1 AMS-02 TRD Status Report Stefan Schael RWTH Aachen TIM Meeting, CERN, June 2001 TRD meeting: Wednesday 16:15 in room !!!

2 TRD Mechanics Octagon Production: 8 panels produced at FVT Aachen machined at IPT, RWTH Aachen glued together at Physics AC-I Bulkhead Production: 6 panels produced at FVT Aachen machined at IPT, RWTH Aachen integrated at Physics AC-I Production Status: EM produced QM in production FM expected for Spetember 2001 Production Status: EM in production QM expected for August 2001 FM expected for September 2001

3 TRD assembly Mechanical accuracy (100  m) of the octagon structure will be verified with a 3D coordinate measuring machine in Aachen. TRD assembly in a clean room with temperature (+/- 1°) and humidity control Test of the full TRD in Aachen on a cosmic stand.

4 TRD Module Production I Production scheme: Straws and stringers are glued together at FVT, Aachen Wire feed through, wire crimping, endpiece assembly and all tests at Physics AC-I Production status: Clean room at FVT ready for mass production the first 2 m long chamber has been produced  EM. feed through of the wires was no problem wire tension has been measured and is well within the specifications

5 Wire tension measurements

6 Gas Gain Measurements

7 Long Term Teststand Study the long term behavior of straw modules m long straw modules, i.e. one gas group operated with Xe/CO2 (80%/20%) in a vacuum vessel use a mass spectrometer to measure the leak rate use a recirculating gas system (P. Fischer, MIT) as for the TRD on the ISS

8 TRD Module Production: Next Steps produce 4 modules (1.4 m long) for space qualification i.e. vibration test, acoustic test, thermo vacuum test, EMI test produce 8 modules (1.8 m long) i.e. 1 gas group for the long term test we expect to start the mass production in September 2001.

9 The fleece material (LRP 375 BK) has been produced and cut to the required width by Freudenberg We have started to cut the radiator to the appropriated length Cleaning of the radiator has also started at the Institute for Organic Chemistry of the RWTH Aachen. We expect to have all radiator material ready for TRD assembly by October 2001 TRD radiator

10 TRD  Upper TOF Combined Thermal Control TOF Power  TRD Power  20 Watt TOF & TRD connected to the same M-Structure Contract has been placed with OHB & CGS

11 Radiative link between the PCB‘s (UFE boards) and the radiator: Next step: TOF & TRD in the same MLI volume

12 First results from the TRD thermal model:

13 TRD temperature monitoring

14 TRD Electronics I

15 60 qualification boards build and tested - no failure - typ. leakage current: < 0.3 nA at 2000V (at room temperature, in air atmosphere, 1 bar ) Thermal cycles performed on 10 qualification boards (-30°C, +60°C) - no change in behaviour Vibration tests executed on 10 qualification boards - no change in behaviour Production of 350 flight boards started Status of the UTE Board

16 Status of the UFE Board Prototype of UFE Board build and tested - full functionality at the readout speed of 1 channel/1 µs - measured noise ~ 5500 electrons Next steps - design, production of qualification boards, with final el. circuit and final board shape

17 TRD Crate MIT/Aachen I => CAENCSIST EMQM 1 QM 2 FMSMTotal crate UPD DC/DC100 LV HV UBP UPSFE UDR JINU UHVG UPC12-42AC III

18 TRD Test Beam Results I 20 layer TRD detector in the test beam at CERN in 2000 we have recorded 3 million events providing signals for protons, electrons, muons and pions at energies from GeV Muon events have been used for an intercalibration of the individual straws to a relative accuracy of 2%.

19 TRD Test Beam Results II The TRD fulfills the specification of: proton rejection < 1% at an electron efficiency of 90% up to 260 GeV

20 TRD Test Beam Results III Likelihood method much more effective for pion rejection than cluster counting Result probably still dominated by pion contamination => it is still an upper limit !!!

21 Summary since Houston we have made a lot of progress on: TRD straw module production and test stands TRD electronic, thanks to M. Capell and R. Battiston TRD thermal control TRD MC simulation the TRD is well within schedule TRD mass budget (378 kg) and power budget (20 Watt) has not changed. test beam results show that the performance to the TRD is well within specifications