1 / 17

the new Hydrogen TPC at PSI status report, Gatchina meeting June 14-17, 2004

the new Hydrogen TPC at PSI status report, Gatchina meeting June 14-17, 2004 by Malte Hildebrandt and Claude Petitjean. the TPC at first assembly Oct 2002. short history of TPC development 1997-1999 proposal & development of a new prototype TPC at Gatchina

dnora
Download Presentation

the new Hydrogen TPC at PSI status report, Gatchina meeting June 14-17, 2004

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. the new Hydrogen TPC at PSI status report, Gatchina meeting June 14-17, 2004 by Malte Hildebrandt and Claude Petitjean the TPC at first assembly Oct 2002

  2. short history of TPC development • 1997-1999 proposal & development of a new prototype TPC at Gatchina • 1998-2000 successful test runs at PSI – huge problems with gas purity • and HV stability of the cathode planes (currents) • April 2000 decision to develop high purity TPC‘s (& PC‘s) at Gatchina & PSI • main features: UH vacuum, use only UHV proof bakable materials • (metals, ceramics, glass frames with metal coatings, etc) • develop new soldering technique to mount wires under tensions • May 2003 the PSI-TPC reached -6.5 kV in 10 bar protium (good for mips), • but then developed several hotspots ( back to -4.4 kV) • Aug 2003 stable operation at -4.8 kV (after separation of strip voltage • from upper cathode) – good enough as perfect μ stop detector • Sept/Oct 2003 first successful engineering runs in μE4 area (performance • see other contributions)

  3. PSI design drawing of the new TPC construction with glass frames and ceramic structure bakable to ~ 130 C filling 10 bar protium Ucathodes = 5-6 kV E = 2 kV/cm - vdrift = 0.5 cm/μs sensitive volume (12 x 15 x 30) cm3

  4. TPC anode/cathodes: hotspots verified in Oct/Nov 2003 after the runs

  5. TPC development since end of 2003 run • 11.10.2003 sensitivity test for 5.3 MeV „Alvarez“ muons: • -5.3kV good for Alvarez μ tracks. TPC tripped at this voltage (= EOR) • mid Oct 2003 TPC moved back to the lab for detailed studies, • a DAQ was setup for automatic voltage setting and controls, • with continuous monitoring of each anode wire and strip cathode • first step: verify the TPC behaviour (TPC unchanged) • - 21.10.-19.11.03 5 bar N2, up to -5.8 kV, later only -5.2 kV • - 25.11.-01.12.03 10 bar H2, up to -5.3 kV, later only -4.8 kV • second step: clean the whole TPC • - 03.12.-18.12.03 clean room: TPC taken apart, all wires inspected, cleaned • - 18.12.-05.01.04 pumping, outgasing 21 10-6 mbar/h  5 10-8/day @10bar • third step: run up the cleaned TPC to reach -5.6 kV stable operation • - 06.01.-23.01.04 10 bar N2, -5.65 kV, HV -35.65 kV (el.Field 2.5 kV/cm) • - 23.01.-11.03.04 5 bar N2, -5.65 kV, HV -35.65 kV • - 15.03.-09.04.04 10 bar H2, around -5.6 kV / -29.6 kV: several hotspots • - 20.04.-30.04.04 10 bar N2, -6.0 kV / 30.0 kV • 30.04.-02.06.04 5 bar N2, -6.1 kV failed, see curves 13/14.05.04 • -6.0 kV / 30.0 kV stable with Sr90 for 2 weeks • - since 03.06.04 10 bar H2, ≥-5.55 kV (status 11.06.04), no hotspots

  6. electronic setup for TPC lab tests Oct-03 up to now

  7. details of TPC test electronics In OLGA lab

  8. TPC inspection during cleaning in Dec 2003

  9. voltage developments and currents during forming in 5 bar N2 (13.-14.5.04) USC (V) IA (nA)

  10. final recovery of TPC voltage to -6.0 kV in 5 bar N2 (14.-16.05.2004)

  11. electronic scheme of hotspot search during TPC tuneup

  12. hotspots seen in 2004 on anode/cathode planes of TPC

  13. for comparison: hotspots encountered during Oct/Nov 2003

  14. electronic scheme of current measurement from Sr90 beta source

  15. currents from Sr90 beta source versus electrical driftfield measured in 5 bar N2 at -5.6 kV

  16. outlook • the PSI TPC is essentially ready to be operated • at -5.4 kV, good for observing „Alvarez“ muons • - PC2 is removed, since it failed in 2003 and an • other geometry was decided for 2004 • - a new entrance flange designed for mounting a • Gatchina Beryllium window will be ready by the • end of June-04 (see design drawing)

  17. new beam entrance flange for Gatchina Be window

More Related