193 research outputs found
Longitudinal Momentum Fraction X_L for Two High P_t Protons in pp->ppX Reaction
We present an analysis of new data from Experiment E850 at BNL. We have
characterized the inclusive cross section near the endpoint for pp exclusive
scattering in Hydrogen and in Carbon with incident beam energy of 6 GeV. We
select events with a pair of back-to-back hadrons at large transverse momentum.
These cross sections are parameterized with a form
, where is the ratio of the longitudinal momentum
of the observed pair to the total incident beam momentum. Small value of
may suggest that the number of partons participating in the reaction is large
and reaction has a strong dependence on the center-of-mass energy. We also
discuss nuclear effects observed in our kinematic region.Comment: 4 pages, 2 figures, to be published in Proceedings of CIPANP2000,
Quebec, May 22-28, 2000, requires aipproc.sty(included
Energy Dependence of Nuclear Transparency in C(p,2p) Scattering
The transparency of carbon for (p,2p) quasi-elastic events was measured at
beam energies ranging from 6 to 14.5 GeV at 90 degrees c.m. The four momentum
transfer squared q*q ranged from 4.8 to 16.9 (GeV/c)**2. We present the
observed energy dependence of the ratio of the carbon to hydrogen cross
sections. We also apply a model for the nuclear momentum distribution of carbon
to normalize this transparency ratio. We find a sharp rise in transparency as
the beam energy is increased to 9 GeV and a reduction to approximately the
Glauber level at higher energies.Comment: 4 pages, 2figures, submitted to PR
Recent results from Pb-Au collisions at 158 GeV/c per nucleon obtained with the CERES spectrometer
During the 1996 lead run time, CERES has accumulated 42 million events,
corresponding to a factor of 5 more statistics than in 1995 and 2.5 million
events of a special photon-run. We report on the results of the low-mass
ee-pair analysis. Since the most critical item is the poor
signal-to-background ratio we also discuss the understanding of this
background, in absolute terms, with the help of a detailed Monte Carlo
simulation. We show preliminary results of the photon analysis and summarize
the results of the hadron analysis preliminarily reported on already at QM'97Comment: 10 pages, 9 figures, Proceedings of the XIV Int. Conf. on
Nucleus-Nucleus Collisions,Quark Matter 99, Torino, Italy, May 10 - 15, 199
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