With the luminosity upgrade of the LHC machine (SLHC, Super-LHC), the Muon system of the ATLAS experiment at CERN will also need a detector upgrade in the highest rapidity region. MAMMA, Muon ATLAS ...Micromegas Activity, is an ongoing R&D activity with the aim to develop large detectors based on the bulk-Micromegas technology for use in the ATLAS Muon Spectrometer. Micromegas is a good potential candidate for the construction of large muon chambers that combine trigger and tracking capability and can sustain high particle rates expected at the SLHC. A medium size Micromegas prototype, in scale 1:10 of the final chambers, has been built and evaluated in the laboratory and in beam tests at CERN. Results from the analysis of test-beam data are presented. The results indicate that large size Micromegas is a viable candidate for ATLAS Muon upgrade
A precise measurement of the analyzing power AN in proton–proton elastic scattering in the region of 4-momentum transfer squared 0.001<|t|<0.032 (GeV/c)2 has been performed using a polarized atomic ...hydrogen gas jet target and the 100 GeV/c RHIC proton beam. The interference of the electromagnetic spin-flip amplitude with a hadronic spin-nonflip amplitude is predicted to generate a significant AN of 4–5%, peaking at −t≃0.003 (GeV/c)2. This kinematic region is known as the Coulomb nuclear interference region. A possible hadronic spin-flip amplitude modifies this calculable prediction. We present the first precise result of the CNI asymmetry and shape as a function of t. Our data are well described by the CNI prediction with the electromagnetic spin-flip alone and do not support the presence of a large hadronic spin-flip amplitude.
The PP2PP experiment is one of five experiments at the Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory, Long Island, New York. It is designed to measure the elastic ...scattering of protons at
s
= 50–500
GeV. The detector consists of silicon strip detectors mounted in Roman Pots and installed in the RHIC ring 60
m from the interaction region. During the engineering run of 2002 and physics run of 2003 the detectors were inserted as close as 15 mm from the proton beam. An overview of the experiment and details of the detector design and performance will be presented.
The Muon Spectrometer of the ATLAS detector at the LHC is designed to provide high quality stand-alone muon identification, momentum measurement and trigger capabilities with high pseudorapidity ...coverage. Precision tracking at the inner-most station in the high pseudorapidity regions, 2.3 < |eta| < 2.7, is performed by 16 four-layered Cathode Strip Chambers on each end-cap. These are multi-wire proportional chambers with segmented cathodes providing excellent spatial resolution and high counting rate capability. The second cathode of each layer is coarsely segmented, providing the transverse coordinate. The detector level performance of the system is presented. The installation and commissioning effort for the Cathode Strip Chambers is described. Finally, the in situ performance is briefly discussed.
The effect of shadowing on the early state of ultrarelativistic heavy ion collisions is investigated along with transverse energy and hard process production, specifically Drell-Yan, J/{psi}, and ...{upsilon} production. We choose several parton distributions and parametrizations of nuclear shadowing, as well as the spatial dependence of shadowing, to study the influence of shadowing on relevant observables. Results are presented for Au+Au collisions at {radical}(s{sub NN})=200 GeV and Pb+Pb collisions at {radical}(s{sub NN})=5.5 TeV. (c) 2000 The American Physical Society.
The effect of shadowing on the early state of ultrarelativistic heavy ion collisions and transverse energy production is discussed. Results are presented for RHIC Au+Au collisions at
▪ and LHC Pb+Pb ...collisions at
▪.
We report on the first measurement of the single spin analyzing power (AN) at s=200 GeV, obtained by the PP2PP experiment using polarized proton beams at the Relativistic Heavy Ion Collider (RHIC). ...Data points were measured in the four momentum transfer t range 0.01⩽|t|⩽0.03 (GeV/c)2. Our result, averaged over the whole |t| interval is about one standard deviation above the calculation, which uses interference between electromagnetic spin-flip amplitude and hadronic non-flip amplitude, the source of AN. The difference could be explained by an additional contribution of a hadronic spin-flip amplitude to AN.
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