GSI Helmholtzzentrum für Schwerionenforschung
A first draft of TRD chamber testing manual is available at www.physi.uni-heidelberg.de/~schicker/trdtest/chamb_v1.pdf
Dear Rainer, the manual looks very good! I have a few questions and comments: 1.1 is the 90Sr source really needed for anything? 2. Chamber leakrate: the maximum allowed leak rate should be specified. 3. Chamber conditioning: - I think the conditions need to be specified: flow rate, required O2 and H2O purity. Is the full drift voltage applied? - O2 and H2O content should enter the database. - can you specify when the conditioning was successful? what is the maximum allowed dark current, at what voltages? 4. Gain uniformity: - which radiation source should be used (and why)? If X-ray tube: which settings are recommended? - Conditions: flow rate, O2 and H2O? With or without drift voltage? Important: which anode voltage (sag!)? - Which level of non-uniformity can be tolerated (standard deviation, maximum deviation)? 5. Gain curve: - at which flow rate, O2, H2O? Which source? Which drift voltage? - what is the recommended DeltaV and Vmax? - should an absolute gain measurement be performed for every chamber (how much effort is this?)? Very important, but also in general: do we insist on a specific gas mixture? Regards, Harry