F. Arneodo Imaging 2003

The ICARUS T600 Liquid Argon Time Projection

Chamber

Francesco ArneodoLaboratori Nazionali del Gran

Sassoon behalf of the ICARUS Collaboration

F. Arneodo Imaging 2003

The ICARUS CollaborationS. Amoruso, P. Aprili, F. Arneodo, B. Babussinov, B. Badelek, A. Badertscher, M. Baldo-Ceolin, G. Battistoni,

B. Bekman, P. Benetti, A. Borio di Tigliole, M. Bischofberger, R. Brunetti, R. Bruzzese, A. Bueno, E. Calligarich,

D. Cavalli, F. Cavanna, F. Carbonara, P. Cennini, S. Centro, A. Cesana, C. Chen, Y. Chen, D. Cline, P. Crivelli,

A.G. Cocco, A. Dabrowska, Z. Dai, M. Daszkiewicz, A. Di Cicco, R. Dolfini, A. Ereditato, M. Felcini, A. Ferrari, F. Ferri, G. Fiorillo, S. Galli, Y. Ge, D. Gibin, A. Gigli Berzolari, I. Gil-Botella, A. Guglielmi, K. Graczyk, L. Grandi, X. He, J. Holeczek, C. Juszczak, D. Kielczewska, J. Kisiel, L. Knecht, T. Kozlowski, H. Kuna-Ciskal, M. Laffranchi, J. Lagoda, B. Lisowski, F. Lu, G. Mangano, G. Mannocchi, M. Markiewicz, F. Mauri, C. Matthey, G. Meng, M. Messina, C. Montanari, S. Muraro, G. Natterer, S. Navas-Concha, M. Nicoletto, S. Otwinowski, Q. Ouyang, O. Palamara, D. Pascoli, L. Periale, G. Piano Mortari, A. Piazzoli, P. Picchi, F. Pietropaolo, W. Polchlopek, T. Rancati, A. Rappoldi, G.L. Raselli, J. Rico, E. Rondio, M. Rossella, A. Rubbia, C. Rubbia, P. Sala, R. Santorelli, D. Scannicchio, E. Segreto, Y. Seo, F. Sergiampietri, J. Sobczyk, N. Spinelli, J. Stepaniak, M. Stodulski, M. Szarska, M. Szeptycka, M. Terrani, R. Velotta, S. Ventura, C. Vignoli, H. Wang,

X. Wang, M. Wojcik, X. Yang, A. Zalewska, J. Zalipska, P. Zhao, W. Zipper.ITALY: L'Aquila, LNF, LNGS, Milano, Napoli, Padova, Pavia, Pisa, CNR Torino, Politec. Milano. SWITZERLAND: ETHZ Zürich. CHINA: Academia Sinica Beijing. POLAND: Univ. of Silesia Katowice, Univ. of Mining and Metallurgy Krakow, Inst. of Nucl. Phys. Krakow, Jagellonian Univ. Krakow, Univ. of Technology Krakow, A.Soltan Inst. for Nucl. Studies Warszawa, Warsaw Univ., Wroclaw Univ.USA: UCLA Los Angeles.SPAIN: Univ. of Granada.

ITALY: L'Aquila, LNF, LNGS, Milano, Napoli, Padova, Pavia, Pisa, CNR Torino, Politec. Milano. SWITZERLAND: ETHZ Zürich. CHINA: Academia Sinica Beijing. POLAND: Univ. of Silesia Katowice, Univ. of Mining and Metallurgy Krakow, Inst. of Nucl. Phys. Krakow, Jagellonian Univ. Krakow, Univ. of Technology Krakow, A.Soltan Inst. for Nucl. Studies Warszawa, Warsaw Univ., Wroclaw Univ.USA: UCLA Los Angeles.SPAIN: Univ. of Granada.

F. Arneodo Imaging 2003

Outline

• The LAr TPC Technology

• The T600 Detector

• Results from the 2001 run in Pavia

F. Arneodo Imaging 2003

Operating principles of the ICARUS LAr TPC:

The technique - IThe technique - I

• ionizing events taking place in a volume of LAr (where a uniform electric field is applied) produce electron-ion pairs• These charges drift along the field lines. The motion of the much faster electrons induces a current on the anode. The electrons can drift several metres if the LAr is highl purified (electronegative impurities < 0.1 ppb O2 equiv.)

F. Arneodo Imaging 2003

The LAr TPC Technology (2)

Ch

arg

e Signals induced

Drift timeA B

C

Ch

arg

e

Drift timeA B

C

Ionizing track

e-

1st Inductionwire/screen grid

2nd Induction wiregrid (x view)

Collection wiregrid (y view)

d

d

p

Non-destructive multiple readout

Continuous waveform recording

Time -- drift

400 ns sampling

Raw Data from a 10 m3 prototype

Scintillation Light

F. Arneodo Imaging 2003

The LAr TPC Technology (3)

• No charge multiplication occurs in LAr• LAr is also a very good scintillator scintillation light (l = 128 nm) provides a prompt signal to be used for triggering purposes and for absolute event time measurement

• High electron mobility (~500 cm2V-1s-1)

• Possibility of extreme purification (<0.1 ppb O2)

Long electron life time (>ms) and drift paths (>m) • High electron-ion pairs yield (~ 10000 e- for 2 mm of a m.i.p. track)

density: 1.4 g/cm3 dE/dx: 2 MeV/c

• Available in large quantities (GAr ~ 0.9% of air)

F. Arneodo Imaging 2003

The T600 Module• Two separate containers

– inner volume/cont. = 3.6 x 3.9 x 19.6 m3

• Sensitive mass = 476 t

• 4 wire chambers with 3 readout planes at 0°, ±60° (two chambers / container)

– ≈ 54000 wires (chann.)

• Maximum drift = 1.5 m

– HV = -75 kV @ 0.5 kV/cm

• Scintillation light readout with 8” VUV sensitive PMTs

F. Arneodo Imaging 2003

LAr Cryostat (half-module)

20 m

4 m

4 m

View of the inner detector

The T600 Module during construction

F. Arneodo Imaging 2003

• Approved and funded in 1996

• Built between years 1997 and 2001

• Completely assembled in the INFN assembly hall in Pavia

• Demonstration test run during first half 2001

– Three months duration

– Completely successful

– Data taking with cosmic rays

• Installation plan in the Gran Sasso underground Lab completed early 2003

• Transportation and installation in LNGS in 2003-2004

The T600 Module

F. Arneodo Imaging 2003

Lifetime evolution during T600 Pavia run

F. Arneodo Imaging 2003

Muon bundle event (Run 699,

Event 48)

T600 Data6 m

F. Arneodo Imaging 2003

3-D reconstruction

F. Arneodo Imaging 2003

e.m + hadron shower

2.2 m

F. Arneodo Imaging 2003

18 m

1.5

m1.5

m

Left

C

ham

ber

Rig

ht

Cham

ber

Cathode

Long longitudinal muon track crossing the cathode plane

Track Length = 18.2 m

3D ViewTop View

dE/dx = 2.1 MeV/cm

3-D reconstruction of the long track3-D reconstruction of the long track

dE/dx distribution along the trackdE/dx distribution along the track

F. Arneodo Imaging 2003

QuickTime™ and aGIF decompressor

are needed to see this picture.

3d reconstruction of a single muon

F. Arneodo Imaging 2003

Air Showerrun 834 ev. 6 right chamber collection view

left chamber collection view

F. Arneodo Imaging 2003

Run 939 Event 95 Right chamberRun 939 Event 95 Right chamber

Te=36.2 MeVRange=15.4 cm

Te=36.2 MeVRange=15.4 cm

Stopping muon reconstruction example

Collection view

Induction 2 view

A

A

B

B

C

C

μ+[AB]→ e+[BC]

µ+

e+

µ+e+

Induction 1 view

F. Arneodo Imaging 2003

-

rays T600 Data

10 MeV3.2 MeV1.8 MeV

Two consecutive

wires

F. Arneodo Imaging 2003

+

e+

e+e- pair

Run 844, Event 24

In-flight annihilation of positron

Collection viewCollection viewInduction 2 viewInduction 2 view

annihilation pointannihilation point

≈20% of positrons from µ decays expected to annihilate before stopping≈20% of positrons from µ decays expected to annihilate before stopping

F. Arneodo Imaging 2003

Physics goals

• atmospheric and long baseline studies

• proton decay

F. Arneodo Imaging 2003

Work is going on:

• Installation at Gran Sasso: tenders, infrastructures, etc.

• Optimization of electronics and trigger

• Analysis (calorimetry, momentum with multiple scattering, muon bundles, scintillation and Cherenkov light)