IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting The preliminary results of MPGD-based TPC performance at KEK beam test Yukihiro Kato Kinki University (ILC-TPC Collaboration)

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Motivation Comparison of several readout scheme (gas amplifiers) using same Field Cage, Electronics, analysis procedure, MWPC: beam test in Jun GEM: beam test in Apr. 2005, Oct MicroMEGAS: beam test in Jun. 2005, Oct 2005 Understand the basic performance of MPGD-based TPC Results are updated from ACFA05

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting ILC-TPC collaboration Asia Japan (KEK, Saga, Tokyo A&M, Tsukuba, Kogakuin, Kinki, Hiroshima) Philippines ( MSU-Iligan ) Europe Germany ( DESY, MPI ) France ( CEA Saclay, LAL Orsay, IPN Orsay ) North America Canada ( Carlton, Montreal )

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting KEK PS beam line π2 beam line: π +, π ‐, p (P = 0.6 ～ 4 GeV/c)

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting π2 beam line

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting PC-MAG known as JACCEE magnet for BESS-II B field ： 1 ～ center, No Return Yoke inner diameter: 850 mm, effective length: 1000 mm Transported to DESY for EUDET at Dec. 2006

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting MP-TPC Pad plane: effective area 75×75 mm 2 Maximal drift length: 260 mm Detachable endplate MWPC and MPGD (GEM, MicroMEGAS) Field Cage Preamplifiers Readout plane

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting GEM (Gas Electron Multiplier)  Two copper foils separated by kapton (polymide), multiplication takes place in holes, uses 2 or stages for safer operation.  High electric field inside the holes CERN GEM geometry  Copper electrodes (5μm thick)  Kapton insulator (50μm thick)  Bi-conical holes due to chemical etching  Hole size D ～ 60 μm, pitch p ～ 140μm  Using 3 stages induction gap: 1.0mm, transfer gap: 1.5mm

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting MicroMEGAS Mesh size: 50μm Micromesh sustained by 50 μm pillars, multiplication between anode and mesh, one stage Self-suppression of positive ion feedback 50μm line of electric force pillar

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Readout scheme and Gas DAQ electronics: ALEPH TPC electronics ・ Charge sensitive pre-amp+shaper amp (500ns) ・ 8-bit FADC with 12.5MHz sampling rate B field: 0, 0.5, 1.0 Tesla Readout Device Pad Size (pitch)GasDrift field GEM (triple GEM) 1.17mm ×6mm (1.27mm ×6.3mm) TDR: (Ar:CH4:CO2 = 93:5:2) P5: Ar-methane (5%) 220V/cm 100V/cm MicroMEGAS 2mm ×6mm (2.3mm ×6.3mm) Ar-isobutane (5%)220V/cm MWPC 2mm ×6mm (2.3mm ×6.3mm) TDR220V/cm

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Typical event (MicroMEGAS, B=0.5T)

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Pad-response per region MicroMEGAS, Ar-isobutane (5%), B=0.5T, E = 220 V/cm z = 0 mm z = 260 mm the avalanche charge spread for single electron

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Pad-response per region GEM, TDR, B = 1T, E = 100V/cm z = 0 mm z = 260 mm

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Transverse diffusion properties B (Tesla)Diffusion constant (C D )C D by Magboltz simulation 0480± ± ± ± ± ±88 preliminary result diffusion in readout MicroMEGAS

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Transverse diffusion properties GEM B=1T Gas TDR (E=220V/m) P5 (E=100V/m) CDCD 213.0± ±0.4 C D [ Magbolz ] ±3 502±2 TDR P5 preliminary result

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Spatial resolution vs. drift distance  C D : diffusion constant from data  σ 0 : resolution without diffusion  N eff : effective number of electrons diffusion other effects

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Spatial resolution MicroMEGAS preliminary result B 0 T 0.5 T1.0 T N eff 15.1± ± ±7.7

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Spatial resolution GEM TDR N eff = 21.4±0.3 P5 N eff = 23.0±0.7 preliminary result

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Analytic formula for spatial resolution [A] Finite pad pitch: rapidly disappears as z increases. N independent. [B] Diffusion, gas gain fluctuation, finite pad pitch term: scales as 1/Neff, for δ function like PRF asymptotically: [C] Electronic noise: z independent

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Comparison with measurements Formulation can explain the MicroMEGAS data.

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting diffusion and resolution MicroMEGAS GEM MWPC Gas Ar-isobutane (5%) TDRP5TDR 723±88432±2502±21270±4 CDCD 195± ± ±0.4211±1 C D [Magboltz] N eff 16± B = 1T data preliminary results

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Summary The values of diffusion constant (C D ) are consistent with Magboltz simulation. In the case of MicroMEGAS, σ PR 0 has a large error. It is much smaller than the pad pitch. Need to spread the avalanche size by resistive foil, etc. Spatial resolution can be described with the simple analytic formula.

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting Backup slide

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting K.Fujii

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting K.Fujii

IHEP, Bejing 9th ACFA ILC Physics and Detector Workshop & ILC GDE Meeting K.Fujii