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Physics with the ICARUS T1800 detector. Jan Kisiel Institute of Physics, University of Silesia, Katowice, Poland kisielj@us.edu.pl. (on behalf of the ICARUS collaboration) http://www.cern.ch/icarus/. L’Aquila, LNGS, Milano, Napoli, Padova, Pavia, Pisa, LNF. ETHZ. Katowice Krakow
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Physics with the ICARUS T1800 detector Jan KisielInstitute of Physics, University of Silesia, Katowice, Polandkisielj@us.edu.pl (on behalf of the ICARUS collaboration)http://www.cern.ch/icarus/ NuFact05, Frascati, 21-26.06.2005
L’Aquila, LNGS, Milano, Napoli, Padova, Pavia, Pisa, LNF ETHZ Katowice Krakow Warsaw, Wroclaw INR UCLA IHEP CIEMAT Granada Icarus Collaboration 25 INSTITUTIONS, 150 PHYSICISTS NuFact05, Frascati, 21-26.06.2005
Scheme of presentation • Status of the ICARUS detector • T1800: some numbers • T1800: physics program • - nucleon decay • - atmospheric neutrinos • - CNGS neutrinos • - supernova neutrinos • Summary NuFact05, Frascati, 21-26.06.2005
T600 T1200 T1200 ICARUS Detector T1800 (T600 + T1200) considered in this talk T600 tested Pavia, 2001 ICARUS T3000 NuFact05, Frascati, 21-26.06.2005
µ+ e+ 18 m 1.5 m Cathode 1.5 m Status of the ICARUS detector • 2001: successful test of the T300 module in Pavia (100 days of data taking, ~29000 triggers on tape, different topologies: long (up 18 m !) muon tracks, hadronic and EM interactions, muon bundles,… NuFact05, Frascati, 21-26.06.2005
Status of the ICARUS detector • 2004: two T300 modules (composing T600) delivered to LNGS, • Construction of next two T600 modules (composing T1200) is now at starting point, • T1800: T600 (1 year of running) +T1800 (4 years of running) considered in this talk. NuFact05, Frascati, 21-26.06.2005
T1800: some numbers • T600 - the instrumented volume: 340.35m3, 476.5 t of LAr, with drift length = 1.5m • T1200 – the instrumented volume: 710.51m3, 994.5 t of LAr, with drift length = 3.0m Energy resolution: • For electrons, Ee < 50MeV: from the measurement of the Michel ρ parameter in µ decay) • For photons (the π0 mass reconstruction) – analysis in progress NuFact05, Frascati, 21-26.06.2005
Nucleon decay: • Full event simulation with FLUKA: Fermi motion of the nucleon inside the Ar nuclei, and nuclear effects due to the scattering or absorption of the decay products inside the parent nucleus are included • Atmospheric neutrinos background evaluation based on a sample corresponding to a 100kton x 1year exposure • Signal/background extraction: sequence of topological and kinematical (total energy, momentum and invariant mass) cuts NuFact05, Frascati, 21-26.06.2005
Nucleon decay – summary table For the channel limit is from hep-ex/0502026 (SK), for the rest from PDG’2004. NuFact05, Frascati, 21-26.06.2005
Nucleon decay: • In all exclusive channels the background is much below 1event/kton/year → discovery capability of nucleon decay with the observation of a single event • SuperKamiokande limits for channels: p→π+ν and n→e-K+ can be improved with the exposure less than one year • The ICARUS T1800 detector has the capability to improve the present limits for several channels of nucleon decay with an exposure of few years NuFact05, Frascati, 21-26.06.2005
Atmospheric neutrino • Studies of atmospheric neutrinos proved the neutrino oscillations and have established mixing parameters of the 2-3 sector of the lepton mixing matrix (Super-Kamiokande), however the precision comes mostly from the systematics, not from the event statistics • Sub-GeV νe events, after solar neutrino and KAMLAND results, are of particular interest: thanks to interferences with the 1-2 mixing sector, low energy νe oscillations should appear at some level, even for sin2θ13=0 NuFact05, Frascati, 21-26.06.2005
Atmospheric neutrino • LAr technique allows to observe all neutrino flavors and both CC and NC events, with reconstruction of complicated event topologies, down to a very low kinematical threshold → for the first time for pe<100MeV/c • A more precise measurement of the Sub-GeV νe could be the best possible tool to measure θ23: → first important insight from ICARUS, → statistical significance from the next generation of LAr detectors NuFact05, Frascati, 21-26.06.2005
Atmospheric neutrino: simulation parameters • Improved ICARUS simulation: → FLUKA+NUX, 3-flavor neutrino oscillation, including matter effects (F.Vissani) → neutrino oscillation parameters: Δm122=8.3 10-5 eV2 Δm232=(1.5) 2.5 (3.4) 10-3 eV2 sin22θ12=0.825 sin22θ13=0.140 sin22θ23=1.0 δCP=0 • exposure: 6.36 kton yr (1 yr T600 + 4 yrs T1800) NuFact05, Frascati, 21-26.06.2005
Atmospheric neutrinos: event selection • Separation energy: ICARUS: Sub-GeV → Evisible < 1 GeV Multi-GeV → Evisible > 1 GeV Super-Kamiokande: 1.33 GeV • Kinetic energy threshold: ICARUS: 10 MeV for electrons and muons Super-Kamiokande: 100 MeV for electrons 120 MeV for single-ring muons 600 MeV for multi-ring muons NuFact05, Frascati, 21-26.06.2005
Atmospheric neutrinos: # of expected events 255 events contained events for a 6.36 kton yr exposure 200 events NuFact05, Frascati, 21-26.06.2005
Atmospheric neutrinos: expected result • 1σ statistical uncertainty (dotted lines) achievable with the expected number of Sub-GeV e-like events in T1800 assuming fit to a flat distribution • 15% excess level (red line) found by the Super-Kamiokande Coll. in their comparison of data with MC NuFact05, Frascati, 21-26.06.2005
CNGS neutrinos: νµ and νe spectra • new simulation with updated beam parameters • shared beam mode operation: 4.5 1019pot/year, with possible upgrade of 50% • beam contaminations: νe~0.6%, ντ<10-6 (clean ντ appearance) • possibility of νµ→νe search thought the CNGS beam is not optimized for such search νµ and νe energy spectra with parent particles at the Gran Sasso site NuFact05, Frascati, 21-26.06.2005
CNGS: νµ→ντ – signal vs background jet jet conservation • Also contribute to background: • from Dalitz • decays • misidentification • as • … jet jet „missing” SIGNAL BACKGROUND Main part of the background Flux contamination NuFact05, Frascati, 21-26.06.2005
CNGS: νµ→ντ –expected results CL for the νµ→ντ oscillation discovery as a function of ICARUS exposure. number of νµ→ ντ events and bkgd for T600(1 yr) + T1800(4 yr) obtained with sin22θ23=1 (in parenthesis for the 50% upgraded beam intensity) NuFact05, Frascati, 21-26.06.2005
Supernova neutrinos: • Assumptions: mean energies 11MeV, 16MeV and 25MeV for electron neutrino, antineutrino and νµ/τrespectively; and the same luminosity for all neutrino flavors, • Number of expected SN neutrino events in ICARUS T1800 for inverted (normal) mass hierarchy and small value of θ13 NuFact05, Frascati, 21-26.06.2005
Supernova neutrinos: T1800 sensitivity • global sensitivity • (all reactions) • up to ~ 1Mly • distance • sensitivity to the SN • direction (elastic • events only) • up to galactic SNs NuFact05, Frascati, 21-26.06.2005
Summary: • T1800 has capability to improve the current limits for several channels of nucleon decay • T1800 allows for almost free from experimental systematics investigation of SubGeV atmospheric neutrinos • T1800 has discovery capability for ντappearance and can explore the νµ→ντoscillation • T1800 can detect SN explosion up to 1Mly distance NuFact05, Frascati, 21-26.06.2005