S TATUS OF T HE D UAL P HASE L IQUID A RGON TPC D EVELOPMENTS FOR THE - PowerPoint PPT Presentation

S TATUS OF T HE D UAL P HASE L IQUID A RGON TPC D EVELOPMENTS FOR THE DUNE EXPERIMENT L AURA Z AMBELLI (LAPP - CNRS/IN2P3) on behalf of the collaboration TAUP 2019 - September 11 th 2019 - Toyama

Ti e DUNE experiment DUNE is a long-baseline neutrino future experiment from FERMILAB to SURF [1300km] Aims at measuring (in neutrino and anti-neutrino mode): ⚬ ν μ → ν μ disappearance : Reduce uncertainties on | Δ m 223 | and θ 23 ⚬ ν μ → ν e appearance : Measurement of δ CP and mass hierarchy Far site: Near site: Powerful measure ν fm ux measure ν fm ux ν μ / ν̅ μ after oscillation before oscillation beam ↳ Far detector made of 4 modules of 10kt of liquid argon TPC DUNE Physics - Vol. 1 [1807.10334] 2 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

Liquid Argon TPC technology ⚬ Liquid Argon is inert, dense and naturally abundant. ⚬ Strong electric fj eld applied across the TPC to collect electrons produced by energy loss. ⚬ LAr is transparent to its own scintillation light which can be used as an internal trigger and for complementary calorimetry measurement. — Two LArTPC technologies foreseen for DUNE — Single Phase Dual Phase Anode and Advantages of the dual phase design : Readout ⚬ Charge ampli fj cation in gas Large Electron Multiplier ⚬ Higher signal/noise Gas Extraction ⚬ Lower energy threshold µ Grid ⚬ Fewer readout channels with e- Liquid Argon E e- better resolution e- Cathode ⚬ Accessible cold front end z, time PMT electronics y x DUNE SP Module - Vol. 2 [1807.10327] DUNE DP Module - Vol. 3 [1807.10340] 3 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

Ti e dual phase charge and light signals — Charge signal — Ionization electron are extracted to the gas, Nominal Voltages: Nominal Fields: Anode ampli fj ed in the LEM and 5 kV/cm GAr induced to the collection LEM 33 kV/cm plane on the anode. electro- - l u m i 2. kV/cm n e s Grid c e n c e LAr ionizing particle drift e − — Light signal — From scintillation in LAr [S1] and electro- 0.5 kV/cm - luminescence in GAr [S2]. scint. light + Time constants 128 nm at 6 ns and 1.6 µs. Produced in VUV range, Cathode PMT+TPB has to be shifted to be detected by PMTs 4 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

DUNE FD Module Dual phase LArTPCs for DUNE 2021 ~ … 12m @ SURF 12m 60m 10 kt Long R&D program to develop and optimize the liquid argon dual phase Prototype [protoDUNE-DP] technology towards DUNE scale 2016 ~ 2021 6m @CERN, EHN1 6m 6m Demonstrator R&D 2014 ~ 2017 2010 ~ 2014 m 3 6 × @CERN, Bld 182 6 @CERN, KEK, … × 6 charge readout Today 1m 3m 21 cm drift cage 1m light readout 3 × 1 × 1 m 3 3 ~ 250 L 5 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

Ti e 3 × 1 × 1 demonstrator First large scale LArTPC-DP with 4.2 tons of active volume (3 × 1 × 1 m 3 ) at CERN. Construction started in 2015, and was operated in 2017 for 5 months recording cosmics. → 1 m drift ; 3 × 1 m 2 e - collection area ; 5 PMTs Ti e demonstrator was mainly built for the validation technical aspects of the DP design: ⚬ Construction and operation of stable cryogenic Charge readout plane installation 1m ⚬ Liquid Argon puri fj cation system 3m ⚬ Charge extraction, ampli fj cation and collection 1m on a 3 × 1 m 2 surface ⚬ Stable operation of PMT in LAr 5 PMT ▹ More than 5 × 10 6 cosmic tracks recorded with charge and light signal ▹ Two trigger settings : PMT-self trigger and external trigger with scintillator planes ▹ Many HV con fj gurations explored (at drift, extraction, ampli fj cation and induction fj elds level) 6 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

view 0 [3 × 1 × 1] Event example time view 1 : Reconstructed Track 7 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

[3 × 1 × 1] Preliminary charge analysis [µ-like tracks] — Measurement of the LAr purity through the electron lifetime — dQ/ds [fC/cm] Impurities catches the electron during their drift : View 0 = 4.2 0.2 ms τ ± 40 e N e − ( t ) = N e − (0) × exp( − t/ τ e ) ρ = 0.071 ± 0.003 ppb O2 τ e [ms] ≈ 300 / ρ 0 2 [ppt] 20 A lifetime of ~4ms was measured during all data taking period 0 0 100 200 300 400 500 600 Drift Time [ s] µ — E ff ect of the LEM ampli fj cation fj elds — Arb. Units Amplification Field and truncated mean View 0 1.2 dQ 25.0 kV/cm - = 3.9 fC/cm 〈 〉 ds Ti e charge collected per 1 dQ 26.0 kV/cm - = 5.3 fC/cm 〈 〉 ds 0.8 strip for µ-like tracks dQ 27.0 kV/cm - = 6.0 fC/cm 〈 〉 ds dQ 0.6 28.0 kV/cm - = 8.9 fC/cm 〈 〉 increases with the LEM ds 0.4 ampli fj cation fj eld 0.2 0 (no purity correction) 0 5 10 15 20 25 dQ/ds [fC/cm] 8 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

[3 × 1 × 1] Preliminary light analysis - [S1 signal] — Study of light production — ⚬ Light slow component sensitive to the impurities → Stable value of τ slow measured during 6 months of cryogenic operation [ns] 1600 slow (only runs at null drift fj eld) 1500 τ 1400 1300 Jun 30 Jul 29 Aug 27 Sep 26 Oct 25 Nov 23 — Study of light propagation — ⚬ Quite good agreement between data and out-of-the-box simulation ⚬ LAr Rayleigh scattering length for VUV light is subject to large uncertainties → Our data/MC comparisons prefers: 
 55 cm < λ rayleigh < 163 cm 9 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE


 From the demonstrator to the prototype ▹ Very successful cryogenic operation ๏ LAr level stable at the 50 µm precision ๏ Very good LAr purity through the entire data taking period ▹ Couldn’t run the demonstrator at nominal fj elds due to grid and LEM limitations ๏ Better design of the CRP structure in the prototype ๏ Conservative LEM design option chosen for the prototype 
 6 × 6 × 6 LEM 3 × 1 × 1 LEM 5+10mm 2+2mm 96% active 86% active ▹ Very good performance of the light detection system DUNE baseline Alternative option ๏ Stable low level of PMT noise ๏ No sign of PMT fatigue ๏ Drove the baseline design for DUNE ; 
 alternative options being explored in protoDUNE * : Tetraphenyl Butadiene photocathode TPB* coated ** : Polyethylene naphthalate PEN** sheet above PMT 10 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

Ti e prototype : protoDUNE-DP 4 Charge readout planes [CRP] ⚬ Collection area of 36 m 2 
 e - extraction, ampli fj cation, collection ▻ 1920 × 1920 channels ⚬ Maximum drift length of 6 m 
 ▻ max drift time of 3.7 µs 
 ▻ V cath = 300 kV (500 V/cm) ⚬ 36 PMTs ⚬ Electron lifetime goal at 7 ms 6 m 6 m 6 m outside view (nov. 2017) PMT Layout optimized using light simulations 11 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

[6 × 6 × 6] Construction and preparation (2018-2019) characterization of the CRPs in a cold box End of 2017 cryostat completed fj eld cage mounting CRP installation cathode assembly characterization of the PMTs Ti e cryostat was closed in late march Ti e detector was fully constructed in 15 months ! ‘Cryogenic R5912-20Mod photomultiplier tube characterization for the ProtoDUNE dual phase detector' Belver et al. JINST 13 (2018) no.10, T10006 12 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

[6 × 6 × 6] Charge collection system e − drift e − drift e − drift Due to time constrains, only ) m 2 3 half of the charge × 6 ( P collection area R i n n C o s t n r d could be fully u e m t e n a n r t e e e instrumented a d m Anode only (1 m 2 ) u r (18 m 2 ). t s n i y A 1 m 2 anode only l l u f (no ampli fj cation) 2 area was also mounted. 13 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE

[6 × 6 × 6] Light collection system e − drift e − drift e − drift Cathode and ground grid protection (elevated during PMT installation phase) Light calibration system: external LED source to monitor PMT gain and response over time (one fj ber per PMT) ‘A Light Calibration System for the ProtoDUNE-DP Detector’ Belver et al, JINST 14 (2019) no.04, T04001 14 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE


 
 [6 × 6 × 6] Cooling, fj lling, purifying ⚬ Filling started on July 4 th ⚬ Filling status could be monitored thanks to thermometers and cryo-cameras ⚬ LAr reached its nominal level on August 9 th ⚬ Electron lifetime increases steadily since: 
 → Currently at ~ 500 µs Lifetime [ms] measurement from purity monitors LAr level ⚬ Currently testing each sub-systems individually LAr level meter (16 installed ; 4 per CRP) 15 L. Z AMBELLI - TAUP 2019 - D UAL P HASE LA R TPC FOR DUNE