Efficiency of Finding Muon Track Trigger Primitives in CMS Cathode Strip Chambers

In the CMS Experiment, muon detection in the forward direction is accomplished by cathode strip chambers~(CSC). These detectors identify muons, provide a fast muon trigger, and give a precise measurement of the muon trajectory. There are 468 six-plane CSCs in the system. The efficiency of finding muon trigger primitives (muon track segments) was studied using~36 CMS CSCs and cosmic ray muons during the Magnet Test and Cosmic Challenge~(MTCC) exercise conducted by the~CMS experiment in~2006. In contrast to earlier studies that used muon beams to illuminate a very small chamber area ($< \! 0.01$~m$^2$), results presented in this paper were obtained by many installed CSCs operating {\em in situ} over an area of $\approx \! 23$~m$^2$ as a part of the~CMS experiment. The efficiency of finding 2-dimensional trigger primitives within 6-layer chambers was found to be~$99.93 \pm 0.03\%$. These segments, found by the CSC electronics within $800$~ns after the passing of a muon through the chambers, are the input information for the Level-1 muon trigger and, also, are a necessary condition for chambers to be read out by the Data Acquisition System

CMS physics technical design report : Addendum on high density QCD with heavy ions

Peer reviewe

Nanoscale Hemispheres in Novel Mixed-Valent Uranyl Chromate(V,VI), (C₃NH₁₀)₁₀[(UO₂)₁₃(Cr₁₂⁵⁺O₄₂)(Cr⁶⁺O₄)₆(H₂O)₆](H₂O)₆

The structure of a novel mixed-valent chromium uranyl compound, (C₃NH₁₀)₁₀[(UO₂)₁₃(Cr₁₂⁵⁺O₄₂)­(Cr⁶⁺O₄)₆(H₂O)₆]­(H₂O)₆ (<b>1</b>), obtained by the combination of a hydrothermal method and evaporation from aqueous solutions with isopropylammonium, contains uranyl chromate hemispheres with lateral dimensions of 18.9 × 18.5 Ų and a height of about 8 Å. The hemispheres are centered by a UO₈ hexagonal bipyramid surrounded by six dimers of Cr⁵⁺O₅ square pyramids, UO₇ pentagonal bipyramids, and Cr⁶⁺O₄ tetrahedra. The hemispheres are linked into two-dimensional layers so that two adjacent hemispheres are oriented in opposite directions relative to the plane of the layer. From a topological point of view, the hemispheres have the formula U₂₁Cr₂₃ and can be considered as derivatives of nanospherical cluster U₂₆Cr₃₆ composed of three-, four-, and five-membered rings

Nanoscale Hemispheres in Novel Mixed-Valent Uranyl Chromate(V,VI), (C₃NH₁₀)₁₀[(UO₂)₁₃(Cr₁₂⁵⁺O₄₂)(Cr⁶⁺O₄)₆(H₂O)₆](H₂O)₆

The structure of a novel mixed-valent chromium uranyl compound, (C₃NH₁₀)₁₀[(UO₂)₁₃(Cr₁₂⁵⁺O₄₂)­(Cr⁶⁺O₄)₆(H₂O)₆]­(H₂O)₆ (<b>1</b>), obtained by the combination of a hydrothermal method and evaporation from aqueous solutions with isopropylammonium, contains uranyl chromate hemispheres with lateral dimensions of 18.9 × 18.5 Ų and a height of about 8 Å. The hemispheres are centered by a UO₈ hexagonal bipyramid surrounded by six dimers of Cr⁵⁺O₅ square pyramids, UO₇ pentagonal bipyramids, and Cr⁶⁺O₄ tetrahedra. The hemispheres are linked into two-dimensional layers so that two adjacent hemispheres are oriented in opposite directions relative to the plane of the layer. From a topological point of view, the hemispheres have the formula U₂₁Cr₂₃ and can be considered as derivatives of nanospherical cluster U₂₆Cr₃₆ composed of three-, four-, and five-membered rings

CMS physics technical design report: Addendum on high density QCD with heavy ions

This report presents the capabilities of the CMS experiment to explore the rich heavy-ion physics programme offered by the CERN Large Hadron Collider (LHC). The collisions of lead nuclei at energies ,will probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research is to study the fundamental theory of the strong interaction - Quantum Chromodynamics (QCD) - in extreme conditions of temperature, density and parton momentum fraction (low-x). This report covers in detail the potential of CMS to carry out a series of representative Pb-Pb measurements. These include "bulk" observables, (charged hadron multiplicity, low pT inclusive hadron identified spectra and elliptic flow) which provide information on the collective properties of the system, as well as perturbative probes such as quarkonia, heavy-quarks, jets and high pT hadrons which yield "tomographic" information of the hottest and densest phases of the reaction.0info:eu-repo/semantics/publishe

The CMS experiment at the CERN LHC

The Compact Muon Solenoid (CMS) detector is described. The detector operates at the Large Hadron Collider (LHC) at CERN. It was conceived to study proton-proton (and lead-lead) collisions at a centre-of-mass energy of 14 TeV (5.5 TeV nucleon-nucleon) and at luminosities up to 10(34)cm(-2)s(-1) (10(27)cm(-2)s(-1)). At the core of the CMS detector sits a high-magnetic-field and large-bore superconducting solenoid surrounding an all-silicon pixel and strip tracker, a lead-tungstate scintillating-crystals electromagnetic calorimeter, and a brass-scintillator sampling hadron calorimeter. The iron yoke of the flux-return is instrumented with four stations of muon detectors covering most of the 4 pi solid angle. Forward sampling calorimeters extend the pseudo-rapidity coverage to high values (vertical bar eta vertical bar <= 5) assuring very good hermeticity. The overall dimensions of the CMS detector are a length of 21.6 m, a diameter of 14.6 m and a total weight of 12500 t

The CMS experiment at the CERN LHC

0info:eu-repo/semantics/publishe