1 J-PARC and T2K 1.Accelerator construction status and commissioning 2.Accelerator upgrade plan in...

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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)

2

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 )

4

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

5

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

3NBT

3-50BT

MR

MLF

Injection section Extraction section

6

Qx

Qy

(6.35,6.47)

(6.64,6.25)

~3.8x10^11 /bunch (Peak: 22mA, Macro: 0.05ms, Medium: 112ns, Vrf~420kV)~1.9x10^12 /bunch (Peak: 22mA, Macro: 0.05ms, Medium: 560ns, Vrf~420kV)~3.8x10^12 /bunch (Peak: 22mA, Macro: 0.1ms, Medium: 560ns, Vrf~420kV)~4.6x10^12 /bunch (Peak: 22mA, Macro: 0.12ms, Medium: 560ns, Vrf~440kV)

Measured for h=2, 1-bunch op.w/o painting injection

~3.8x10^11 /bunch

~1.9x10^12 /bunch

~3.8x10^12 /bunch

~4.6x10^12 /bunch

“~4.6x1012/bunch; h=2, 1bunch; 25Hz ” operation Successfully performed !!!!!

5Qy=31?

2Qy=13

2Q

x=

13

Q x-Qy=0

Q x-2Q y

=-6

Qx +Q

y =13

corresponding to100 kW in terms of particles per bunch

~6.5% loss near the injection : ⇒ ~0.42kW (assuming 2-bunch op.) <4kW (collimator limit)

Current dependence of the beam loss

H. Hotchi, ATAC2008

7

Summary of Linac/RCS status

• The linac and RCS have been commissioned successfully.• The stability of linac beam is sufficiently good for beam com

missioning of RCS. For RCS:- The optics measurement and its correction were successfully

performed.- The acceleration of 4.6x1012 particles (h=2, 1bunch) with 25

Hz repetition , corresponding to 100 kW operation in terms of particles per bunch, has been achieved.

- The particle loss was almost localized on the collimators.

- The RCS is ready for the MR & MLF beam commissioning- NEXT(Now) : Painting in injection

8

MR (slow cycling Main Ring synchrotron)

RCS

InjectionSlow extraction

Fast extraction

Neutrino beamline

Rf cavities

Beam abort lineHadron Experimental Hall

3-50 BT

To Super-Kamiokande

Ring collimators

BTcollimators

Hadron beamline

Circumference 1567.5 mRepetition rate ~ 0.3 HzInjection energy 3 GeVExtraction energy 30 GeV (start)Superperiodicity 3h 9No of bunches 8 (6 in 2009)Transition j 31.7Transverse emittanceAt injection ~54 mm-mradAt extraction ~10 mm-mrad(30 GeV)

598 ns

58 ns

4.2 s (8 bunches)

4x1013 Protons

9

MR status and commissioning plan

• Installation of accelerator components and vacuum system completed.

• Off beam commissioning has been started in Dec. 2007

• Beam commissioning is scheduled from May 2008.

– 1st stage (May-June 2008): 3 GeV DC opetration

– 2nd stage (Dec. 2007-Feb. 2008): Acceleration to 30 GeV, abort dump, beam extraction to hadron beamline

– 3rd stage (April -June 2009): Beam extraction to neutrino beamline

– 2x1020 protons on the target by the 2010 summer shutdown. ( T2k can search below CHOOZ limit with e-appearance )

10

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

12

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

13

Some experiments at ‘slow extracted beam’

14

Slow Extracted Beam Lines

Handron Hall

Beam Dump

K1.8

K1.8BR

KL

30~50 GeV primary beam

Productiontarget (T1)

K1.8

KL

15

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 →→

17

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

18

-e conversion

Feasibility study•Extinction factor 10-9

•Fast kicker•SC near primary beam

Goal : 5x10-17

Predictions from SUSY Seesaw Models

with upgrade

19

• 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

22

#

295km

23

Super Kamiokande Rebuilt

24

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

25

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.

Narrow intense beam: Off-axis beamOsci. Prob. @m2=3x10-3eV2

f

lux

2.5°3°

E (

GeV

)

1

00 2 8

p (GeV/c)5

Anti-neutrinos by reversing Horn current

26

Main features of T2KThe distance (295km) and m2 (~2.5x10-3 eV2 )1. Oscillation max. at sub-GeV neutrino energy

– sub-GeV means QE dominant• Event-by event Ereconstruction

– Small high energy tail • small BKG in e search and Ereconstruction for osc

illation pattern studies• E(rec.) requirement on e candidates

2. Analysis of water Cherenkov detector data has accumulated almost twenty years of experience

– K2K has demonstrated BG rejection in e search

3. Hadron production measurement (NA61)4. Neutrino interactions at similar energy region (SciBooNE)

27

• Measure prod. from Graphite target• 0-250mrad • 0.5-5GeV/c • K ratio • First data taking in Oct., 2007 (1month)

– Beam: 30GeV proton– Thin target (2cmt 4%int ):~ 500k int.– Replica target (90cm, 80%int): ~180k int.

• Measurements in 2008 planned

CERN-SPS NA61 (SHINE) experiment

T2K goal w/ NA61

(Nbg) for e app. 10% <4%

(sin2223) 1% 0.5%

(m232)[10-4eV2] 1 0.15

28

28

SciBooNE @ FNAL (Jun2007~)SciBooNE @ FNAL (Jun2007~) cross section at sub GeV (~T2

K)• Total collected POT: 1. 46E20

• : 9.2E19 (goal: 1E20)• : 5.4E19 (goal: 1E20)

(from K2K)

(from K2K)

CCQE cand

CCQE cand

Intensive analysis in progres on various modes

29

Beam MonitorProton beam to

Target

NA61K production

distribution

SciBooNENeutrino

interactions

Near detector observables

SKobservables

Fnear(E) Ffar(E)

• Measurements are product of ’s times ’s• K production & neutrino/antineutrino interaction model

30Erec(GeV)

Signal+BGSignal+BG

BGBG

0 1 2 30

10

20

30

40

Sensitivity: Sensitivity: ee appearance appearance

Discovery ofe appearance (,m)

(Pe, e)

E

e

p

e

4

OA2o 5years

m2 = 3x10-3eV2

sin2213 = 0.1

CHOOZ90%

>10 times improvement from CHOOZ

90%CL

31

La Thuile 2004

Measurement of sinMeasurement of sin , , mm

disappearance

m2 = 3.0 x 10-3 eV2

Fully contained , 1-ring, -like sample

# o

f ev

ents

(ar

b.

un

it)

w/o osc.

31

Stat. only

--68%CL (ln L=0.5)--90%CL (ln L=1.36)--99%CL (ln L=3.32)

Goal(sin22)~0.01

(m2)~<1×10-4

(OA2.5(OA2.5))

disappearance

32

Neutrino Beam Line and Near Detector

33

The T2K collaboration thanks CERN for allowing us to re-use UA1 magnet

34

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

35

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

36

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

37

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

38

Target and hornsTarget and horns

38

p beam

3 horns (@ 320kA)

pions

target

To decayvolume

Iron shield

Concreteshield

He vessel

38

1st Horn3rd Horn

Graphite target (26mmx90cm)Day-1 target deliveredHelium gas cooling test successful

Long term test successful @ 320kAHorn1,3 for Day-1 delivered

Target inside Ti-alloy capusule

39

The Neutrino Facility in J-PARCThe Neutrino Facility in J-PARC

39

39

Preparation SectionPreparation Section

SC combined func magsSC combined func mags

Target-Horn SystemTarget-Horn System

Target StationTarget Station

Decay VolumeDecay VolumeBeam DumpBeam Dump

Final Final FocusingFocusingSectionSection

Muon MonitoriMuon Monitoring Pitng Pit

Near Neutrino DetectorNear Neutrino Detector

295km to 295km to Super-KamiokandeSuper-Kamiokande

110m110m

Construction: Apr. 2004 ~ Mar. 2009 (5yrs)

40

Conceptual Design

Engineering Design

Real Production Installation

Proton Beam monitor Feb.~

Superconducting magnets Feb~

Cryogenics Apr~

Normal Conducting magnets

Vacuum system

Target Aug.~

Horn Aug.~

Target Station

Beam Window Jul~

Decay Volume

Beam Dump Aug~

Muon monitor 08/09

Summary of StatusSummary of Status

• All components are in production phase• Installations are starting as scheduled

41

Beyond T2K

1986 Kamiokande

1996 SuperKamiokande K2K and T2K

2009 – MW neutrino beam New Detector

42

CP Violation in Lepton Sector Two approaches

E

LmmUUUU

E

LmmUUUUP

ij

ijjjii

ijjji

iji

2

)(sin)Im(2

4

)(sin)Re(4

22**

222**

CPV sin12 sin23 sin13 m212 (L/E) sin

Solar and Atmospheric

Second Max.

sinsin

2sin

E4

m

)(P)(P

)(P)(PA

13

12212

ee

eeCP

43

First / Second Maximum and

One of the most dangerous bias:Energy mis-reconstruction to lower value than real value

44

CPV in neutrino oscillation

• Depend on the size of different effects from various systematics

– Neutrino-Anti-Neutrino asymmetry

• Cross section, Detection efficiencies

• Ratios e differences

• Contamination of wrong sign

– First vs. Second Maximum

• Wide band beam (small off-axis beam)

• E (L) at the second maximum should be sufficiently large to have reasonable cross section   (E≈0.5 GeV → L≈500km)

• Emeasurement over large range of energy (efficiency for low energy particles)

45

3 sensitivity for CPV in T2K

no BGsignal stat only

(signal+BG) stat only

stat+2%syst.stat+5%syst.

stat+10%syst.

CHOOZ excludedsin2213<0.12@m31

2~3x10-3eV2

T2K 3 discovery

3 CP sensitivity : ||>20o for sin2213>0.01 with 2% syst.

2MW, 1Mt2 yr for

6~7yr for

sinsin

2sin

E4

m

A

13

12212

CP

m212=6.9x10-5eV2

m322=2.8x10-3eV2

12=0.59423=/4

46

Some physics potential studiesSome physics potential studies

Presented by T.Maruyama @ NP08

Presented by K.Kaneyuki @ NP08

100kt Liq Ar TPC @ 660km/0.8deg, 5yr numu 0.54Mt W.C.@295km/2.5deg

SK full det sym w/ 5% syst

No syst, perfect energy reso.

47

SummarySummaryIn one year• J-PARC accelerator complex is being commissioned • Construction of T2K beam line is on time and will be commissioned in

April 2009• Aiming for first results in 2010

In several years• Plan for 1.66MW in 5 years

• T2K data taking which will provide vital information on , needed to define next step,

• Future detector R/D on Mt Water C /~100kt size LiqAr TPC at several candidate sites

Future• CPV in lepton sector and Proton Decay

48

Thank you for your attention

49

50

Primary proton beam linePrimary proton beam line• Superconducting Arc section

– 28 combined function magnets– D2.6T,Q18.6T/m, L=3.3m

• Normal conducting Preparation section and Final focusing (FF) section

– Installation in progress

5050

Tunnel completed (Dec. 2006)

26(/28) mags delivered11(/14) doubles installed

51

Secondary beam lineSecondary beam line

51

3NBT

6m厚コンクリート躯体

ディケイボリューム94m ビームダンプターゲットステーション

He vessel (470t,1000m3) completed, passed vac test in Nov. 2007

Beam dump graphite module being assembled

1/14 part

Sep, 2007

Mar. 2008DV under 3NBT installed in FY2005

52

Beta function and dispersion

: measured from the response

of the closed orbit for a dipole kick (STM)

Injection + Arc

Extraction + Arc

RF + Arc

s(m)

(m

)

Vertical, w/ kick angle corr.Horizontal, w/ kick angle corr.

Good agreement with the design.

181 MeV DC mode

s(m)

x(m

) y

(m)

Design

: Measured from rf-frequency dependenceof the closed orbit

H. Hotchi, ATAC2008

53

Intensity upgrade plan of the first three years 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 1 2 3

LINAC Output power <for RCS> kW 5.4<0.25> 5.4<0.6> 5.4<1.2>6 15 <18>

Peak current mA 5-25

Pulse width msec 50-100 50-250Beam Rep. pps single - 25 single - 25

RCS Output power kW 4 4 4 100 250 (280)(MLF) Typical Beam Rep. pps single - 25 single - 25single - 25

No. of Bunches 1 - 2 1 - 2 1- 2 1- 2 1- 2 2

Particles /bunch for MLF 4.2E11 4.2E11 8.5E11 4.2E12 1.1E13 1.2E13

Particles /bunch for MR (4.2E11) (4.2E11)

Particles /ring for MLF 8.3E12 2.1E13Particles /ring for MR (8.3E11) (4.2E11)

MR Output power kW 0.12 1.2 3.6 100

Energy GeV 3 30

Typical Beam Rep. pps 0.3 0.3 - 0.5

No. of Bunches 1 - 2 1 - 2 6 6

Particles /bunch 4.2E11 4.2E11 4.2E11 1.2E13Particles /ring 8.3E11 8.3E11 2.5E12 7.2E13

HD Output power kW 1.2

Energy GeV 30Particles /burst 8.3E11

NU Output power kW 3.6 100

Energy GeV 30Particles /burst 2.5E12 7.2E13

JFY 2008 JFY 2007 JFY2009

- 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.

54

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

55

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

56

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

13

Small numbers•S31

•sinΦ21 ~ 0.03

mass hierarchy

57

Neutrino beam line with MW protons

57

•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)

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