Bez tytulu slajdu

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Physics with the ICARUS T1800 detector
Jan KisielInstitute of Physics, University of
Silesia, Katowice, Polandkisielj_at_us.edu.pl
(on behalf of the ICARUS collaboration)http//www
.cern.ch/icarus/
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Icarus Collaboration
25 INSTITUTIONS, 150 PHYSICISTS
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Scheme of presentation

• Status of the ICARUS detector
• T1800 some numbers
• T1800 physics program
• - nucleon decay
• - atmospheric neutrinos
• - CNGS neutrinos
• - supernova neutrinos
• Summary

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ICARUS Detector
T1800 (T600 T1200) considered in this talk
T600 tested Pavia, 2001
ICARUS T3000
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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,

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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.

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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 lt 50MeV
• from the measurement of the Michel ?
  parameter in µ decay)
• For photons (the p0 mass reconstruction)
  analysis in progress

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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

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Nucleon decay summary table
For the channel
limit is from hep-ex/0502026 (SK), for the rest
from PDG2004.
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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?p? 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
  

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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 ?e events, after solar neutrino and
  KAMLAND results, are of particular interest
  thanks to interferences with the 1-2 mixing
  sector, low energy ?e oscillations should appear
  at some level, even for sin2?130

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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 pelt100MeV/c
• A more precise measurement of the Sub-GeV ?e
  could be the best possible tool to measure ?23
• ? first important insight from ICARUS,
• ? statistical significance from the next
  generation of LAr detectors

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Atmospheric neutrino simulation parameters

• Improved ICARUS simulation
• ? FLUKANUX, 3-flavor neutrino oscillation,
  including matter effects (F.Vissani)
• ? neutrino oscillation parameters
• ?m1228.3 10-5 eV2
• ?m232(1.5) 2.5 (3.4) 10-3 eV2
• sin22?120.825
• sin22?130.140
• sin22?231.0
• dCP0
• exposure 6.36 kton yr (1 yr T600 4 yrs T1800)

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Atmospheric neutrinos event selection

• Separation energy
• ICARUS Sub-GeV ? Evisible lt 1 GeV
• Multi-GeV ? Evisible gt 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

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Atmospheric neutrinos of expected events
255 events
contained events for a 6.36 kton yr exposure
200 events
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Atmospheric neutrinos expected result

• 1s 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

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CNGS neutrinos ?µ and ?e spectra

• new simulation with updated beam parameters
• shared beam mode operation 4.5 1019pot/year,
  with possible upgrade of 50
• beam contaminations
• ?e0.6, ?tlt10-6 (clean ?t appearance)
• possibility of ?µ? ?e search thought the CNGS
  beam is not optimized for such search

?µ and ?e energy spectra with parent particles at
the Gran Sasso site
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CNGS ?µ??t signal vs background
SIGNAL
BACKGROUND
Main part of the background
Flux contamination

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CNGS ?µ??t expected results
CL for the ?µ??t oscillation discovery as a
function of ICARUS exposure.
number of ?µ? ?t events and bkgd for T600(1 yr)
T1800(4 yr) obtained with sin22?231 (in
parenthesis for the 50 upgraded beam intensity)

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Supernova neutrinos

• Assumptions mean energies 11MeV, 16MeV and 25MeV
  for electron neutrino, antineutrino and ?µ/t
  respectively 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 ?13

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Supernova neutrinos T1800 sensitivity

• global sensitivity
• (all reactions)
• up to 1Mly
• distance
• sensitivity to the SN
• direction (elastic
• events only)
• up to galactic SNs

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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 ?t appearance
  and can explore the ?µ??t oscillation
• T1800 can detect SN explosion up to 1Mly distance