München 2009 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

T: Fachverband Teilchenphysik

T 64: Myondetektoren 2

T 64.4: Vortrag

Dienstag, 10. März 2009, 17:45–18:00, A014

Drift velocity and pressure monitoring in the CMS muon chambers — Jens Frangenheim, Thomas Hebbeker, Carsten Heidemann, Hans Reithler, •Lars Sonnenschein, and Daniel Teyssier — III Physikalisches Institut A, RWTH Aachen

The drift velocity in the drift tubes of the CMS muon chambers is a key parameter for the muon trigger and the reconstruction. It should be monitored precisely in order to detect any deviation from the nominal value. Indeed a change of the absolute pressure, a variation of the gas mixture or a contamination of the chamber gas by air could affect the drift velocity. The temperature and fringe B field can also influence its value. The first data taken during the last commissioning phase, using a dedicated chamber built in the Institut IIIA at Aachen are presented.

Another parameter that should be monitored is the pressure inside the muon chambers. First of all, the drift velocity depends on it. In addition, the differential pressure must not exceed a certain value, and the absolute pressure must stay always slightly above the ambient pressure in order to avoid air entering the detectors. The latest pressure monitoring results will be presented.