The LHC, a high luminosity proton proton collider to be built at CERN, Geneva, Switzerland will have a total energy of 14 TeV. Two major detectors, CMS and ATLAS, have been approved for construction and are expected to take data in 2005. About one third of the physicist now working in these two detector groups are from the United States. The energy and the intensity will be high enough to probe the 1 TeV mass frontier, specifically searching for the Higgs particles, needed in the ``standard model" to give mass to the elementary particles. Our research group is now working with the CMS detector group. Simulation results for the Higgs as well as the SUSY searches will be presented.
[CA.02] A Review of Experimental Searches for Cold, Dark Matter in the Universe
Frank T. Avignone\ III (Department of Physics & Astronomy, University of South Carolina)
\indent There is broad agreement among the astronomy, astrophysics, and cosmology communities that most of the mass in galactic halos and, in fact, the universe is dark. Popular candidates for dark matter are: heavy Dirac neutrinos, light neutrinos, non-standard coupled weakly interacting massive particles (WIMPs), axions, and the lightest supersymmetric particle (LSP). Large Scale Structure Models that are consistent with the observed fluctuations in the cosmic microwave background radiation require a mixture of \ 70% cold dark matter (CDM), with a Maxwellian distribution having a dispersion velocity of \ 270 km/sec in our galactic halo, and 25% hot dark matter (HDM), and a small component of baryonic dark matter. The early attempts to directly detect dark matter in 1986 have resulted in a large number of serious experimental efforts that have already led to interesting bounds on the masses and coupling constants of such hypothetical particles. A broad overview of these experimental programs will be given. A status report will emphasize those experiments that have already produced results sensitive enough to have had an impact on cosmological models. \end abstract \enddocument
[CA.03] Recent Physics Results from The SLD Detector at the SLAC Linear Collider
Robert S. Kroeger (University of Mississippi)
The SLAC Large Detector (SLD),
including the recently upgraded vertex
detector, will be described. Recent results in electro-weak
and heavy flavor physics for e^+e^- interactions at the Z^0
resonance using SLD's 1993-1995 data samples will be presented, and
prospects for future physics with the detector will be reviewed.
[CA.04] Light-cone quark model predictions for radiative meson decays
Ho-Meoyng Choi, Chueng-Ryong Ji (North Carolina State University)
We investigate the radiative decays of pseudoscalar
(\pi, K,\eta,\eta'), vector(\rho, K^*, ømega, \phi) and axial
vector (A_1) mesons using a simple relativistic constituent quark
model.
For both simplicity and relativity, we take advantage of the
distinguished
features in the light-cone quantization method; the Fock-state
expansion
of meson wavefunctions are not contaminated by the vacuum fluctuation,
(2)
the problem of assigning quantum numbers J^PC to mesons is
circumvented by the Melosh transformation.
Except the well-known constituent quark masses of (u,d,s) quarks and the
spin-averaged meson masses, the only parameter in the model is the
gaussian
parameter \beta which determines the broadness( or sharpness) of
radial wavefunction.
Our overall predictions of pseudoscalar, vector and axial vector
meson radiative decay processes
are remarkably in good agreement with the experimental data.
[CA.05] Direct Photons in pbar-p Collisions at Fermilab
Christopher Shaffer (Florida State University)
The DZero collaboration at Fermilab operates a large, gereral purpose detector to measure the final states of pbar-p collisions at \sqrts=1.8 TeV. The detector features a liquid Argon - Uranium plate sampling calorimeter which provides excellent energy resolution for the measurement of high transverse momentum jets, electrons, muons and photons which are predicted by the Standard Model. A comparison between data and QCD predictions of final states involving a photon and jets will be presented.
[CA.06] An Update on R_b Anomaly
Peter Povinec (University of Alabama)
A substantial decrease in the experimental value of R_b has been reported from LEP recently. Consequently, the gap between theoretical and experimental values of R_b diminishes significantly and SUSY contributions can now fully account for the difference. This can give constraints on squark masses in the SUSY explanation of R_b.
[CA.07] Light Gluino And Jet Experiments At The Tevatron
Igor Terekhov (Dept. of Physics, The University of Alabama)
We discuss implications of the light gluino in jet experiments at the
Tevatron. First, single squark production results in peaks in the dijet mass
spectrum. Second, inclusive E_T distributions are enhanced due to
slower running
of \alpha_s, gluino pair production and squark production. Lastly,
single squark production may result in an inclusive jet angular distribution
different from that in standard QCD.
[CA.08] A Precision Displacement Monitoring System for Silicon Strip Detectors
Mark Behrens, Hans Tuchscherer (University of Alabama), Peter Raics, Gyula Zilizi, Sandor Juhasz, Zoltan Szillasi, Jozsef Szabo, Zsolt Szabo, Tibor Sztaricskai, Sandor Nagy, Gyongyi Marian (Kossuth University, Debrecen, Hungary), Gyorgy Bencze (KFKI, Budapest, Hungary), Antal Adam, Janos Kornis (Technical University, Budapest, Hungary)
The L3 detector at LEP includes a Silicon Microvertex Detector (SMD). To make use of the accurate position measuring capability of the SMD the position of its elements has to be continuously monitored with an even higher accuracy. An optical system (LDMS) serving this purpose will be introduced. It is based on pulsed laser diodes which through a network of optical fibers, distributors, and micro-optical elements illuminate the silicon wafers. The generated signals are collected using the regular SMD read out, thereby also allowing for the testing of that system. Technical aspects and performance of the LDMS will be discussed.
[CA.09] Analysis of the Geometric Stability of the Silicon Microvertex Detector in L3 at LEP
Mark Behrens (University of Alabama)
The use of the Silicon Microvertex Detector (SMD) in precision measurements of fundamental processes is contingent on the accuracy to which its position can be determined. Knowledge of SMD stability is vital in this respect. An analysis technique has been developed for the Laser Displacement Monitoring System (LDMS) to allow for the monitoring of SMD stability. The algorithms and statistical methods are discussed, as well as the results obtained from the 1995 data taking period.
[CA.10] Current Mass quarks in the Proton and Roper Resonance
George Strobel (Physics Dept., Univ. of Georgia), Klara Shitikova (Nuclear Physics, SUNY, Stony Brook)
The three body Dirac equation is solved for the (1/2+)3 configuration in hypercentral approximation using a linear confining potential and a coulombic attractive term. This results in an exponential hyperradial dependence consistent with dipole fits to form factors. The proton magnetic moment is reproduced using 10 MeV quark masses, consistent with current mass values. The Roper resonance is reproduced at 1440 MeV. With confining potentials, the Schmidt limit for bound fermions is not valid for the magnetic moments of bound quarks. Constituent quark masses are not needed in this approach.