2,166 research outputs found
Test results for the V0 detector in ALICE
In this report, we describe the V0 detector, a device made of two arrays of scintillating counters (V0L and V0R) installe d on both sides of the ALICE in teraction vertex. The light yield and the time resolution were measured for several prototype counter s which were tested on the PS T10 beam line and with cosmic rays. Results from the test and from simulations are reported
Results from the test bench of the Geometry Monitoring System of the ALICE Muon Spectrometer
We present the results obtained with the test bench of the Geometry Monitoring System (GMS) for the ALICE Muon Spectrometer. It consists in a mock up, reproducing at full scale, three half planes of the chambers 6, 7 and 8 of the spectrometer. We show that the GMS is able to measure transverse displacements with an accuracy of 1.5 microm. We show also that the resolution deteriorates by a factor 3 to 4 when thermal gradients are generated
The Strange Quark Contribution to the Proton's Magnetic Moment
We report a new determination of the strange quark contribution to the
proton's magnetic form factor at a four-momentum transfer Q2 = 0.1 (GeV/c)^2
from parity-violating e-p elastic scattering. The result uses a revised
analysis of data from the SAMPLE experiment which was carried out at the
MIT-Bates Laboratory. The data are combined with a calculation of the proton's
axial form factor GAe to determine the strange form factor GMs(Q2=0.1)=0.37 +-
0.20 +- 0.26 +- 0.07. The extrapolation of GMs to its Q2=0 limit and comparison
with calculations is also discussed.Comment: 6 pages, 1 figure, submitted to Phys. Lett.
Parity Violation in Elastic Electron-Proton Scattering and the Proton's Strange Magnetic Form Factor
We report a new measurement of the parity-violating asymmetry in elastic electron scattering from the proton at backward scattering angles. This asymmetry is sensitive to the strange magnetic form factor of the proton as well as electroweak axial radiative corrections. The new measurement of A = -4.92±0.61±0.73 ppm provides a significant constraint on these quantities. The implications for the strange magnetic form factor are discussed in the context of theoretical estimates for the axial corrections
Study of dimuon production in Indium-Indium collisions with the NA60 experiment
The NA60 experiment at the CERN-SPS is devoted to the study of dimuon
production in heavy-ion and proton-nucleus collisions. We present preliminary
results from the analysis of Indium-Indium collisions at 158 GeV per nucleon.
The topics covered are low mass vector meson production, J/psi production and
suppression, and the feasibility of the open charm measurement from the dimuon
continuum in the mass range below the J/psi peak.Comment: Contribution at XXXXth Rencontres de Moriond, "QCD and High Energy
Hadronic Interactions
Latest results from NA60
The NA60 experiment has measured the production of muon pairs and of charged
particles in In+In collisions at a beam energy of 158 AGeV. For invariant
dimuon masses below the phi the space-time averaged rho spectral function was
isolated by a novel procedure. It shows a strong broadening but essentially no
shift in mass. The production of J/psi was measured as a function of the
collision centrality. As in previous experiments studying Pb+Pb collisions an
anomalous supression is observed, setting in at approximately 90 participant
nucleons. Using the charged particles the reaction plane was reconstructed. The
elliptic flow of charged particles increases with pt showing a saturation for
pt > 2GeV/c. For the first time azimuthal distributions for J/psi are shown.Comment: 9 pages, 11 figures, talk given at the conference "Strangeness in
Quark Matter 2006 (SQM2006)", March 2006, Los Angeles, USA, accepted for
publication in Journal of Physics
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