TRD R&D at GSI Results from test beam 2004 Plans for test beam Feb. 06 Measurements with X-ray stand C. Garabatos, GSI
IWTRD Cheile Gradistei C. Garabatos, GSI2 TR + tracking rejection ≤ 10 –2 position resolution ~300 m particle load: 10 5 Hz/cm 2 < 100 ns shaping time material budget reliability (stability, ageing,...)
IWTRD Cheile Gradistei C. Garabatos, GSI3 Solutions under study Classical wire chambers GEMs Straw tubes Name: Transition Radiation Detector 6 mm 2-4 mm
IWTRD Cheile Gradistei C. Garabatos, GSI4 Resolution vs. rate (July 04) (E. Jiménez) Slight degradation with rate Pad size not optimized
IWTRD Cheile Gradistei C. Garabatos, GSI5 9 o incident angle
IWTRD Cheile Gradistei C. Garabatos, GSI6 Pad response function Next: go from 7.5 mm to 7.0 mm pad width
IWTRD Cheile Gradistei C. Garabatos, GSI7 Next test beam Feb Dedicated test beam line in cave C (HTD) Higher rates with N 2 source (factor ~5) Improved set-up –Trigger counters –Chamber pad planes –Readout electronics Dense program
IWTRD Cheile Gradistei C. Garabatos, GSI8 Beam profile in HTD
IWTRD Cheile Gradistei C. Garabatos, GSI9 Trigger scintillators for test beam x4 cm 2 plastics x 1x4 cm 2 plastics
IWTRD Cheile Gradistei C. Garabatos, GSI10 Pad geometry for new prototypes ALICE geometry: 7.5x70 mm 2 CBM geometry: 7x16 mm 2
IWTRD Cheile Gradistei C. Garabatos, GSI11 Readout electronics (H. K. Soltveit) New 0.35 m CMOS 16 channel PASA Submission end of September Enough chips for all test detectors
IWTRD Cheile Gradistei C. Garabatos, GSI12 Chip parameters (H.-K. S.) PerformanceSpecifiedSimulated (typical) Noise1000e for pad capacitance between 5- 10pF Conversion gain12 mV/fC12.6 mV/fC FWHM70 ns Undershoot-1mV Baseline shift-3mV Pad capacitance5-10 pF-
IWTRD Cheile Gradistei C. Garabatos, GSI13 Program High rate performance vs. –Detector flavour and geometry –Gas gain –Gas composition –Incident angle e/ separation vs. radiator type (low rates) –Foil radiator p/ separation at high rates
IWTRD Cheile Gradistei C. Garabatos, GSI14 Measurements with X-ray tube (F. Uhlig, G. Hamar)
IWTRD Cheile Gradistei C. Garabatos, GSI15 Measurements with X-rays Possibility to measure rate dependence on gas gain and gas composition Need careful calibration and extrapolation to charged particles Easy Same set-up will be used for ageing tests
IWTRD Cheile Gradistei C. Garabatos, GSI16 Results with Argon Fit to Mathieson's formula ln(G/G 0 )/G = K R The constant K characterises the chamber and the gas Next: Xenon
IWTRD Cheile Gradistei C. Garabatos, GSI17 Conclusions and outlook We start to know what we need Tracking and TR-ID with MWPC seem feasible at CBM High rates and final performance will be an outcome of –specific, ongoing R&D –detailed, incipient simulations