found
to be important.


title: Rare Decays of the $\eta^{'}$

abstract:
  We have searched for the rare decays of the eta prime meson to e+ e- eta, e+
e- pizero, e+ e- gamma, and e mu in hadronic events at the CLEO II detector.
The search is conducted on 4.80 fb^-1 of e+ e- collisions at the Cornell
Electron Storage Ring. We find no signal in any of these modes, and set 90%
confidence level upper limits on their branching fractions of 2.4 X 10^-3, 1.4
X 10^-3, 0.9 X 10^-3, and 4.7 X 10^-4, respectively. We also investigate the
Dalitz plot of the common decay of the eta prime to pi+ pi- eta. We fit the
matrix element with the Particle Data Group parameterization and find Re(alpha)
= -0.021 +- 0.025, where alpha is a linear function of the kinetic energy of
the eta.


title:
A photon calorimeter using lead tungstate crystals for the CEBAF Hall A
  Compton polarimeter

abstract:
  The performances of the calorimeter of the Jlab Hall A Compton Polarimeter
have been measured using the Mainz tagged photon beam.


title:
A Search for Dilepton Signatures from Minimal Low-Energy Supergravity in
  $p\bar{p}$ Collisions at $\sqrt{s}=1.8$ TeV

abstract:
  We report on a search for supersymmetry using the D\O detector. The 1994-1996
data sample of $\sqrt{s}=1.8$ TeV $p\bar{p}$ collisions was analyzed for events
containing two leptons ($e$ or $\mu$), two or more jets, and missing transverse
energy. Assuming the minimal supergravity model, with $A_0=0$ and $\mu<0$,
various thresholds were employed to optimize the search. No events were found
beyond expectation from background. We set a lower limit at the 95% C.L. of 255
GeV/$c^2$ for equal mass squarks and gluinos for $\tan{\beta}=2$, and present
exclusion contours in the $(m_0,m_{1/2})$ plane for $\tan{\beta}=2$--6.


title: The search for Higgs particles at LEP

abstract:
  The results of the experimental searches for Higgs particles at LEP, using
the data collected at centre-of-mass energies up to 189 GeV, are reviewed and
the prospects for the near future outlined.


title: New Measurement of Ab at the Z Resonance using a Vertex-Charge Technique

abstract:
  We present a new preliminary measurement of the parity-violation parameter Ab
using a self-calibrating vertex-charge technique. In the SLD experiment we
observe hadronic decays of polarized Z bosons produced in collisions between
longitudinally polarized electrons and unpolarized positrons at the SLAC Linear
Collider. A sample of bb events is selected using the topologically
reconstructed mass of B hadrons. From out 1996-8 data sample of approximately
400,000 hadronic Z decays, we obtain Ab = 0.897 +/- 0.027 (stat) +0.036/-0.034
(syst).


title:
Measurement of the B+ and B0 Lifetimes using Topological Vertexing at
  SLD

abstract:
  The lifetimes of B+ and B0 mesons have been measured using the entire sample
of 550,000 hadronic Z0 decays collected by the SLD experiment at the SLC
between 1993 and 1998. In this paper, we describe the inclusive analysis of the
350,000 hadronic Z0 decays collected in 1997-98 with the upgraded SLD vertex
detector. In this data period, a high statistics sample of 30903 (20731)
charged (neutral) vertices with good charge purity is obtained. The charge
purity is enhanced by using the vertex mass, the SLC electron beam polarization
(73% for 1997-8) and an opposite hemisphere jet charge technique. Combining the
results of this data sample with the results from the earlier data yield the
following preliminary values: $\tau_{B^+}=1.623\pm0.020($stat$)\pm0.034$(syst)
ps, $\tau_{B^0}=1.589\pm0.021($stat$)\pm0.043$(syst) ps, $\tau_{B^+}/\tau_{B^0}
= 1.037\pm^{0.025}_{0.024}($stat$) \pm0.024$(syst).


title: Direct Measurement of B(D0->phiX0) and B(D+->phiX+)

abstract:
  The first measurement of B(0->phi X0) and an upper limit for B(D+->phi X+)
are determined from 22.3 pb-1 of e+e- annihilation data at a C. M. energy of
4.03 GeV. The data were recorded by the Beijing Spectrometer (BES) at BEPC. A
recoil charge method is applied for the first time to charm threshold data to
determine the charge of the D meson in the recoil from 9054+-309+-416
reconstructed D0, D+ mesons. The branching fractions B(D->phiX0)
=(1.71+0.76-0.71+-0.17)%, and B(D+->phiX+) <1.8% are determined from 10 events
with a reconstructed D and a recoiling phi. In addition, a 90% C.L. upper limit
of B(D+->phi e+X0)<1.6% is determined from a search for semileptonic decays of
the D+.


title:
Measurement of the B0 anti-B0 oscillation frequency using l- D*+ pairs
  and lepton flavor tags

abstract:
  The oscillation frequency Delta-md of B0 anti-B0 mixing is measured using the
partially reconstructed semileptonic decay anti-B0 -> l- nubar D*+ X. The data
sample was collected with the CDF detector at the Fermilab Tevatron collider
during 1992 - 1995 by triggering on the existence of two lepton candidates in
an event, and corresponds to about 110 pb-1 of pbar p collisions at sqrt(s) =
1.8 TeV. We estimate the proper decay time of the anti-B0 meson from the
measured decay length and reconstructed momentum of the l- D*+ system. The
charge of the lepton in the final state identifies the flavor of the anti-B0
meson at its decay. The second lepton in the event is used to infer the flavor
of the anti-B0 meson at production. We measure the oscillation frequency to be
Delta-md = 0.516 +/- 0.099 +0.029 -0.035 ps-1, where the first uncertainty is
statistical and the second is systematic.


title: Development of a Laser Wire Beam Profile Monitor (I)

abstract:
  A conceptual design work and a basic experimental study of a new beam profile
monitor have been performed. The monitor will be used to measure emittance of
an electron beam in the ATF damping ring at KEK, in which the transverse beam
size of about 10 micron is expected. It utilizes a CW laser and an optical
cavity, instead of a material wire, to minimize interference with an electron
beam. A laser beam with a very thin waist is realized by employing the cavity
of nearly concentric mirror configuration while the intensity is amplified by
adjusting the cavity length to a Fabry-Perot resonance condition. We built a
test cavity to establish a method to measure important parameters such as a
laser beam waist and a power enhancement factor. Three independent methods were
examined for the measurement of the beam waist. It was found that the cavity
realized the beam waist of 20 micron with the power enhancement factor of 50.


title:
A coupled channel analysis of the centrally produced K+K- and pi+pi-
  final states in pp interactions at 450 GeV/c

abstract:
  A coupled channel analysis of the centrally produced K+K- and pi+pi- final
states has been performed in pp collisions at an incident beam momentum of 450
GeV/c. The pole positions and branching ratios to pipi and KK of the f0(980),
f0(1370), f0(1500) and f0(1710) have been determined. A systematic study of the
production properties of all the resonances observed in the pi+pi- and K+K-
channels has been performed.


title: Observeration 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 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 a tau radiatively decaying to a muon is measured to
be (3.61+-0.16+-0.35)*10^{-3}, and to an electron is
(1.75+-0.06+-0.17)*10^{-2}. The branching fractions are in agreement with the
Standard Model theoretical predictions. All quoted results are preliminary.


title: Charged Track Multiplicity in B Meson Decay

abstract:
  We have used the CLEO II detector to study the multiplicity of charged
particles in the decays of B mesons produced at the $\Upsilon(4S)$ resonance.
Using a sample of 1.5 x 10^6 B meson pairs, we find the mean inclusive charged
particle multiplicity to be 10.71 +- 0.02 +0.21/-0.15 for the decay of the
pair. This corresponds to a mean multiplicity of 5.36 +- 0.01 +0.11/-0.08 for a
single B meson. Using the same data sample, we have also extracted the mean
multiplicities in semileptonic and nonleptonic decays. We measure a mean of
7.82 +- 0.05 +0.21/-0.19 charged particles per $B\bar{B}$ decay when both
mesons decay semileptonically. When neither B meson decays semileptonically, we
measure a mean charged particle multiplicity of 11.62 +- 0.04 +0.24/-0.18 per
$B\bar{B}$ pair.


title: Plans for Spin Physics at RHIC

abstract:
  Polarized proton collisions will be studied at RHIC up to a total center of
mass energy of 500 GeV, starting in 2002. An overview of the RHIC-spin program,
and the critical components of the PHENIX and STAR detectors for spin
experiments, is presented. The premier experiment within the RHIC-spin program
is the determination of the fraction of the proton's spin carried by gluons. A
detailed analysis of how accurately this fraction can be determined by the STAR
experiment at RHIC is presented.


title: Subjet Multiplicity in Quark and Gluon Jets at D0

abstract:
  We measure the subjet multiplicity M in jets reconstructed with a successive
combination type of jet algorithm (k_T). We select jets with 55<E_T<100 GeV and
| \eta | < 0.5. We compare similar samples of jets at sqrt{s} = 1800 and 630
GeV. The HERWIG Monte Carlo simulation predicts that 59% of the jets are gluon
jets at \sqrt{s} = 1800, and 33% at sqrt{s} = 630. Using this information, we
extract the subjet multiplicity in quark (M_q) and gluon (M_g) jets. We also
measure the ratio $R\equiv \frac{\left< M_{q}\right> -1}{% \left< M_{g}\right>
-1}= 1.91 \pm 0.04{\rm(stat)} ^{+0.23}_{-0.19} {\rm(sys)}$.


title:
Search for Higgs Bosons and Other Massive States decaying into two
  Photons in e+e- Collisions at 189 GeV

abstract:
  A search is described for the generic process e+e- to X Y, where X is a
neutral heavy scalar boson decaying into a pair of photons, and Y is a neutral
heavy boson (scalar or vector) decaying into a fermion pair. The search is
motivated mainly by the cases where either X, or both X and Y, are Higgs
bosons. In particular, we investigate the case where X is the Standard Model
Higgs boson and Y the Z0 boson. Other models with enhanced Higgs boson decay
couplings to photon pairs are also considered. The present search combines the
data set collected by the OPAL collaboration at 189 GeV collider energy, having
an integrated luminosity of 182.6pb-1, with data samples collected at lower
energies. The search results have been used to put 95% confidence level bounds,
as functions of the mass of X, on the product of the cross-section and the
relevant branching ratios, both in a model independent manner and for the
particular models considered.


title:
A study of B0s meson oscillation using hadronic Z0 decays containing
  leptons

abstract:
  A sample of Z decays containing b-flavoured hadrons is tagged using leptons,
and events having precise proper time measurements are selected. These events
are used to study Bs oscillations. using the lepton to tag the decay b-flavour
and jet charge or a second lepton, where available, to determine the produced
b-flavour. The flavour (b or b-bar) at decay is determined from the lepton
charge while the flavour at production is determined from jet charge or the
charge of a second lepton, where available. The experiment was not able to
resolve the oscillatory behaviour, and we deduce that the Bs oscillation
frequency Delta(ms)> 5.2ps-1 at the 95% confidence level.


title: Observation of the Cabibbo-suppressed decay Xi_c+ -> p K- pi+

abstract:
  We report the first observation of the Cabibbo-suppressed charm baryon decay
Xi_c+ -> p K- pi+. We observe 150 +- 22 events for the signal. The data were
accumulated using the SELEX spectrometer during the 1996-1997 fixed target run
at Fermilab, chiefly from a 600 GeV/c Sigma- beam. The branching fractions of
the decay relative to the Cabibbo-favored Xi_c+ -> Sigma+ K- pi+ and Xi_c+ ->
X- pi+ pi+ are measured to be B(Xi_c+ -> p K- pi+)/B(Xi_c+ -> Sigma+ K- pi+) =
0.22 +- 0.06 +- 0.03 and B(Xi_c+ -> p K- pi+)/B(Xi_c+ -> X- pi+ pi+) = 0.20 +-
0.04 +- 0.02, respectively.


title:
Combined SLD Measurement of Ab at the Z Resonance using Various
  Techniques

abstract:
  We present a new preliminary combination of measurements of the
parity-violation parameter Ab made by the SLD collaboration using various
experimental techniques. The techniques differ in detail, but in general a
sample of bb events is selected or enhanced by using the topologically
reconstructed mass of the separated vertices formed by decaying B hadrons. The
direction of the b(bbar) quark is signed by one of four final state tags: jet
charge, vertex charge, leptons, or identified K+- from the b vertex. We account
for statistical and systematic correlations between the four analyses to arrive
at our combined result: Ab=0.905 +/- 0.017 {stat} +/- 0.020 (syst).


title: Multi-photon production in e+e- collisions at sqrt(s)= 189 geV

abstract:
  The process e+e- to 2 (or 3) gammas is studied using data recorded with the
OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189
GeV corresponds to a total integrated luminosity of 178 pb-1. The measured
cross-section agrees well with the expectation from QED. A fit to the angular
distribution is used to obtain improved limits at 95% CL on the QED cut-off
parameters: Lambda+ > 304 GeV and Lambda- > 295 GeV as well as a mass limit for
an excited electron, Me* > 306 GeV assuming equal e*egamma and eegamma
couplings. Graviton exchange in the context of theories with higher dimensions
is excluded for scales G+ < 660 GeV and G- < 634 GeV. No evidence for resonance
production is found in the invariant mass spectrum of photon pairs. Limits are
obtained for the cross-section times branching ratio for a resonance decaying
into two photons and produced in association with another photon.


title:
Direct Measurement of A_c using Inclusive Charm Tagging at the SLD
  Detector

abstract:
  We report a new measurement of A_c using data obtained by SLD in 1993-98.
This measurement uses a vertex tag technique, where the selection of a c
hemisphere is based on the reconstructed mass of the charm hadron decay vertex.
The method uses the 3D vertexing capabilities of SLD's CCD vertex detector and
the small and stable SLC beams to obtain a high c-event tagging efficiency and
purity of 28% and 82%, respectively. Charged kaons identified by the CRID
detector and the charge of the reconstructed vertex provide an efficient
quark-antiquark tag, with the analyzing power calibrated from the data. We
obtain a preliminary result of A_c = 0.603 \pm 0.028 \pm 0.023


title: Direct Measurement of A_b using Charged Kaons at the SLD Detector

abstract:
  We report a new measurement of A_b using data obtained by SLD in 1997-98.
This measurement uses a vertex tag technique, where the selection of a b
hemisphere is based on the reconstructed mass of the bottom hadron decay
vertex. The method uses the 3D vertexing capabilities of SLD's CCD vertex
detector and the small and stable SLC beams to obtain a high b-event tagging
efficiency and purity of 78% and 97%, respectively. Charged kaons identified by
the CRID detector provide an efficient quark-antiquark tag, with the analyzing
power calibrated from the data. We obtain a preliminary result of A_b = 0.997
\pm 0.044 \pm 0.067


title:
Measurement of the Production Rate of Charm Quark Pairs from Gluons in
  Hadronic Z0 Decays

abstract:
  The rate of secondary charm-quark-pair production has been measured in 4.4
million hadronic Z0 decays collected by OPAL. By selecting events with three
jets and tagging charmed hadrons in the gluon jet candidate using leptons and
charged D* mesons, the average number of secondary charm-quark pairs per
hadronic event is found to be (3.20+-0.21+-0.38)x10-2.


title: Search for Neutral Higgs Bosons in e+e- Collisions at sqrt(s) ~189GeV

abstract:
  A search for neutral Higgs bosons has been performed with the OPAL detector
at LEP, using approximately 170 pb-1 of e+e- collision data collected at
sqrt(s)~189GeV. Searches have been performed for the Standard Model (SM)
process e+e- to H0Z0 and the MSSM processes e+e- to H0Z0, A0h0. The searches
are sensitive to the b b-bar and tau antitau decay modes of the Higgs bosons,
and also to the MSSM decay mode h0 to A0A0. OPAL search results at lower
centre-of-mass energies have been incorporated in the limits we set, which are
valid at the 95% confidence level. For the SM Higgs boson, we obtain a lower
mass bound of 91.0 GeV. In the MSSM, our limits are mh>74.8GeV and mA>76.5GeV,
assuming tan(beta)>1, that the mixing of the scalar top quarks is either zero
or maximal, and that the soft SUSY-breaking masses are 1 TeV. For the case of
zero scalar top mixing, we exclude values of tan(beta) between 0.72 and 2.19.


title:
Measurement of D*+- Cross Sections and the Charm Contribution to the
  Structure Function of the Proton in Deep Inelastic Scattering at HERA

abstract:
  We present measurements on D*+- production cross sections in deep inelastic
e+p scattering with 1<Q^2<600 GeV^2 and 0.02<y<0.7 in two restricted kinematic
regions in p_t(D*) and eta(D*). The decay channels D*+ -> D0 pi+ with
subsequent decay D0 -> K- pi+ or D0 -> K- pi+ pi+ pi- (+c.c) are used. The
cross sections are extrapolated to the full kinematic region to determine the
charm contribution to the proton structure function.


title: A CCD vertex deetctor for a high-energy linear e+e- collider

abstract:
  I present a summary of the experience with CCD-based vertex detectors at the
SLD experiment at SLAC, and discuss their advantages for use at a future
high-energy e+e- collider. The extensive R+D programme to improve further the
vertexing capabilities of CCD detectors is also outlined.


title: Status of gamma-gamma, gamma-electron colliders

abstract:
  This report on Photon Colliders briefly reviews three main issues: physics
motivation, possible parameters and technical feasibility, plans of works and
international cooperation. New scheme of laser optics at the interaction region
is described which can drastically (at least by one order) reduce the cost of
the laser system.

categories: hep-ex hep-ph physics.acc-ph physics.optics


title:
An Improved Direct Measurement of Leptonic Coupling Asymmetries with
  Polarized $Z^0$'s

abstract:
  We report new direct measurements of the $Z^0$-lepton coupling asymmetry
parameters $A_e$, $A_{\mu}$ and $A_{\tau}$, with polarized $Z^0$'s collected by
the SLD detector at the SLAC Linear Collider. The parameters are extracted from
the measurement of the left-right-forward-backward asymmetries for each lepton
species. The 1996, 1997 and 1998 SLD runs are included in this analysis and
combined with published data from the 1993-95 runs. Preliminary results are
$A_e = 0.1558 \pm 0.0064$, $A_{\mu}=0.137 \pm 0.016 $ and $A_{\tau}=0.142 \pm
0.016$. If lepton universality is assumed, a combined asymmetry parameter
$A_{l} = 0.1523 \pm 0.0057$ results. This translates into an effective weak
mixing angle $\sin^2\theta^{eff}_W = 0.23085 \pm 0.00073$ at the $Z^0$
resonance.


title:
Search for pair-produced leptoquarks in e+e- interactions at sqrt(s) =
  183 GeV

abstract:
  A search for pair-produced leptoquarks has been performed using a sample of
e+e- collision events collected by the OPAL detector at LEP at e+e-
centre-of-mass energies of about 183 GeV. The data sample corresponds to an
integrated luminosity of 55.9 pb-1. The leptoquarks were assumed to be produced
via couplings to the photon and the Z0 and then to decay within a single
fermion generation. No evidence for contributions from leptoquark pair
production processes was observed. Lower limits on scalar and vector leptoquark
masses are obtained. The existing limits are improved in the region of large
decay branching ratio to quark-neutrino.


title:
Tests of the Standard Model and Constraints on New Physics from
  Measurements of Fermion-pair Production at 189 GeV at LEP

abstract:
  Cross-sections and angular distributions for hadronic and lepton pair final
states in e+e- collisions at a centre-of-mass energy near 189 GeV, measured
with the OPAL detector at LEP, are presented and compared with the predictions
of the Standard Model. The results are used to measure the energy dependence of
the electromagnetic coupling constant alpha_em, and to place limits on new
physics as described by four-fermion contact interactions or by the exchange of
a new heavy particle such as a sneutrino in supersymmetric theories with
R-parity violation. A search for the indirect effects of the gravitational
interaction in extra dimensions on the mu+mu- and tau+tau- final states is also
presented.


title:
Observation of a Broad L=1 $c\bar{q}$ State in $B^{-}\to
  D^{*+}\pi^{-}\pi^{-}$ at CLEO

abstract:
  Using 4.7 fb^-1 of data taken at CESR at energies at and near the Upsilon(4S)
we have studied the decay B- -> D{*+}pi-pi- (and its conjugate). We observe a
new, broad charmed meson state, which we interpret as D_J(j=1/2), in its decay
to D{*+}pi-. Our preliminary results indicate the mass and width of this L=1
state to be m = (2461 +41/-3} +/-10 +/-32) MeV and Gamma = (290 +101/-79 +/-26
+/-36) MeV, with the third uncertainty associated with the parameterization of
the relative strong phases. In addition we have measured several new branching
fractions of charged B mesons. All quoted results are preliminary.


title:
Hadroproduction of the Chi1 and Chi2 States of Charmonium in 800 GeV/c
  Proton-Silicon Interactions

abstract:
  The cross sections for the hadroproduction of the Chi1 and Chi2 states of
charmonium in proton-silicon collisions at sqrt{s}=38.8 GeV have been measured
in Fermilab fixed target Experiment 771. The Chi states were observed via their
radiative decay to J/psi+gamma, where the photon converted to e+e- in the
material of the spectrometer. The measured values for the Chi1 and Chi2 cross
sections for x_F>0 are 263+-69(stat)+-32(syst) and 498+-143(stat)+-67(syst) nb
per nucleon respectively. The resulting sigma(Chi1}/sigma(Chi2) ratio of
0.53+-0.20(stat)+-0.07(syst), although somewhat larger than most theoretical
expectations, can be accomodated by the latest theoretical estimates.


title: Search for Neutral Heavy Leptons in a High-Energy Neutrino Beam

abstract:
  A search for neutral heavy leptons (NHLs) has been performed using an
instrumented decay channel at the NuTeV (E-815) experiment at Fermilab. The
decay channel was composed of helium bags interspersed with drift chambers, and
was used in conjunction with the NuTeV neutrino detector to search for NHL
decays. The data were examined for NHLs decaying into muonic final states (mu
mu nu, mu e nu, mu pi, and mu rho); no evidence has been found for NHLs in the
0.25 - 2.0 GeV mass range. This analysis places limits on the mixing of NHLs
with standard light neutrinos at a level up to an order of magnitude more
restrictive than previous search limits in this mass range.


title:
Measurement of D*+- production and the charm contribution to F_2 in deep
  inelastic scattering at HERA

abstract:
  The production of D*+-(2010) mesons in deep inelastic scattering has been
measured in the ZEUS detector at HERA using an integrated luminosity of 37
pb^-1. The decay channels D*+ -> D0 pi+(+c.c.), with D0 -> K- pi+ or D0 ->K-
pi- pi+ pi+, have been used to identify the D mesons. The e+p cross section for
inclusive D*+- production with 1<Q^2<600 GeV^2 and 0.02<y<0.7 is 8.31 +-
0.31(stat.) +0.30-0.50(syst.) nb in the kinematic region 1.5< pT(D*+-)<15 GeV
and |eta(D*+-)|<1.5. Differential cross sections are consistent with a
next-to-leading-order perturbative-QCD calculation when using
charm-fragmentation models which take into account the interaction of the charm
quark with the proton remnant.
  The observed cross section is extrapolated to the full kinematic region in
pT(D*+-) and eta(D*+-) in order to determine the charm contribution,
F^ccbar_2(x,Q^2), to the proton structure function. The ratio
  F^ccbar_2/F_2 rises from ~10% at Q^2 ~1.8 GeV^2 to ~30% at Q^2 ~130 GeV^2 for
x values in the range 10^-4 to 10-3.


title: A Study of Three-Prong Tau Decays with Charged Kaons

abstract:
  From an analysis of the ionisation energy loss of charged particles selected
from a sample of 147926 e+e- -> tau+tau- candidates recorded in the OPAL
detector at e+e- centre-of-mass energies near the Z0 resonance, we determine
the branching ratios: BR(tau- -> nu_tau K- pi- pi+ (pi0)) = 0.343 +- 0.073 +-
0.031 % BR(tau- -> nu_tau K- pi- K+ (pi0)) = 0.159 +- 0.053 +- 0.020 % where
the (pi0) notation refers to decay modes with or without an accompanying
pizero. The tau- -> nu_tau K- pi- pi+ (pi0) final states occurring through tau-
-> nu_tau K- K_s (pi0) are treated as background in this analysis. We also
examine the resonant structure of tau- -> nu_tau K- pi- pi+ candidates. Under
the assumption that the resonant structure is dominated by the K_1 resonances,
we determine the ratio of the BR (tau- -> K_1(1270)) to the sum of the BRs (tau
-> K_1(1270) and (tau -> K_1(1400)) to be 0.71 +- 0.16 +- 0.11. In all results,
the first uncertainties are statistical and the second are systematic.


title: First Observation of the Decay $B \to J/\psi \phi K$

abstract:
  We present the first observation of the decay B->J/psi phi K. Using 9.6
million B meson pairs collected with the CLEO detector, we have observed 10
fully reconstructed B->J/psi phi K candidates, whereas the estimated background
is 0.5+/-0.2 events. We obtain a branching fraction of Br(B->J/psi phi K) =
(8.8+3.5/-3.0(stat)+/-1.3(syst))*10^-5. This is the first observed $B$ meson
decay requiring the creation of an additional s sbar quark pair.


title: QCD and gamma-gamma interactions at a high-energy linear e+e- collider

abstract:
  A summary is presented of the key strong-interaction measurements that could
be made at a high-energy, high-luminosity e+e- collider


title: Search for neutral Higgs bosons in e+e- collisions at sqrt{s} <= 196 GeV

abstract:
  A preliminary search for neutral Higgs bosons is performed in the data
collected by ALEPH in 1999, corresponding to integrated luminosities of 29.0
and 69.5 pb^-1 at centre-of-mass energies of 191.6 and 195.6 GeV respectively.
No evidence for a signal is found. Combined with the lower energy ALEPH data,
this observation leads to a 95% confidence level lower mass limit of 98.8
GeV/c^2 for the Standard Model Higgs boson. In the MSSM, the lower limit for
the mass of the lightest CP-even Higgs boson h, is found to be 85.2 GeV/c^2 for
all values of tan(beta)>=1.


title:
Evidence of Color Coherence Effects in W+jets Events from ppbar
  Collisions at sqrt(s) = 1.8 TeV

abstract:
  We report the results of a study of color coherence effects in ppbar
collisions based on data collected by the D0 detector during the 1994-1995 run
of the Fermilab Tevatron Collider, at a center of mass energy sqrt(s) = 1.8
TeV. Initial-to-final state color interference effects are studied by examining
particle distribution patterns in events with a W boson and at least one jet.
The data are compared to Monte Carlo simulations with different color coherence
implementations and to an analytic modified-leading-logarithm perturbative
calculation based on the local parton-hadron duality hypothesis.


title:
Charmless Hadronic B Decays to Exclusive Final States with a
  $K^{*},\rho,\omega$, or $\phi$ Meson

abstract:
  We present results of searches for B-meson decays to charmless final states
that include a K*, rho, omega, or phi meson accompanied by a second meson.
Using the entire data sample of 9.7 million BBbar pairs collected with the CLEO
II and CLEO II.V detectors, we observe a signal for the decay B+ -> omega pi+,
and measure a branching fraction of B(B+ -> omega pi+) = (11.3^{+3.3}_{-2.9}
\pm 1.5) \times 10^{-6}. We also see evidence for the decay B0 -> omega K0, and
set limits for the decays B0 -> rho0 pi0 and B0 -> K*0 pi0. In addition to
these new results, we also summarize previous CLEO results on related channels.
All quoted results are preliminary.


title:
Two-Body B Meson Decays to $\eta$ and $\eta^{'}$ - Observation of $B\to
  \eta K^{*}$

abstract:
  In a sample of 19 million produced B mesons we have observed decays B -> eta
K*, and improved our previous measurements of B -> eta' K. The branching
fractions we measure for these decay modes are B(B+ -> eta K*+) = (27.3 +9.6
-8.2 (stat) +- 5.0 (sys)) * 10^(-6), B(B0 -> eta K*0) = (13.8 +5.5 -4.4 +- 1.7)
* 10^(-6), B(B+ -> eta' K+) = (80 +10 -9 +- 8) * 10^(-6), and B(B0 -> eta' K0)
= (88 +18 -16 +- 9) * 10^(-6). We have searched with comparable sensitivity for
related nonstrange decays, and report upper limits for these rates. All quoted
results are preliminary.


title: Observation of CP Violation in K(L)->pi+pi-e+e- Decays

abstract:
  We report the first observation of a manifestly CP violating effect in the
K(L)->pi+pi-e+e- decay mode. A large asymmetry was observed in the distribution
of these decays in the CP-odd and T-odd angle phi between the decay planes of
the e+e- and pi+pi- pairs in the K(L) center of mass system. After acceptance
corrections, the overall asymmetry is found to be 13.6+-2.5 (stat) +-1.2
(syst)%. This is the largest CP-violating effect yet observed integrating over
the entire phase space of a mode and the first such effect observed in an
angular variable.


title: Compilation of D0-D0bar Mixing Predictions

abstract:
  We present a compilation of predictions for the amplitudes of D0-D0bar
mixing.


title: $b\to s\gamma$ Branching Fraction and CP Asymmetry

abstract:
  We present preliminary results on $b \to s \gamma$ from the CLEO experiment.
An updated result on the branching fraction is reported at $\cal{B}$$(b \to s
\gamma) = (3.15 \pm 0.35 \pm 0.32 \pm 0.26)\times 10^{-4}$, where the first
uncertainty is statistical, the second is systematic, and the third for model
dependence. We also describe a new analysis performed to search for CP
asymmetry in $b \to s \gamma$ decays. We observe no such asymmetry and set
conservative limits at $-0.09 <$ $\cal{A}$ $< 0.42$.


title: Results on Diffractive Processes from the HERA Collider Experiments

abstract:
  We review topical results on diffractive processes from the experiments H1
and ZEUS at the HERA electron-proton collider. Emphasis is placed on the
phenomenological and experimental consequences of the discoveries at HERA for
the proposed electron/polarized-ion collider EPIC.


title:
Resonant Structure of $\tau\to 3\pi\pi^{0}\nu_{\tau}$ and $\tau\to
  \omega\pi\nu_{\tau}$ Decays

abstract:
  The resonant structure of the four pion final state in the decay $\tau \to
3\pi\pi^0\nu_\tau$ is analyzed using 4.27 million $\tau^+\tau^-$ pairs
collected by the CLEO II experiment. We search for second class currents in the
decay $\tau \to \omega\pi\nu_\tau$ using spin-parity analysis and establish an
upper limit on the non-vector current contribution. The mass and width of the
$\rho'$ resonance are extracted from a fit to the $\tau \to \omega\pi\nu_\tau$
spectral function. A partial wave analysis of the resonant structure of the
$\tau \to 3\pi\pi^0\nu_\tau$ decay is performed; the spectral decomposition of
the four pion system is dominated by the $\omega\pi$ and $a_1 \pi$ final
states.