1 / 14

Study of a charge distribution on a readout board with a triple GEM chamber

Study of a charge distribution on a readout board with a triple GEM chamber. Shoji Uno (KEK) KEK Detector Technology Project October 31 st , 2006. MPGD group T. Uchida, M. Sekimoto, T. Murakami, M. Tanaka, S. Tanaka, N. Ujiie, and K. Nakayoshi (KEK)

brady-logan
Télécharger la présentation

Study of a charge distribution on a readout board with a triple GEM chamber

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. Study of a charge distribution on a readout board with a triple GEM chamber Shoji Uno (KEK) KEK Detector Technology Project October 31st , 2006 MPGD group T. Uchida, M. Sekimoto, T. Murakami, M. Tanaka, S. Tanaka, N. Ujiie, and K. Nakayoshi (KEK) K. Kadomatsu and A. Sugiyama (Saga University ) E. Nakano and S. Nakagawa (Osaka City University)

  2. Contents • GEM foils made by Japanese company • Effective Gas gain as a function of various parameters • DVGEM, ED, ET,EI, gI • Gas mixture: Ar-CH4(90/10) (P10) Ar-CO2(70/30) • Charge distribution on a readout board

  3. 10cm 10cm GEM foils made by Japanese company • New method (plasma etching) was tried in a few years ago. • Not chemical etching (CERN) • M. Inuzuka, et al., NIM A 525(2004) 529-534 • Plasma + Laser • To reduce sparks • It is convenient for us to make new types of GEM foils. • Fine pitch/small hole : 50mm/30mm • Thicker/thinner : 100(150)mm/ 25mm • Other activities in Japan • Univ. of Tokyo • RIKEN • etc • Today, I will report on results with standard GEM foils. • 50mm thick • 140mm pitch 70mm diameter Scienergy Co., Ltd. (Japanese company) http://www.scienergy.jp/

  4. Chamber Structure 55Fe (5.9 keV X-ray) Cathode Drift region 0.5kV/cm gD ( 4 mm) GEM1 Transfer1 region 1.75kV/cm gT1(2 mm) GEM2 Transfer2 region 1.75kV/cm gT2(2 mm) GEM3 Induction region 3.5kV/cm gI(1 mm) Strip Ar-CO2 ΔVGEM＝370V P10 ΔVGEM＝330V

  5. P10 Ar-CO2 Effective gas gain vs ΔVGEM

  6. Gas gain vs various parameters P10 Ar-CO2 P10 Ar-CO2 EI ED Ar-CO2 P10 Ar-CO2 EI ET

  7. 100mm Zoom up view Readout strip 100mm • Readout strip • Strip pitch ： 200 mm • width　　　 ： 100 mm • gap　 ：100 mm • length : 50mm • Number of strips = 64 200mm

  8. Read out system CAMAC System Pulse Trans. Gate Gen. RPN220 CCNET GATE Foil BUSY GATE 0.5 m GATE Belle-CDC Pre-amp. VETO 120 μs delay Disc. RPN220×４ Strip GATE 30 m Fanin Fanout Belle-CDC Pre-amp. ×4 ADC 2249W×６

  9. OneEventDisplay ADC ADC 63 0 63 0 Channel Channel

  10. Charge distribution ADC SUMADC P10 s = 359.7±0.4 mm ΔVGEM＝330V Ed= 0.5 kV/cm Et=1.65 kV/cm Ei= 3.3 kV/cm Ar-CO2(70/30) s = 181.2± 0.3 mm ΔVGEM＝370V Ed= 0.5 kV/cm Et=2.59kV/cm Ei=5.18 kV/cm -1 0 1 -1 0 1 dX（each strip－COG) ｍｍ Triple GEM gD, gT1, gT2, gI=1.5, 1, 1, 1mm

  11. Measurement results s for a gauss fit in a charge distribution Unit : mm Total gap : gD/2 + (gT1+ gT2 ) + gI

  12. Data MagBoltz P10 s2 (mm2) Ar-CO2

  13. MagBoltzvs.Measurement Data Data MagBoltz P10 Ar-CO2 Electric field in transfer region (kV/cm)

  14. Summary • Japanese company can produce GEM foils with new methods ( Plasma or (and) Laser ). • GEM chamber has been constructed and tested. • Effective gas gain was measured for various parameters. • Charge distribution was measured. It is consistent with naive estimation from diffusion without GEM structure.

More Related