300 likes | 634 Views
Large TPCs for HEP ILC-TPC & Fast Neutron detector. Wenxin Wang (D. Attié , P. Colas, E. Delagnes , Yuanning Gao, Bitao Hu, Bo Li, Yulan Li, M. Riallot , Xiaodong Zhang). Self-Introduction. Came from Lanzhou University PhD thesis in Orsay University
E N D
Large TPCs for HEP ILC-TPC & Fast Neutron detector Wenxin Wang (D. Attié, P. Colas, E. Delagnes, Yuanning Gao, Bitao Hu, Bo Li, Yulan Li, M. Riallot, Xiaodong Zhang)
Self-Introduction Came from Lanzhou University PhD thesis in Orsay University Work in RD51 (advisor P. Colas) “Study of large Micromegas detectors for calorimetry and muon detection” 1.2×0.4m2Micromegas prototype Micromegas Digital HCAL W. Wang - FCPPL workshop
Outline • ILC-TPC • 1.1 Micromegas ILC-TPC: • ILC-TPC Large Prototype • Bulk Micromegas with resistive anodes • T2K electronics • Data analysis results • 1.2 Tsinghua GEM-TPC improvement (TU-TPC) • Fast Neutron Imaging Micromegas Detector W. Wang - FCPPL workshop
ILC-TPC1.1 Micromegas ILC-TPC W. Wang - FCPPL workshop
Micromegas Y. Giomataris, Ph. Rebourgeard, JP Robert and G. Charpak, NIM A 376 (1996) 29 MICROMEshGAseous Structure Edrift / Eamplif ~ 1/200 • metallic micromesh (typical pitch 50μm) • sustained by 50-100 μm pillars • Spatial resolution (<100μm) • Time resolution (few ns) • High-rate capability • Good robustness cathode Amplification gap ~50-100 µm ~50 kV/cm Drift gap ~0.3 kV/cm W. Wang - FCPPL workshop
Micromegas TPC: Time Projection Chamber • Ionization energy loss(dE/dx) • 3D track points reconstruction t electrons diffuse and drift due to the E-field Ionizing Particle electrons are separated from ions E B A magnetic field reduces electron diffusion y x Micromegas TPC : the amplification is made by Micromegas Localization in time and position W. Wang - FCPPL workshop
ILC-TPC Large Prototype Design for an ILD TPC in progress 2x80 modules with 8000 pads each Goal: O(200) track points transverse resolution : 100 μm (2 m drift & 3.5 T magnet) . W. Wang - FCPPL workshop
ILC-TPC Large Prototype • Built by the collaboration • Financed by EUDET • Located at DESY:5GeV e- beam • Sharing: • - magnet : KEK, Japan • - field cage : DESY, Germany • - Cosmic trigger : Saclay, France • - endplate : Cornell, USA • Testing: • - Micromegas : Saclay, France, • Carleton/Montreal, Canada • - GEM : Saga, Japan, • Tsinghua, China • - TimePix pixel : F, D, NL TPC ILD W. Wang - FCPPL workshop
Micromegas with Resistive Anode Pad width limits MPGD TPC resolution : pad width 0 : resolution at Z=0 without diffusion resistive foil glue pads mesh mesh B E B E pads Charge dispersion technique with a resistive anode so that wide pads can be used for centroid determination Direct signal readout technique A centroid calculation less precise W. Wang - FCPPL workshop
Micromegas Modules for TPC 2 Resistive Kapton ~3 MΩ/□ Resistive Kapton ~5 MΩ/□ Standard Resistive ink ~3 MΩ/□ W. Wang - FCPPL workshop
T2K Electronics Characteristics • frequency tunable from 1 to 100 MHz (most data at 25 MHz) • 12 bit ADC (rms pedestals 4 to 6 channels) • pulser for calibration • AFTER-based electronics (72 channels/chip) from T2K experiment: • low-noise (700 e-) pre-amplifier-shaper • 100 ns to 2 μs tunable peaking time • Zero Suppression capability • full wave sampling by SCA • Bulk Micromegas detector: 1726 (24x72) pads of ~3x7 mm² W. Wang - FCPPL workshop
T2K Electronics NEW ELECTRONICS – FLAT ON THE BACK OF THE MODULE Goal : Fully equip 7 modules with more integrated electronics, still based on the T2K AFTER chip. First prototype in June 2010 Tests at fall 2010 Then production and characterization of 9 modules in 2011 at the CERN T2K clean room W. Wang - FCPPL workshop
Data Analysis Results W. Wang - FCPPL workshop
B=0 data : Drift velocity measurements Data Analysis Results Drift Velocity in T2K gas compared to Magboltz simulations for - P=1035 hPa - T=19°C - 35 ppm H20 ( T2K gas: Ar:CF4:iso=95:3:2) Vdrift = 7.698 +- 0.040 cm/µs at E=230 V/cm (Magboltz : 7.583+-0.025(gas comp.)) The difference is 1.5+-0.6 % W. Wang - FCPPL workshop
Data Analysis Results • PRF : Pad Response Function • a measure of signal size as a function of track position • relative to the pad • using pulse shape information to optimize the PRF • The PRF: • is not Gaussian. • can be characterized by its FWHM (z) & base Width (z). W. Wang - FCPPL workshop
Data Analysis Results PRF(Pad ResponseFunctions) fits, z ~ 5 cm B=1T data : comparison of resistive ink and Carbon-loaded Kapton W. Wang - FCPPL workshop
Data Analysis Results Position residuals xrow-xtrack W. Wang - FCPPL workshop
Data Analysis Results • MEAN RESIDUAL vs ROW number • Z-independent distortions • Distortions up to 50 microns • for resistive paint • Rms 7 microns for CLK film Z=5cm Z=35cm Z=50cm W. Wang - FCPPL workshop
Data Analysis Results Resistive CLK: 0 =52.7 μm 0 : the resolution at Z=0 Neff : the effective number of electrons W. Wang - FCPPL workshop
Dependence of resolution with data taking conditions Data Analysis Results Resolution at z=5cm (µm) Vmesh (V) W. Wang - FCPPL workshop
ILC-TPC 1.2 Tsinghua GEM-TPC (TU-TPC) W. Wang - FCPPL workshop
Tsinghua GEM-TPC (TU-TPC) Small TU-TPC prototype (GEM-TPC) Total: 99 strips Pitch: 5 mm Strip Width: 2 mm Maximum drift length: 50cm Readout detector: triple-GEM Scheme of TU-TPC prototype W. Wang - FCPPL workshop
Tsinghua GEM-TPC Improvement • Improvement @ TU-TPC • Field cage: single-side strip • to mirror strip: done • Guard ring: adopted • DAQ: from Q, T separately, • to pulse sampling, delayed, • but coming soon • Space charge calculation W. Wang - FCPPL workshop
Fast Neutron Imaging Micromegas Detector W. Wang - FCPPL workshop
Fast Neutron Imaging Micromegas Detector The typical conversion reactions: H(n,n)p 10B(n,α)7Li 6Li(n,α)t α n → t p Scheme of the gadolinium foil (100 μm) etching and image obtained with the Micromegas detector. F. Jeanneau et al. IEEE Transactions on Nuclear Science, vol. 53, issue 2, pp. 595-600 W. Wang - FCPPL workshop
Fast Neutron Imaging Micromegas Detector Readout electronics using AFTER-based electronics (made by Saclay) W. Wang - FCPPL workshop
Fast Neutron Imaging Micromegas Detector PCB design for fast neutron detector ( six T2K front end cards ~2000 pixels 1.5mm ) W. Wang - FCPPL workshop
Fast Neutron Imaging Micromegas Detector • Present - August 2010: Design, construction, transportation and assembly of fast neutron detector; • September 2010: Date taking with fast neutron detector using a 14MeV neutron beam in Lanzhou University. W. Wang - FCPPL workshop
Conclusions Micromegas ILC-TPC: • Since December 2008 , 5 modules of Micromegas TPC have been measured and got good results. The concept isgloballyvalidated. • Next stepwelladvanced : 7 modules to fullyequip the presentendplate. Fast Neutron Imaging Micromegas Detector: We have finished the basic design of fast neutron Micromegas detector and will take data in this year. All these make good preparation for research of neutron imaging. W. Wang - FCPPL workshop
Thank you for your attention And Thanks to all others for the texts and pictures I “borrowed” W. Wang - FCPPL workshop