Status of Liquid Argon TPC R&D (1) 2014/Dec./23, Neutrino - PowerPoint PPT Presentation

Status of Liquid Argon TPC R&D (1) 2014/Dec./23, Neutrino frontier workshop 2014 Ken Sakashita (KEK) R&D collaboration with Iwate University, Yokohama National University and Kure National College of Technology 1. Introduction 2. Development of 2D readout anode board 3. Development of charge readout electronics 4. Plan and summary

Introduction • Liquid argon TPC (LArTPC) - a 3D imaging detector (TPC) with massive target ( ρ =1.4g/cm 3 ) - has a capability of good particle identification and good energy resolution up to several GeV • A large size LArTPC(>20kton) is a candidate of neutrino far detector in a future long-baseline neutrino oscillation experiment and a nucleon decay search experiment Probability of ν μ → ν e @2000km (with different CPV phases) 2000km normal hierarchy 2000km normal hierarchy 2000km inverted hierarchy 2000km inverted hierarchy 0.2 0.2 ) ) e e ! # = 0 deg ! # = 0 deg ν -mode, NH ν -mode, IH " " = -90 deg # # = -90 deg µ 0.15 # = 90 deg µ = 90 deg 0.15 # ! ! P( P( # = 180 deg # = 180 deg MH : large diff. 0.1 0.1 large diff. measurement of between NH/IH @1st peak ν μ → ν e spectrum shape 0.05 0.05 including 1st,2nd osc. peak 0 0 0 2 4 6 8 10 0 2 4 6 8 10 → exploring CPV, MH Energy [GeV] Energy [GeV] CPV : large diff. @2nd peak 2nd peak @ above 1GeV

PMT electornics anode cathode light readout LAr to readout Charged PMT particle Ionization electrons E-field scintillation light Principle of LArTPC Detecting ionization electrons 2D informations at readout plane (anode) with 3~4mm pitch + timing information (z-direction) → 3D track information # of ionization electron from minimum ionizing particle is 1fC/mm (~6000e-/mm) after e-ion recombination(x2/3*) - - - + - + - + No amplification in liquid + + Attenuation during drift due to impurity (O 2 ,H 2 O) : 1/e after 3msec drift (4.8m*) if 0.1ppb impurity → need a high purity LAr for long drift Drift velocity ~1.6mm/ μ sec depending on E-field (*) Diffusion is small (less than 1~2mm after 5m drift) (* in the case of 500V/cm e-field)

Toward a large LArTPC detector • Realization of a long drift length (>5m) is one of key subjects - Long drift → event containment, reduce # of readout channel c.f. ICARUS(300ton) : ~27000ch (1.5m drift, 2x4mx20m anodes) WA105(300ton): ~7680ch (6m drift, 6mx6m anode) • It is important to establish basic technologies: High purity stable long term operation with purity < 0.1ppb High voltage reduce attenuation by increasing drift velocity → more than 250kV (500V/cm) Readout system low noise & high signal gain readout (signal-to-noise ratio > 10)

Ionization PMT PMT light readout LAr to readout electornics Charged particle electrons cathode E-field scintillation light anode How to detect ionization electrons � � single phase+wire readout single phase+pad readout double phase+pad readout � our configuration [ICARUS,US LArTPC] [ETHZ] � � � � � � � � � � � - � � - - + - + - + � � + + � � � � ( μ BooNE case) !"#$ � !"#$%&'()%*#+',-$.#/)-* cosmic μ cosmic μ <5=863):5,@C +>+631:5.,:5,D)1+., x view 300 45= x view y view y view 300 -@C,4,3146E,43,&,=+B1++., Pulse hight [ADC] Pulse hight [ADC] 250 7:>>+63):5,:2 45=,A+1A+5=)68>41,3:, 250 3F+,D)1+,A>45+./ 200 200 01)23,0).3456+,-6*/ 150 150 '& %& !& 100 100 ()*+,- � ./ 50 50 0 0 ! " <5=863):5 0 40 80 120 0 40 80 120 -.*4>>?,@)A:>41/ Drift time [T 0 + μ sec] " Drift time [T 0 + μ sec] # # <5=863):5 300 120 300 -.*4>>?,@)A:>41/ 120 Drift time [T 0 + μ sec] Drift time [T 0 + μ sec] 250 250 $ 200 7:>>+63):5 80 200 80 ->41B+?,85)A:>41/ 150 150 100 7811+53 100 40 40 50 983,:2,;)1+ 50 0 0 ! 0 -50 0 0 32 64 -50 0 32 64 y position [mm] arXiv:1312.6487v1 x position [mm] signal shape is different signal shape is identical between different views among different views low capacitance gain > 15 is obtained thanks to simple detector configuration ICARUS size(4m x 20m) is established double phase amplification

� � � readout Charged electornics to readout LAr PMT light Ionization PMT anode cathode particle E-field electrons light scintillation R&D on 2D anode readout pad • We developed a 2D anode pad 4mm * 16ch - based on PCB technologies (etching) - possible to make a large area board � 4mm * 16ch - 4mm pitch readout (small pads are connected � � along X or Y direction) � � - charge is shared in x and y channel (x1/2) � - charge sharing is confirmed by cosmic data � To connector Total charge in y (arbitrary) 89( 8*( 8:( 8;( To connector <9( <*( <:( <;( - - - + - + =9( =*( =:( =;( - + + + !"%$$ � +9( +*( +:( +;( !"#$$ � !"#$$ � >?@AA(&,-B( 0.8mm pad >?*AA(B&,C' � 0.2mm space Total charge in x (arbitrary) (developed with KEK e-sys group)

A large area 2D anode pad A large area anode pad was also developed for KEK 250L LAr detector based on 50cm x 50cm PCB (largest multilayer PCB in commercially available product) → realize large area by connecting several boards 76cm x 40cm readout test : cosmic ray events [w/ CAEN TPC readout elec.] 40cm 38cm x-z view y-z view 4mm pitch readout Event#1 380ch in total 40cm 76cm x-z view y-z view Event#2 40cm (drift length) ← two example events taken during Nov. ~ Dec ʼ 14 cosmic test (analysis is in progress)

anode cathode readout LAr environment (data) connect to vessel cathode LAr readout electronics anode in cold anode cathode anode connect to directly LAr readout electronics (2~3m) signal cable electronics R&D on readout electronics Developing a low noise readout electronics Placing the electronics as close as possible to the anode to reduce the detector capacitance → small noise Present configuration Possible improvements C cable : 200~300pF - - - - - + - + - - - - - + + + - - + + + - - + + + + + + +

仕様 Development of low-noise and economical electronics 低ノイズ高ゲインの • a front-end (ASIC) chip for low noise × のチップ中に block diagram %;0.,/ =/,0-.>=?( #@AB analog pre-amplifier is developed ($ ($ '3.21 - 8ch pre-amp&shapers in a chip <21.21 - aiming to use in the low temperature ・検出器容量は 100pF までを想定、最小信号 (4fC) に ②出力波形の確認 environment (in first, testing in warm temp.) 対して SN 比が 10 以上のノイズレベル テストパルスを入力し、出力波形を確認、シミュレーションと定性的な比較を行った。 LTARS ASIC chip (2.8mm x 2.8mm) ・プリアンプゲイン 20mV/fC を入力した際の出力波形を以下の図 に示す。 ・電源電圧 ± 2.5V Output signal shape (-20fC input) (developed with KEK e-sys group, one of Open-it projects http://openit.kek.jp) 図 入力の際の出力波形 資料のシミュレーションと比較すると、時定数が少しばかり長いが、波形、振幅など資 料と良く合っている。

• 32ch analog readout board (w/ 4 ASIC chips) is also developed all the measurement done by Y.Iwazaki inputs (from LAr) 2500 (Yokohama National University) Output voltage [mV] 2000 Gain ~30mV/fC 1500 9cm 1000 500 0 0 10 20 30 40 50 60 70 80 outputs Input charge [fC] 12cm (to ADC) ASIC chip ENC ~1100 (~5mV)@C d =100pF Equivalent Noise Charge [electrons] 1200 32 1000 31 Gain [mV/fC] 800 30 ~10% decrease of gain @C d =100pF 600 29 400 28 27 200 26 00 0 20 40 60 80 100 120 20 40 60 80 100 Detector Capacitance [pF] Detector Capacitance [pF]

LAr readout electronics anode cathode vessel connect to New readout system ボード連結テスト 32ch analog board digital board • A new digital board is developed - it enables to make a compact readout system 1. 治具の作成 32ch differential inputs (2Vpp) 2. テスト環境構築 12bits FADC (10~40MSPS) Readout boards 3. テストパルス確認 Airtix-7 FPGA Ethernet (RJ45 or SFP) 4. ノイズ確認 directly connect to vessel ! NIM-in 4ch, NIM-out 1ch size: 9cm x 14.5cm Ethernet for DAQ (SiTCP) - - - + - + - + ~30cm + + External trigger input

electronics readout Cosmic test • Performance of the new electronics has been evaluated based on cosmic muon signal of LAr a small LAr detector (6.4cm x 6.4cm readout plane) cosmic μ Trigger Scint. 2D anode anode 2D grid anode field Trigger Scint. shapers 5.5 cm cathode 6.4cm (anode area)