1 J-PARC and T2K 1. Accelerator construction status and commissioning 2. Accelerator upgrade plan in first 5 years 3. Experiments with slow extracted beam 4. The T2K experiment 5. Possible future experiment 6. Summary IV International Workshop on: “Neutrino Oscillations in Venice” April 18, 2008 Koichiro Nishikawa (KEK)
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1 J-PARC and T2K 1.Accelerator construction status and commissioning 2.Accelerator upgrade plan in first 5 years 3.Experiments with slow extracted beam.
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J-PARC and T2K
1. Accelerator construction status and commissioning
2. Accelerator upgrade plan in first 5 years
3. Experiments with slow extracted beam
4. The T2K experiment
5. Possible future experiment
6. Summary
IV International Workshop on: “Neutrino Oscillations in Venice”
April 18, 2008Koichiro Nishikawa (KEK)
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Materials and Life ScienceExperimental Facility
Hadron Beam Facility
Nuclear Transmutation
J-PARC
J-PARC = Japan Proton Accelerator Research ComplexJoint Project between KEK and JAEA
3 GeV Synchrotron(25 Hz, 1MW)
Linac
(350m)
50 GeV Synchrotron
(0.75 MW)
500 m
Neutrino to Kamiokande
Slow Extracted Beam Facility
3
Linac
SDTL
Ion source, LEBT, RFQ, MEBT(2 choppers, 2 bunchers)
Not funded Second phase
DTLFront-end part
• Particle: H-
• Energy: on day-one 181 MeV with ACS 400 MeV • Peak current:
at 181 MeV 30 mA at 400 MeV 50 mA • Repetition: 25 Hz • Pulse width: 0.5 msec
Commissioned Jan.2007 upto SDTL ( 181 MeV )
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Excellent stability of LINAC
Parameter Unit Design Commissioninggoal *
Achieved to date
Output energy MeV 181 181 181Peak current mA 30 25 25 30 (RFQ)Linac beam power kW 36 1.2 1.2 (w/o chop)Momentum spread % < ± 0.2
includig jitter< ± 0.2includig jitter
25 mA:0.16 (FWHM)
Orbit distorsion mm ± 1 ± 1 ± 1Beam position jitter mm ± 0.1 ± 0.1 ± 0.2**Peak current fluctuation % ± 1 ± 1 ± 1***
Values in gray are preliminary.
** During several hours.*** During several hours. With the peak current and pulse width of 25 mA and 0.25 ms,
* Corresponding to 20 kW beam power from RCS
M. Ikegami, ATAC2008
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Status of RCS (Commissioned Nov 2007)
Collimator section
RF section
Beam injection section
Circumference 348 mRepetition rate 25 HzInjection energy 181/400 MeVExtraction energy3 GeVHarmonic number 2
RF section
from Linac to MLF
RCS
to MR
1st arc sectionTwo beam transport lines
3NBT:transport line to the MLF3-50BT: transport line to the MR
– 2x1020 protons on the target by the 2010 summer shutdown. ( T2k can search below CHOOZ limit with e-appearance )
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Intensity Upgrade
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• Space charge limit Make larger phase space in RCS RF bucket Single bunch operation - longer bucket• Cycle time Faster acceleration with more RF power
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Power Upgrade of Neutrino Beam (8 bunches/pulse)
MR 30 GeV
LINAC 181MeV
Cycle time 3.52 sec
4 1013 P/bunch
0.27MW
RCS h=1 Operation
Cycle time 1.92
8.3 1013 P/bunch
1MW
0.91MW
MR 30 GeV
LINAC 400MeV
Cycle time 1.92sec
8.3 1013 P/bunch
1.66MW
MR RF Upgrade
Cycle time=1.76
0.55MW
5% 8% 17%
( MR usage of RCS)
LINAC 400MeV
0.45MW
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Some experiments at ‘slow extracted beam’
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Slow Extracted Beam Lines
Handron Hall
Beam Dump
K1.8
K1.8BR
KL
30~50 GeV primary beam
Productiontarget (T1)
K1.8
KL
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E05 Hyper nucleiNo.1 priority in nuclear physics
2 MeV FWHM resolution
~6 events/day/MeV for 50 msr,
2g/cm2-thick Pb ~20 days
1616
Measurement of KMeasurement of KL L →→
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E14 • Step 1
– Goal: First observation of the decay– Upgrade KEK E391a detector– New CsI (FNAL) calorimeter– 160 production angle (small neutron halo)– Beam survey in 2009
• ( Step 2: >100 events to measure the BR )
10-6
10-7
10-8
10-9
10-10
10-11
10-12
10-13
10-5
BR
Standard ModelStep 1
KEK E391a Run2
New Physics
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-e conversion
Feasibility study•Extinction factor 10-9
•Fast kicker•SC near primary beam
Goal : 5x10-17
Predictions from SUSY Seesaw Models
with upgrade
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• Current result is 3.4 sigma above from the SM value
• Efforts toward a proposal have started to realize the experiment in the earlier phase of J-PARC– Technical feasibility of bunch s
equences and beamline are being explored
– Harmonics changes in the MR and kicker design are key issues
– KEK designed new inflector for a better muon injection eff.
– g-2 ring to be shipped from BNL
Muon g-2@J-PARC
20List of ExperimentsMany nuclear physics experments
2121
T2K Collaboration~400 members from 12 Countries
Canada, France, Germany, Italy, Japan, Korea, Poland, Russia, Spain, Switzerland, UK, US
• High intensity beam (~102xK2K) from J-PARC MR• Discovery of e appearance Determine 13
• Precision meassurement of disappearance 23, m232
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#
295km
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Super Kamiokande Rebuilt
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100
0
0
0
010
0
0
0
001
1212
1212
1313
1313
2323
2323
321
321
321
cs
sc
ces
esc
cs
sc
UUU
UUU
UUU
Ui
ieee
0.68<sin2212<0.94 sin2 2sin2 2
Lepton mixing pattern ?
0 1.0
90% CL allowed values
sin22 13sin2sin2
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TargetHornsDecay Pipe
Super-K.
decay Kinematics
OA3°
OA0°OA2°
OA2.5°
Statistics at SK (OAB 2.5 deg, 1 yr, 22.5 kt)
~ 2200 tot ~ 1600 CC e ~0.4% at peak
Quasi Monochromatic Beam x 2~3 intense than NBBFairly independent on spectrum dist.
The T2K collaboration thanks CERN for allowing us to re-use UA1 magnet
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Having been transported by lorry to Geneva La Praille and loaded onto freight trains that took them to the port of Antwerp (Belgium), the containers are now aboard container ships bound for Pusan in South Korea, from whence they will sail to the port of Hitachinaka, their point of entry to Japan.
Sailing... and has arrived at J-PARC site
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Status of 280m Near DetectorsStatus of 280m Near DetectorsOn-axis detector(INGRID)
Iron+ScibarSandwich
In production, ready in Apr.2009
UA1 magnetbeing shippedInstalled in Apr-Jun.2008
Photo-sensor (~60k ch) in production TPCECAL
FGD
FGD
All are in production
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MW Neutrino Beam Line
• Heating by dEdX
– Water cooling and He cooling (where possible)
• Shock wave and high radiation
– Remote handling
– Graphite for target and dump core (< 10ppm O2)
– Tritium, NOx production
– Minimum number of beam windows
One piece enclosure from entrance to the target area to beam dump, filled with He
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37
p beam
horns
pions
target
To decayvolume
Iron shield
Concreteshield
He vessel
Target StationTarget Station
• Installation of the helium vessel(~470ton, 1000m3) finished, passed vacuum test in Nov. 2007 as scheduled
- Requirement from T2K: 2.0E20 protons on the target by the 2010 summer shutdown. - Guideline :Beam loss at each extraction point < 25 -100 W to keep residual radiation level < 1mSv/h.
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First high enrgy MW fast-ext’ed beam !
cm
cm
1100o
(cf. melting point 1536o)
3.3E14 ppp w/ 5s pulse
When this beam hits an iron block,
Material heavier than iron would melt.
Thermal shock stress
(cf. 耐力 ~300 MPa)
Material heavier than Ti might be destroyed.
Cooling power and radiation shield 12GeV PS x 100
GPaTE 3
Residual radiation
> 1000Sv/h
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Present Technology limit
• Temparature rise and thermal shock limit us about 2MW proton beam
– Alminum horn – Graphite target beam power
– Ti vacuum window number of protons
• Substantial R/D and experiences needed to go substantially beyond this limit
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31322
132
232
132
13
212
13231223122
132
232
122
232
122
132
12
21313223131223122
13
21313223131223122313122
13
3122
232
132
13
sincos4
)21(8
sin)cos2(4
sinsinsinsin8
sinsincos)cos(8
sin4)(
E
aLSSSC
SSSCCSSSCCCS
SSSCCC
SSSCCSSSC
SSCP e
seigenvalue mass: ,
energy, neutrino: length,flight :
,4/
222
2
ijiij
ijij
mmmm
EL
ELm
Sij=sinij, Cij=cosij
e appearance probability
LE
L
GeV
E
cmgE
aL
2~
4][]/[6.7
4 3
CP conserving
CP
solar
matter effect
-, a -a for e
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Small numbers•S31
•sinΦ21 ~ 0.03
mass hierarchy
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Neutrino beam line with MW protons
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•Shock wave
•Heat generation •Various sources including dE/dX 4kW(water), MW (air)
•magnets and their power water cooling•Target Horn TS-DV-BD wall /BD core water cooling
•Radioactive water and air•radioactive water 13GBq / 3weeks (must be diluted <30Bq/cc to dispose)
many tanks, ion exchange filter, backup loop radioactive He 7GBq / 3 weeks (must be diluted <5mBq/cc to dispose) Production cross section of Tritium in He is 1/10 of air He vessel ( need O2 <10ppm)