The ICARUS T600 Liquid Argon Time Projection Chamber

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The ICARUS T600 Liquid Argon Time Projection
Chamber

• Francesco Arneodo
• Laboratori Nazionali del Gran Sasso
• on behalf of the ICARUS Collaboration

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The ICARUS Collaboration
S. 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.
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Outline

• The LAr TPC Technology
• The T600 Detector
• Results from the 2001 run in Pavia

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The technique - I
Operating principles of the ICARUS LAr TPC

• 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 lt 0.1 ppb O2 equiv.)

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The LAr TPC Technology (2)
Non-destructive multiple readout
Raw Data from a 10 m3 prototype
Scintillation Light
Signals induced
Time -- drift
e-
Charge
C
Ionizing track
1st Induction wire/screen grid
Drift time
A
B
2nd Induction wire grid (x view)
d
Charge
C
d
Collection wire grid (y view)
p
Drift time
A
B
400 ns sampling
Continuous waveform recording
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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 (lt0.1 ppb
  O2)
• ?Long electron life time (gtms) and drift paths
  (gtm)
• 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)

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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 _at_ 0.5 kV/cm
• Scintillation light readout with 8 VUV sensitive
  PMTs

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The T600 Module during construction
LAr Cryostat (half-module)
View of the inner detector
4 m
20 m
4 m
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The T600 Module

• 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

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Lifetime evolution during T600 Pavia run
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T600 Data
6 m
Muon bundle event (Run 699, Event 48)
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3-D reconstruction
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e.m hadron shower
2.2 m
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Long longitudinal muon track crossing the cathode
plane
18 m
Right Chamber
1.5 m
Cathode
Left Chamber
1.5 m
Track Length 18.2 m
dE/dx 2.1 MeV/cm
3D View
Top View
3-D reconstruction of the long track
dE/dx distribution along the track
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3d reconstruction of a single muon
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Air Shower
run 834 ev. 6
right chamber collection view
left chamber collection view
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Stopping muon reconstruction example
Induction 1 view
A
µ
B
e
Induction 2 view
C
A
µ
B
e
Collection view
C
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d-rays
?
T600 Data
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In-flight annihilation of positron
20 of positrons from µ decays expected to
annihilate before stopping
Run 844, Event 24
ee- pair
?
e
?
?
Collection view
Induction 2 view
annihilation point
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Physics goals

• atmospheric and long baseline n studies
• proton decay

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Work is going on

• Installation at Gran Sasso tenders,
  infrastructures, etc.
• Optimization of electronics and trigger
• Analysis (calorimetry, m momentum with multiple
  scattering, muon bundles, scintillation and
  Cherenkov light)