7992585
The simulation of resistive plate chambers in avalanche mode: charge spectra and efficiency
A model to simulate the avalanche formation process and the induced signal in a Resistive Plate Chamber is presented. A first investigation of the effects of various parameters on the performance of this detector is reported.
123170336
NEUTRON-INDUCED SINGLE EVENT UPSET ON THE RPC FRONT-END CHIPS FOR THE CMS EXPERIMENT
Neutrons from a reactor and from a cyclotron have been used to characterise the CMS Resistive Plate Chambers (RPCs) front-end chip to neutron-induced damaging events. Single Event Upset (SEU) cross-sections have been measured up to for different chip thresholds. Tests at a reactor were done with an integrated fast () neutron fluence of and a thermal neutron fluence of . High-energy neutrons from a cyclotron were used up to a fluence of . Data indicate the existence of a chip SEU sensitivity already at thermal energy and a saturated SEU cross-section from 3 to . Values of the SEU cross-sections from the thermal run well agree with those obtained by another CMS group that uses the same technology ( BiCMOS) though with different architecture. Cross-sections obtained with fast neutrons (from to about ) are consistently higher by one order of magnitude compared to the thermal one. The average time between consecutive SEU events in each chip of the CMS barrel RPCs can be estimated to be 1 h.
56416813
Aging study for Resistive Plate Chambers of the CMS Muon Trigger Detector
A long-term aging test of a Resistive Plate Chamber (RPC) was carried out with an intense gamma source. The detector was operated in avalanche mode and had the bakelite surface treated with linseed oil. After the irradiation the estimated dose, charge and fluence were approximately equal to the expected values after 10 years of operation in the CMS barrel region. During and after the irradiation, the RPC performance was monitored with cosmic muons and showed no relevant aging effects. Moreover, no variation of the bakelite resistance was observed.
120049072
The resistive plate chambers for CMS and their simulation
In this paper some results obtained by the CMS Resistive Plate Chamber collaboration during its five years long period of research and development are reported. The importance of the simulation in the design of the Resistive Plate Chambers for CMS is stressed.
15045293
The bakelite for the RPCs of the experiment CMS
Results from aging tests on the bakelite used for the CMS RPCs are presented. Samples of melaminic bakelite were exposed to a heavy gamma and neutron radiation. Data on the bulk resistivity were collected while accumulating gamma and neutron doses and particles fluence up to values well beyond those expected in 10 years of RPCs operation in the barrel region of CMS. The test with gamma radiation was performed at the CERN Gamma Irradiation Facility (GIF) with a 20 Ci 137Cs source. A total absorbed dose of 5 Gy was accumulated during an irradiation period of about one month. The test with both neutron and gamma radiation was held at the Triga Mark II 250 kW reactor located in Pavia. A total of 80 h of exposure were accumulated integrating a neutron and gamma dose of about 80 Gy and a fast neutron fluence of some . Experimental data on dose rate in both the test facilities have been compared to simulation output and show a good agreement.
115001576
Single event effect measurements on the resistive plate chambers front-end chips for the CMS experiment
59579158
Rapidity distributions of strange particles in Pb-Pb at 158 AGeV
The production at central rapidity of KS 0 , Λ , Ξ and Ω particles in Pb-Pb collisions at 158 AGeV has been measured by the NA57 experiment over a centrality range corresponding to the most central 53% of the inelastic Pb-Pb cross section. We present the rapidity distribution of each particle in the central rapidity unit. The distributions are analysed based on hydrodynamical models of the collisions.
166225720
Study of J / ψ production at central rapidity with the ALICE experiment at LHC
119419969
Transverse mass distributions of strange particles produced in Pb-Pb collisions at 158 A GeV/c
Experiment NA57 has collected high statistics, high purity samples of $K^0_s$, $\Lambda$, $\Xi$ and $\Omega$ produced in Pb-Pb collisions at 158 $A$ GeV/$c$. In this paper we present a study of the transverse mass spectra of these particles for a sample of events corresponding to about the most central 55% of the inelastic Pb-Pb cross section. We analyse the transverse mass distributions in the framework of the blast-wave model for the full sample under consideration and, for the first time at the SPS, as a function of the event centrality.
117970185
Search for pentaquarks in WA97 experiment at CERN
The WA97 experiment at CERN has collected data aiming to study strangeness production in heavy ion collisions at 158 A GeV/c; p‐Be data were also taken as reference data. Here we show some results of an analysis of these p‐Be data in order to check for evidence of a recently claimed pentaquark state.
7281568
New results from the NA57 experiment
The production of hyperons in Pb–Pb and p–Be interaction at 40 A GeV/c beam momentum has been measured by the NA57 experiment. Strange particle enhancements at 40 A GeV/c are presented for the first time and compared to those measured at 158 A GeV/c. The transverse mass spectra of high statistics, high purity samples of K0S, Λ, Ξ and Ω particles produced in Pb–Pb collisions at 158 A GeV/c have been studied in the framework of the blast-wave model. The dependence of the freeze-out parameters on particle species and event centrality is discussed.