The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 mu m to 243 mu m. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns.

Performance of the CMS cathode strip chambers with cosmic rays

BELLAN, PAOLO;BISELLO, DARIO;BORSATO, ENRICO;BRANCA, ANTONIO;CARLIN, ROBERTO;DE MATTIA, MARCO;GASPARINI, FABRIZIO;GASPARINI, UGO;GIUBILATO, PIERO;MARGONI, MARTINO;MATTIAZZO, SERENA;MENEGUZZO, ANNA TERESA;NESPOLO, MASSIMO;PERROZZI, LUCA;POZZOBON, NICOLA;RONCHESE, PAOLO;SIMONETTO, FRANCO;TOSI, MIA;A. Triossi;VANINI, SARA;ZOTTO, PIERLUIGI;ZUMERLE, GIANNI;ROSSIN, ROBERTO;