jhf-kamioka neutrino oscillation experiment using jhf 50 gev ps y.itow icrr,univ.of tokyo jul27,2002...
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JHF-Kamioka JHF-Kamioka Neutrino Oscillation ExpNeutrino Oscillation Exp
erimenterimentusingusing
JHF 50 GeV PS JHF 50 GeV PS Y.Itow Y.Itow
ICRR,Univ.of TokyoICRR,Univ.of TokyoJul27,2002Jul27,2002
ICHEP02 AmsterdamICHEP02 Amsterdam
• Introduction• Facility• Physics goal• Summary
Where we go ?Where we go ?D
isco
very
Ph
ase
K2KThe 1st long baseline experiment
Atmospheric
Discovery of oscillations
mm23232 2 ~ 1.6 – 3.9×10~ 1.6 – 3.9×10-3-3 eV eV22
sin2223>0.92
Solar
Large mixing ine oscillations
mm12122 2 ~ 3 - 20×10~ 3 - 20×10-5-5 eV eV22
sin2212~0.55 - 0.95
Precision study of 3-flavor mixing matrix
Cos
mic
ray
Pre
cisi
on S
tud
y P
has
e A
ccel
erat
or
12, 23, 13
+
m212, m2
23
MNS (Maki-Nakagawa-Sakata) matrix
3 Flavor Mixing 3 Flavor Mixing
3-flavor Oscillation 3-flavor Oscillation
ELmP e /27.1sin2sinsin 213
213
223
2
ELmP x /27.1sin2sincos1 223
223
213
4
Oscillation Probabilities when 213
223
212 mmm
e appearance
disappearance
common
m1
m2
m3
sinsin
2sin
4)()(
)()(
13
122
12
E
Lm
PP
PPA
ee
eeCP
CP in e appearance
StrategyStrategy High statistics by high intensity High statistics by high intensity beam beam Tune ETune E at oscillation maximum at oscillation maximum Narrow band beam to reduce BGNarrow band beam to reduce BG Sub-GeV Sub-GeV beam for Water Cherenkov beam for Water Cherenkov
0.75MW JHF 50GeV-PS
Off-Axis beam Super-Kamiokande
~1GeV beamKamiokaJAERI(Tokai)
0.75MW 50 GeV PS
( conventional beam)
Super-K: 22.5 kt
JHF 0.75MW + Super-Kamiokande
Plan to start in 2007(hep-ex/0106019)
4MW 50 GeV PS
Hyper-K: 1000 kt
Future Super-JHF 4MW + Hyper-K ~ JHF+SK 200
JHF-Kamioka Neutrino ExperimentJHF-Kamioka Neutrino Experiment
OrganizationOrganization
Facility Construction GroupFacility Construction Group Officially formed in KEK on Officially formed in KEK on April, 2001April, 2001 The 3rd physics division, IPNS, The 3rd physics division, IPNS,
Cryogenic facility group, Cryogenic Cryogenic facility group, Cryogenic Science Center, w/ strong support from Science Center, w/ strong support from KEK-PS beam channel groupKEK-PS beam channel group
Experiment working groupDec.1999 : formed (ICRR/KEK/Kyoto/Kobe/Tohoku/TRIUMF)Jun.2001 : Letter of Intent (hep-ex/0106019)Mar.2002 : Meeting to discuss possibility to organize international collaboration
JHF-SK Neutrino Working JHF-SK Neutrino Working GroupGroup
ICRR/TokyoICRR/Tokyo--KEKKEK--KobeKobe--KyotoKyoto--TohokuTohoku--TRIUMFTRIUMF
Y. Itow, T. Kajita, K. Kaneyuki, Y.Obayashi,
C.Saji, M. Shiozawa, Y. Totsuka (ICRR/Tokyo)
Y. Hayato, A.Ichikawa, T. Ishida, T. Ishii, T. Kobayashi,
T. Maruyama, K. Nakamura, Y. Oyama, M. Sakuda (KEK)
S. Aoki, T.Hara, A. Suzuki (Kobe)
T. Nakaya, K. Nishikawa (Kyoto)
T. Hasegawa, K. Ishihara (Tohoku)
A.Konaka (TRIUMF, CANADA)
In addition to the above user group, the neutrino facility construction group is OFFICIALLY formed at KEK.
JHF FacilityJHF FacilityConstruction2001~ 2006 (approved)
(0.77MW)
8 bunches/~5s3.3x1014proton/pulse3.94 (3.64) sec cycle1 yr≡ 1021POT (130 days) Near detectors (280m,2km)
beam-line budget request submitted
Target station
Decay volume
Transport line(Super-cond. Mag.)
OA2°
Osc. Prob.=sin2(1.27m2L/E)
m2=3x10-3eV2
L=295km
osc.
max
.
Off Axis BeamOff Axis Beam(ref.: BNL-E889 Proposal)
TargetHornsDecay Pipe
Super-K.
Quasi Monochromatic Beamx2~3 intense than NBB
Statistics at SK (OAB2deg,1yr,22.5kt)
~4500 tot ~3000 CC e ~0.2% at peak ~102 x (K2K)
Tuned at oscillation maximum
Oscillation probablity
Assume CC Quasi Elastic (QE) reaction
cos
22
pEm
mEmE
N
N
p
ccQE
inelastic
+ n → + p +n
EE reconstruction in water Cherenkov reconstruction in water Cherenkov
+ n → + p
(E , p)
beam energy
ccQEcc-inelastic
DetectorsDetectors
Muon monitors @ ~140mMuon monitors @ ~140m Spill-by-spill monitoring of beam dirSpill-by-spill monitoring of beam dir
ectionection First Front detectorFirst Front detector @280m@280m
Neutrino intensity/directionNeutrino intensity/direction Second Front Detector @ ~2kmSecond Front Detector @ ~2km
Almost same Almost same EE spectrum as for SK spectrum as for SK Water Cherenkov can workWater Cherenkov can work
Far detector @ 295kmFar detector @ 295km Super-Kamiokande (50kt)Super-Kamiokande (50kt)
1.5km
295km
0.28km
Neutrino spectra at diff. dist
dominant syst. in K2K
p
140m0m 280m 2 km 295 km
Far detectorFar detectorSuper-KamiokandeSuper-Kamiokande
( since Apr 1996)
40m
41
.4
m50,000 ton water Cherenkov detector (22.5 kton fiducial volume)
Re-Construction of Super-K Re-Construction of Super-K (Jul 2002)(Jul 2002)
★Precise measurement of neutrino mixing matrix
Accuracy: sin22θ23 ・・・・・・ 1%
Δm223
・・・・・・・・・・ a few %
★Discovery and measurement of non-zero θ13
sin22θ13 ・・・・・・ > 0.006
1st Evidence of 3-flavor mixing !
1st step to CP measurement
Physics Goal Physics Goal
(si
n2 2
)(
m23
2 )
True m232 (eV2)
OAB-2degree,5yr
(sin22)~0.01 (m2) ~<1×10-4
Measurement of sinMeasurement of sin22 2θ 2θ23 , 23 ,
mm222323 disappearance
~3%
m2
sin22
ee appearance in JHF-Kamioka appearance in JHF-Kamioka
e0
Back ground for e appearance search• Intrinsic e component in initial beam• Merged 0 ring from interactions 10% uncertainty for BG estimation
The 1kt 0 data will be studied for exercise
sinsin22221313 from from ee appearance appearance
sinsin222211
33
Background in Super-K Background in Super-K (as of Oct (as of Oct 25, 2001)25, 2001) SignaSigna
llSignal Signal + BG+ BG ee ee totaltotal
0.10.1 12.012.0 10.710.7 1.71.7 0.50.5 24.924.9 114.6114.6 139.5139.5
0.010.01 12.012.0 10.710.7 1.71.7 0.50.5 24.924.9 11.511.5 36.436.4
0.5 sin2213
m2
Off axis 2 deg, 5 years
Off axis 2 deg, 5 yearsat
Sin2213>0.006 C
HO
OZ
exc
lud
ed
Future upgradeFuture upgradeSuper-JHF(4MW)+Hyper-Super-JHF(4MW)+Hyper-
K(1Mt)K(1Mt)
~1,000 kt
Candidate site in Kamioka
Good for atm. proton decay
Sensitivity(3Sensitivity(3) to CP violation (SuperJHF+Hyper-) to CP violation (SuperJHF+Hyper-K)K)
Chooz excluded@m31~3x10-3eV2
>~27deg
>~14deg
Preliminary
4MW,1Mt2yr for
6.8yr for
JHF1 3 discovery
2002 2004 2006 2008 2010
JHF- construction physics run (OAB)
MINOS 2yr
OPERA 5yr
Global ScheduleGlobal Schedule
SKrebuild
SK-half SK-full
SummarySummary Precision study of neutrino mixing matrixPrecision study of neutrino mixing matrix
Next step after the discovery Next step after the discovery We may find a hint for next break-throughWe may find a hint for next break-through
JHF-Kamioka neutrino experiment (2007~)JHF-Kamioka neutrino experiment (2007~) JHF 0.75MW 50GeV-PS+Off Axis beam+Super-KJHF 0.75MW 50GeV-PS+Off Axis beam+Super-K Narrow band beam at oscillation maximum (~ 1GeV)Narrow band beam at oscillation maximum (~ 1GeV) ee appearance, discovery of appearance, discovery of 1313 (sin (sin 1313>0.006,90%CL)>0.006,90%CL) Budget request submitted, R&D startedBudget request submitted, R&D started
Possible upgrade in futurePossible upgrade in future 4MW Super-JHF + Hyper-K ( 1Mt water Cherenkov)4MW Super-JHF + Hyper-K ( 1Mt water Cherenkov) CP violation in lepton sectorCP violation in lepton sector Bonus ! (Proton Decay ! ) Bonus ! (Proton Decay ! )