A. V. Zarubin

Cathode strip chamber for CMS ME1/1 endcap muon station

Seventy-six serial ME1/1 cathode strip chambers have been produced in Dubna. These chambers are the coordinate detectors of the first muon station of the CMS detector at CERN. This paper describes the design of the chamber, its main mechanical parameters, and the results of the cosmic ray test.

ME1/1 CATHODE STRIP CHAMBERS FOR CMS EXPERIMENT

The ME1/1 cathode strip chambers are the part of the CMS endcap muon system. They were designed and produced in Dubna. The chambers have been installed in the detector and commissioning has been completed. This paper describes chamber readout electronics and presents the results of the tests with cosmicray muons.

Setting the jet energy scale in the CMS calorimeter using events with direct photons

The procedure of setting the jet energy using events with direct photons proposed as one of the methods of jet calibration in the CMS is studied. Based on complete simulation of events in the CMS including the effects of pile-up of additional events for the initial beam luminosity of the accelerator (L = 2 × 1033 cm−2s−1), the rules for event selection during calibration are proposed. Errors of the proposed method due to the background and the radiation in the ISRare estimated.

CMS REMOTE CENTER AT JINR

The dedicated remote center of CMS Experiment at the LHC has been founded in JINR (Dubna). The main mission of the center is operational and efficient monitoring of the CMS detector systems, including the measurements of performance parameters during the prompt data analysis, monitoring of data acquisition and quality of data. Since 2009 the center is involved in remote shifts and operation works of the CMS.

Study of nuclear effects in nucleon structure functions up to and beyond the kinematic limit

An experiment on deep inelastic muon nucleon scattering in order to study the x-dependence of nucleon structure functions and their ratios over a range ofQ2=50–200 GeV2 andx= =0·4–2·0 is proposed. Such measurements performed on a number of nuclei with atomic weights from 2 to 207 provide new information for detailed studies of the EMC effect and test models explaining thex-behaviour of the nucleon structure functions and their ratios. The measurements are decisive for the proof that a quark-parton model of the nucleus describes adequately nuclear structure probed at high energies. The upgraded high luminosity BCDMS spectrometer with improved resolution in transferred energyν can be used for the measurements.

Systematic shifts in jet energy scale from the process \(W \to q\bar q\) in CMS detector

The absolute scale of jet energy set in a CMS experiment using the W mass constraint in (tbar t) events with (W to qbar q) decay is studied. The main effects leading to systematic shifts in the jet-energy scale are identified. Estimations of these shifts are given.

The spatial resolution of the CMS ME1/1 muon station cathode strip chambers with CRAFT08 data

The spatial resolution of the outer part of the ME1/1 muon station has been studied with CRAFT08 (Cosmic Rays At Four Tesla-2008) data at the CMS detector (CERN). The ME1/1 Cathode Strip Chamber (CSC) layer spatial resolution as a function of the CMS solenoid magnetic field is presented. The influence of the strip width and anode wire tilt on the spatial resolution has been studied. Finally, the spatial resolution for the ME1/1 6-layer CSC was calculated and the ME1/1 outer part spatial resolution was estimated.

Measurement of space resolution of endcap hadronic calorimeter CMS using beam testing of CMS HCAL prototype in 2003

Results of measurement of space resolution of the hadronic endcap calorimeter (HE) CMS based on data obtained at testing HE prototype on a pion beam at CERN in 2003 are presented. Polar angle resolution as a function of polar angle and pion energy are determined. Coefficients for transition from the shower center to particle coordinates are calculated.

Study of the anode self-trigger ability of the ME1/1 CMS Endcap Cathode Strip Chamber

The influence of the high background rates on the Cathode Strip Chamber (CSC) anode trigger ability has been studied. The investigation has been made with a P3 prototype of the CSC of ME1/1 Endcap muon station of the CMS experiment (CERN). The work has been done at the Gamma Irradiation Facility (GIF, CERN). P3 has been installed at the SPS X5c muon beam line in a background field of 137Cs source. The CSC timing resolution and the track registration efficiency as a function of gamma rate are presented.

Electromagnetic secondaries and punch-through effects in the CMS ME1/1

The aim of this work is to estimate the shower leakage from the CMS Endcap Hadron calorimeter (HE) due to electromagnetic secondaries and punch-through in the region of the ME1/1 Forward Muon Station. Two configurations are considered: with and without the CMS Endcap Electromagnetic calorimeter (EE). The experimental data have been taken during the combined beam test of CMS subdetectors (HE, ME, RPC, DT) at the CERN H2 beam facility in 2004. Serial CSC chambers (ready for installation in CMS) fully equipped with readout electronics have been exposed. Simulation of a beam test setup has been performed using the GEANT4-based simulation software package OSCAR.