Presentation is loading. Please wait.

Presentation is loading. Please wait.

大学 activity: 粒子識別 森 隆志 ( 名古屋大学 ) 関西中部地方 B 奈良女子大学 2009 年 11 月 5 日.

Similar presentations


Presentation on theme: "大学 activity: 粒子識別 森 隆志 ( 名古屋大学 ) 関西中部地方 B 奈良女子大学 2009 年 11 月 5 日."— Presentation transcript:

1 大学 activity: 粒子識別 森 隆志 ( 名古屋大学 ) 関西中部地方 B 奈良女子大学 2009 年 11 月 5 日

2 TOP group, N-lab Contents 1.Introduction 2.R&D of TOP counter components 3.Performance test of prototype 4.R&D of HAPD for A-RICH counter 5.Summary 2 関西中部地方 B 奈良女子大 学 Nov 5, 2009

3 TOP group, N-lab 1. INTRODUCTION 3 関西中部地方 B 奈良女子大 学 Nov 5, 2009

4 TOP group, N-lab 1. Our Motivation Upgrade of Belle PID system  Current PID system of Belle π/K – separation power : 3σ Barrel: TOF + ACC End cap: ACC 4 関西中部地方 B 奈良女子大 学 Target Performance  3σ ⇒ 4σ (0.6 < p < 4 GeV/c) Upgrad e (ACC: Threshold type Aerogel Cherenkov Counter) Barrel: TOP counter End cap: Aerogel RICH Belle-II Current system 2.6m 1.2m e - 8.0GeV e + 3.5GeV 1.5T ForwardBackward Install here Nov 5, 2009 名古屋大学が中心になって 行っている研究について紹介する

5 TOP group, N-lab 2. Principle of TOP counter (1) DIRC (Detection of Internally Reflected Cherenkov light) technique  Cherenkov radiator + screen (photo-detector matrix) Cherenkov light propagate to terminal of quartz with total reflection  Ring image is detect as parabola 5 関西中部地方 B 奈良女子大 学 Imaging with quartz Require large screen For same momentum, velocity β of π/K is different different ring images Nov 5, 2009

6 TOP group, N-lab 2. Principle of TOP counter (2) 6 関西中部地方 B 奈良女子大 学 TOP(Time Of Propagation) counter  Cherenkov radiator + time sensitive screen  Position (x, y) ⇒ Position + time (x, t)  Very compact & simple TOP counter measures TOF + RICH High performance expected! time includes TOF information 1.18m TOF TOP Nov 5, 2009 z y x

7 TOP group, N-lab 3. Expected Performance in Belle-II π/K separation power 4σ for 2

8 TOP group, N-lab Key points  Accuracy of quartz radiator ( = lightguide) Cherenkov light should propagate without distortion and attenuation  Time resolution and sensitivity of photo-detector To obtain clear ring image 4. Typical Ring image & Key Parameters 8 関西中部地方 B 奈良女子大 学 x x z y π/Kπ/K t ~100ps ~1000mm 400mm Top view Detection position & time Typical ring image Important parameters : N det, Nov 5, 2009

9 TOP group, N-lab 5. Requirements to Components Quartz radiator  Propagate Cherenkov light without distortion Flatness : < 100μm Right angle accuracy : ~10”  Total reflection for suppression of attenuation Surface roughness : 5 Å Photo-detector  Single photon detection Gain : ~ 1.0 ×10 6  Important factor of time resolution of TOP counter TTS : σ photodetector < 40ps  Number of detected photon : ~ 20 QE :  Usable in magnetic field of 1.5T for Belle-II 9 関西中部地方 B 奈良女子大 学 Nov 5, 2009

10 TOP group, N-lab 2. R&D OF TOP COUNTER COMPONENTS 10 関西中部地方 B 奈良女子大 学 Nov 5, 2009

11 TOP group, N-lab 1. Surface Test of Quartz 11 関西中部地方 B 奈良女子大 学 single photon mirror prism collimator single photon propagation length[mm] TTS[ps] line ① line ② line ③ ・ 407nm pulse laser ・ Single photon irradiation ・ 47.2°incidence MCP-PMT TTS for each incidence point no degradation of TTS prism quartz MCP-PMT ⇒ sufficiently small roughness Nov 5, 2009

12 TOP group, N-lab 2. Photo-detector Requirements  Gain : 1.0×10 6  TTS : <40ps  QE :  Usable in B -field 12 関西中部地方 B 奈良女子大 学 (Micro Channel Plate) Only photo-detector satisfies requirements MCP-PMT Square type MCP-PMT Co-development with Hamamatsu Photonics Channel ~400  m  ~10  m Channel φ~10μm, Bias angle of MCP : 13°Usable in B-field Nov 5, 2009

13 TOP group, N-lab 3. MCP-PMT R&D Output charge distribution 13 関西中部地方 B 奈良女子大 学 Pedestal Output of single photon Gain ~ 1.0×10 6 Single photon detection OK Nov 5, 2009

14 TOP group, N-lab 4. MCP-PMT R&D 14 関西中部地方 B 奈良女子大 学 検出時間 分布 σ=34.2±0.4ps QE : OK transit time [25ps] counts wavelength [nm] QE[%] TTS < 40ps OK Single photon irradiation Nov 5, 2009

15 TOP group, N-lab 3. PERFORMANCE TEST OF PROTOTYPE 15 関西中部地方 B 奈良女子大 学 Nov 5, 2009

16 TOP group, N-lab 1. Beam Test 16 関西中部地方 B 奈良女子大 学 Detection of ring image Obtain N(  ), number of detected photons par track TTS measurement Items to confirm electron beam ( 2GeV/c ) MCP-PMT Timing Counter MWPC2 MWPC1 Veto counter Trigger Counter TOP Counter Subtract em-shower events Beam trajectory t0 determination Setup of beam test at Fuji test beam line Nov 5, 2009 Performed in Jun. & Dec. 2008

17 TOP group, N-lab 2. Result : ring image Proper action of total system of TOP counter is confirmed 17 関西中部地方 B 奈良女子大 学 ① ② ④ ③ ch Ring image (data) Ring image ( simulation ) transit time[25ps] Nov 5, 2009

18 TOP group, N-lab 3. Result : number of detected photons N(γ) consistency confirmed Slightly different ⇒ remaining shower event 18 関西中部地方 B 奈良女子大 学 Number of detected photons/events arbitrary Nov 5, 2009

19 TOP group, N-lab 1 st 2 nd 3 rd 1 st 2 nd 3 rd 4. Result : transit time distribution We confirmed consistency of transit time distributions for beam test & simulation 19 関西中部地方 B 奈良女子大 学 TTS ( 1 st peak ) Data76.0±2.0 [ps] Simulation77.7±2.3 [ps] Beam irradiation point ( 875mm ) Beam irradiation point ( 875mm ) 875mm 915mm quartz 3 rd 2 nd 1 st ch29 transit time[25ps] [photons] transit time[25ps] カウント数 datasimulation Nov 5, 2009

20 TOP group, N-lab 4. R&D OF HAPD FOR A-RICH 20 関西中部地方 B 奈良女子大 学 2.6m 1.2m e - 8.0GeV e + 3.5GeV 1.5T ForwardBackward Aerogel RICH Nov 5, 2009

21 TOP group, N-lab 1. Aerogel RICH counter 21 関西中部地方 B 奈良女子大 学 Nov 5, 2009

22 TOP group, N-lab 2. HAPD R&D Hybrid structure  Vacuum tube  APD (5x5mm 2 matrix) Bialkali photocathode ~10 4 total gain Confirmed  Single photon detection  Available in 1.5T B-field Current issue  Radiation hardness (neutron) study  Photocathode study Nov 5, 関西中部地方 B 奈良女子大学 73mm Single photon irradiation Photo-detection in Magnetic field

23 TOP group, N-lab 5. Summary & Issues Our Motivation: upgrade of PID system  Target performance: separation power 3σ ⇒ 4σ Idea: barrel ⇒ TOP, end cap ⇒ Aerogel RICH TOP counter  New idea of RICH: Position(x, y) Position(x) + time(=TOF+RICH)  Basic performances are confirmed with prototype  Issue Structure, reconstruction code, lifetime of PMT, readout, etc… HAPD R&D  Performances are available for ARICH  Issue Neutron hardness, high QE photocathode study 23 関西中部地方 B 奈良女子大 学 Nov 5, 2009

24 TOP group, N-lab BACKUP 24 関西中部地方 B 奈良女子大 学 Nov 5, 2009

25 TOP group, N-lab Belle-II experiment Our target of development : Belle-II experiment 25 関西中部地方 B 奈良女子大 学 Belle detector Higher statistics : Higher luminosity ×~40 B-factory ⇒ Super B-factory Higher accuracy : Belle detector upgrade & e + e - asymmetric collider e + : 3.5GeV e - : 8.0GeV e + e - → Υ(4S) → BB π/K-ID is important for flavor tagging Nov 5, 2009

26 TOP group, N-lab History of R&D Butterfly TOP 26 関西中部地方 B 奈良女子大 学 Nov 5, 2009

27 TOP group, N-lab timing 1m assumption Performance Parameterization Important parameters : N det, σ photodetector 27 関西中部地方 B 奈良女子大 学 : Difference of TOF +TOP for π/K (~ 60ps ) : TTS of TOP counter : Detected photons/track (~ 20 ) : TTS of photo-detector (~ 40ps ) : Chromatic dispersion ( 1m propagation in quartz: ~ 50ps ⇒ 25ps ) Can suppress with λ cut filter Separation power : Nov 5, 2009

28 TOP group, N-lab Chromatic Dispersion Chromatic dispersion 28 関西中部地方 B 奈良女子大 学 group velocity of light [m/ns] wavelength [nm] number of detected photons Typical wavelength distribution of detected photons Typical wavelength distribution of group velocity of light Restricts TOP TTS This is because refraction index has wavelength dependence Nov 5, 2009

29 TOP group, N-lab Suppression of Chromatic Dispersion Wavelength cut 29 関西中部地方 B 奈良女子大 学 Group velocity of light Number of Cherenkov photons Transmittance of wavelength cut filter 350nm Suppression of chromatic dispersion with 350nm wavelength cut filter wavelength cut ⇒ TTS improve ⇒ N det decrease fine tune σ chromatic 50 25ps Nov 5, 2009

30 TOP group, N-lab 1. Radiator Quartz (fused silica)  Size : 915×400×20 (mm 3 )‏  Weight : 16kg  Flatness : < 1.2μm/m  Surface roughness : 5 Å  Refractive index : 1.45 Co-development with Okamotokougaku 30 関西中部地方 B 奈良女子大学 Nov 5, 2009

31 TOP group, N-lab Construction of Prototype 31 関西中部地方 B 奈良女子大学 Al honeycomb Quartz Al honeycomb Spring loaded polyathetal head plunger×40/surface Distortion of frame is absorbed by spring Cross section of radiator part 23mm 46 mm  Al honeycomb support Core density : 0.037g/cm 3 – Thickness : 10mm – Surface plate : 0.3mm Al Sag : δ < 80μm  Quartz flatness in Frame <100μm/m (Measured) Readout-box PMT PMT array with λ cut filter Schematic side view of PMT array Joint of 2 parts Optical contact : silicon oil + pressure Nov 5, 2009

32 TOP group, N-lab PMT module HV divider + AMP + Discriminator Small size (28mm W ) Prototype  Fast AMP (MMIC, 1GHz, x20)  Fast comparator (180ps propagation)  CFD with pattern delay Performance  Test pulse ~5ps resolution  MCP-PMT  <40ps Working well comparator amp input low voltage supply to TDC to ADC AMP+CFD 32 関西中部地方 B 奈良女子大学 Nov 5, 2009

33 TOP group, N-lab 2. Performance Confirmation by Beam Test 33 関西中部地方 B 奈良女子大 学 Demonstration of the TOP counter with MCP-PMT array Detection of the ring image of the Cherenkov light Obtain N(  ), the number of detected photons par track Measure the TTS Ring image transit time[25ps] ch Number of detected photons  N det = 16 TTS for 1 st surface of ring image  = 78 [ps] MC simulation Items to confirm Nov 5, 2009

34 TOP group, N-lab Set up for Beam Test 34 関西中部地方 B 奈良女子大 学 electron beam ( 2GeV/c ) MCP-PMT Timing Counter MWPC ② MWPC ① Veto counter Trigger Counter TOP Counter x y x y Subtract em-shower events Beam trajectory t0 determination Quartz + MCP-PMT Fuji test beam line at KEK Nov 5, 2009

35 TOP group, N-lab 35 関西中部地方 B 奈良女子大 学 σ=13.4±0.7ps transit time[25ps] counts TTS of timing counter Nov 5, 2009

36 TOP group, N-lab 36 関西中部地方 B 奈良女子大 学 各伝播距離における測定結果が シミュレーションを再現 伝播距離によって時間分解能はどれだけ悪化する か? 波長分散効果を考慮した理解は正しいのか? 伝播距離によって時間分解能はどれだけ悪化する か? 波長分散効果を考慮した理解は正しいのか? 伝播距離 [mm] 時間分解能 [ps] シミュレーシ ョン 波長分散効果が予想通り のものであることを確認 Nov 5, 2009

37 TOP group, N-lab 37 関西中部地方 B 奈良女子大 学 Nov 5, 2009

38 TOP group, N-lab Summary for TOP Counter TOP counter is very compact & simple detector based on TOF + RICH technique  Radiator propagates Cherenkov light without distortion  Position(x, y) Position(x) + time (= TOF + TOP) Target performance of TOP counter  >4σ for 0.6 < p < 4GeV/c  Key parameters Number of detected photons Prototype of TOP counter has been constructed  We confirmed basic performances of prototype with following parameters: 38 関西中部地方 B 奈良女子大 学 QuartzMCP-PMT Flatness : 1.2 μm/mGain : ~1.0 × 10 6 Roughness : 5 Å TTS : < 40ps Shape accuracy : 10”QE : > 400nm Nov 5, 2009

39 TOP group, N-lab Nov 5, 関西中部地方 B 奈良女子大 学


Download ppt "大学 activity: 粒子識別 森 隆志 ( 名古屋大学 ) 関西中部地方 B 奈良女子大学 2009 年 11 月 5 日."

Similar presentations


Ads by Google