1 / 33

TIMING COUNTER: status report

This report provides updates on the timing counter (TC) project, including activities such as tests on PM characteristics, Montecarlo activities, and possible new ideas. Preliminary results, tests in a magnetic field, and future plans are also discussed.

csachs
Download Presentation

TIMING COUNTER: status report

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. TIMING COUNTER: status report Giorgio CECCHET, PSI July 11th, 2003

  2. Timing counter • MC activities • Tests on PM characteristics • Preliminary results of May test • Tests in magnetic field • Possible new ideas on “transverse counter”

  3. Montecarlo activities • Reorganization of code repository • Critical revision of TC code • Rievaluation of main geometrical parameters of TC

  4. Length 70 cm Angle (-140,10)° Radius 28.2 0.5 29.0 2.0

  5. Tests on PM characteristics • Basic tests on gain and TTS • Photomultiplier used Hamamatsu fine mesh 1,5”, 19 dynodes H8409-70mod

  6. Serial n. Q.E. % (500nm) VMCP (10^6) Noise (0.5 p.e.) 3256 19,2 2450V 100kHz 7237 18,5 2160V 140kHz MMICRO CHANNEL PLATE PMT Active diameter: 20 mm Test wavelength 670 nm Ligh spot diameter 8 mm

  7. May 2003 test • On May 2003 two scintillators (80x5x1) assembled with 1.5” and 2” PM’s and taken to pE5 area • Aim: measure rough count rate in conditions similar to final

  8. Main results Position similar to final in the Cobra (30 cm off beam axis) Rates: Beam off -> Bck: 25evs/s Beam on, no mu stopper -> 0.5 Mhz Beam on, with mu stopper -> 5 Mhz PMT saturation: 25Hz->10KHz : 1.8 V/pulse 20KHz: 1.7V/pulse 200KHz: 0.4 V/ pulse PMT with higher anode current are nedeed (2” PM better than 1.5”) Need to design a higher current voltage divider?

  9. With collimated beam (10 mm dia.): measure of arrival time differences between 2 PMTs and calculation of time resolution FWHM using the formula: Sigma*2.35/sqrt(2) We obtain 175 ps FWHM for the single PMT, in absence of magnetic field.

  10. Magnetic field tests • One week ago magfield tests started • Conventional magnet in LASA (Milan) with 12 cm headroom and field up to 1.2 Tesla water cooled

  11. Setup used • A very simple setup was used to take the light from a blue diode to the photocathode

  12. New ideas • Investigate the possibility of using a 5x5 mm2 APD from Hamamatsu to readout optical fibers as transverse (trigger) counter. • Few samples made available from PSI and under investigation in Genoa

  13. More work to be done • Complete timing test on single PM in magnetic field • Test scintillator coupled to PM’s in magfield (MARISA) • Full testing of APD’s and optical fibers • Exploit the full capabilities of fine mesh PM’s (new voltage divider?....) • Engineering test of 3-4 scintillators and similar number of fibers during Oct-Nov beam time

  14. B field measurements: planned form july 15 to 30 • Rotable support for 1-2 PMT/MCP for MARISA magnet under construction. • B= 0-1.6 T • Measurement of single PMT parameters (gain/TTS vs B) at different angles with B • 2-PMTs and scintillators assembly.

  15. Not to mention work going on Helium bag!

  16. Schedule • We think now we do not have yet enough infos to make a correct choice of the PM to be used in the TC. We are confident that the new tests will lend us to a reliable decision.

  17. 2002 2003 2004 2005 PMT Evaluation PMT Design Design Manufactoring Assembly Test Milestone

More Related