The J-PARC accelerator complex for rare muon and kaon decays - - PowerPoint PPT Presentation

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The J-PARC accelerator complex for rare muon and kaon decays - - PowerPoint PPT Presentation

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The J-PARC accelerator complex for rare muon and kaon decays particle physics experiments and beamlines accelerator status plan Project X Workshop November 9-10, 2009 Koichiro Nishikawa KEK 1 Status of J-PARC accelerator and slow

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The J-PARC accelerator complex for rare muon and kaon decays

particle physics experiments and beamlines accelerator status plan Project X Workshop

November 9-10, 2009 Koichiro Nishikawa KEK

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Status of J-PARC accelerator and slow extraction

  • 3 major problems before summer
  • Slow extraction

–Spill structure –Beam loss studies just started –May pose severe constraint

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J-PARC Facility (KEK/JAEA）

Bird’s eye photo in January of 2008

South to North Neutrino Beams (to Kamioka)

JFY2009 Beams

30GeV MR Slow Ext. Exp. Facility Materials and Life Experimental Facility

JFY2008 Beams

3 GeV RCS

CY2007 Beams

181MeV Linac

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3 major problems before summer

. t e y d e l l a t s n i t

  • n

t u b , e s a h p t s r i F e s a h p d n

  • c

e S

1 RFQ discharge 2 RF FM core mechanical collapse 3 Power supply ripple

Re Re-

  • entrant

entrant cavity cavity Acceleration Acceleration gap gap beam beam FM core Water cooling Water cooling

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RFQ improvement in last 7 days

Oct Oct ： ：5mA/100 5mA/100μ μs s Nov Nov： ：15mA/200 15mA/200μ μs RCS 120kW equivalent s RCS 120kW equivalent Oct.28 Nov.5

  • Serious discharge problem in RFQ since 2008

– Operation was limited to 5mA/100us (RCS20kW)

  • Various improvements in vacuum in Mar/Jul/Aug,2009
  • Conditioning Sep.~, Beam started Oct.
  • RCS 120kW ~ MR 20-30kW

Tank level , width, Vacuum

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RF core problem

  • Problem has been identified
  • Occurred only for one type of core

– Method of coating and procurement

Collapse Glass cloth separation total cores Already replaced Number of cores of each type

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TIME [ms] AFTER, DECEMBER 2008 TUNE FLUCTUATION BEFORE, JUNE 2008 TUNE FLUCTUATION

Cabling Network improvements

  • K. Sato and H. Toki
  • K. Sato and H. Toki NIM A565(2006) 351, JPSJ Vol.78 No.9(2009

NIM A565(2006) 351, JPSJ Vol.78 No.9(2009) )

Symmetric configuration:

decouple normal and common mode

Same pole connection:

eliminate magnetic field by common mode

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After symmetry After symmetry Q,B Q,B chain chain (10/29) (10/29)

10 100 1000 1E-7 1E-6 1E-5 1E-4

(Iref-Iout)/Iref Frequency [Hz]

10 100 1000 1E-7 1E-6 1E-5 1E-4

(Iref-Iout)/Iref

FFT of P FFT of P-

  • N current

N current

Normal mode Normal mode

Before symmetry Before symmetry (10/8) (10/8)

DCCT DCCT

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Talk by Koseki (accel)

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Moving near to resonance

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Status of slow extraction at MR

Tune change ：± 2.0 E-4 If only due to Q, the stability is ± 1.0 E-5 10 times KEK-PS-MR

0.01 0.02 0.03 0.04 0.05 0.317 0.32 0.323 0.326 0.329 0.332 Slow Extraction @ 2009. 10. 22 Shot #1880 Shot #1881 DCCT

νx (.317 --- .333)

2.33 sec 2.5 sec

Beam Spill 1 Beam Spill 2 MR intensity EQ : Spill structure correction Q-magnet

Need more stability for good spill Quantative studies on beam loss

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Slow extraction summary

Beam loss and spill structure

  • Stabilize power supply

– Symmetric cable configuration (B,Q,S) – Improvement/replace power supply

  • Tune FB/FF

1. 5kW level operation

  • Beam loss studies, spill control

2. 30-50kW

  • Local shielding, radiation maintenance

3. Aim for higher power

  • Idea, R&D
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Slow extracted beam facility (‘hadron hall’)

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J-PARC Facility (KEK/JAEA）

Bird’s eye photo in January of 2008

South to North Neutrino Beams (to Kamioka)

JFY2009 Beams

30GeV MR Slow Ext. Exp. Facility Materials and Life Experimental Facility

JFY2008 Beams

3 GeV RCS

CY2007 Beams

181MeV Linac

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MR

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KOTO experiment

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KL

30GeV proton

sharing the common T1 target

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  • Double collimator system
  • 16o (!) production angle
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10-6 10-7 10-8 10-9 10-10 10-11 10-12 10-13 10-5 BR

SM

Step 1 Step 2 KEK E391a

New Phyics 270kW x 3 Snowmass years

30kW intensity

  • ne month
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  • new beamline
  • Move and modify E391a detector

– CsI calorimeter (KTeV) – readout: waveform digitization – photon veto in the beam

γ γ

a long Japanese musical instrument (zither) with thirteen strings

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(m) Hodoscope +CsI Spectrometer Beam profile Core n

hodoscope + CsI crystals for KL→π+ π- π0 measurement spectrometer for KL→π+ π- measurement

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TREK experiment

A search of T-violating μ polarization in Kμ3

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E06(TREK)

  • New beamlilne K1.1BR

for low-momentum K+

  • SC toroidal spectrometer

(from KEK-PS E246)

  • upgrades with

active muon polarimeter, tracking with GEM

K1.1BR

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J-PARC E06(TREK) for Time reversal violation

  • unique physics reach to new

physics

s µ s µ u ν u ν W H + α γ

http://trek.kek.jp/ T-odd

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Lepton flavor violation

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COMET at J-PARC

฀ μ-e conversion search experiment at J-PARC

  • Target sensitivity ~10-16 (current limit 7x10-13 by SINDRUM

II)

  • SUSY-GUT models predict <10-13

1.17μs (584ns x 2) 0.7 second beam spill 1.5 second accelerator cycle 100ns

nuclei nuclei

μ μ−

− Muon Muon Capture(MC Capture(MC) ) Muon Muon Decay in Orbit (MDO) Decay in Orbit (MDO) SIGNAL SIGNAL

  • Pulsed Proton Beam
  • Beam extinction < 10‐9
  • Large μ yields
  • J‐PARC/MR 50‐60kW
  • π‐capture SC‐solenoid
  • 1011 μ/sec (cf. 108μ/sec at PSI PiE5)
  • Curved‐solenoid detector
  • Lower detector rate
  • Pulsed Proton Beam
  • Beam extinction < 10‐9
  • Large μ yields
  • J‐PARC/MR 50‐60kW
  • π‐capture SC‐solenoid
  • 1011 μ/sec (cf. 108μ/sec at PSI PiE5)
  • Curved‐solenoid detector
  • Lower detector rate

Requirements

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COMET Activity Status

  • Beam Extinction Study

– Abort line measurement

  • This is proved to be due to inefficiency of the chopper (creating empty buckets)
  • Further improvement is expected by using

– Pre-chopper at the Linac, factor of 100 (measurement) – External extinction device, factor of 1000 (simulation)

  • Single bunch, single shot
  • peration of MR
  • Count the number of

protons in the EMPTY bucket in front of a filled bucket

Low gain monitor normal gain monitor Kicker excitation signal Beam intensity monitor

Extinction <2x10‐5 Extinction <2x10‐5

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COMET Activity Status

  • Super-conducting solenoid

– Pion capture solenoid – Design of high Intensity muon beam line

  • B=5T
  • Radiation transparent
  • Technology
  • Detector Solenoid Tech.
  • NbTi+Al conductor
  • Indirect pipe cooling
  • Conductor ordered in Fall 2009
  • Test coil construction and test in 2010
  • B=2T
  • Smaller radiation load
  • Technology
  • NbTi copper stabilized conductor
  • Constructed by arranging coil “pancakes”
  • A new high‐Tc superconductor, MgB2,

will be used for one of the coils for the first time.

  • MgB2 will be used for the electron‐

spectrometer and detector solenoids

basic parameter study by a prototype comprising of 3 pancakes. cooling performance electromagnetic forces between pancakes quench back system

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A possible layout in future

  • Target and beam dump outside the hall
  • Share the upstream proton transport line with the high p beam line
  • External extinction device in the switch yard

23/Oct/2009 ILC Seminar 2009

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New Generation of

Muon g‐2/EDM Measurements @ J‐PARC proposal in preparation

  • Ultra Cold Muon Beam

– σ(pT)/pL < 10-5 ; 106 μ+ /sec – 10 cm spread over 10 km travel – No focusing field needed – No magic momentum or magic everywhere Low momentum (300 MeV/c) Small Magnet (R=33 cm) Strong Filed (B= 3 T)

  • Ultra Precision B Field

– Utilize MRI Technologies

  • Shimming down to local precision of

1ppm (to be compared to 100 ppm in the past )

  • Goals:

– g-2 : 0.1 ppm (E821 0.54 ppm) – EDM : 5 x 10 -22 ecm (1.9 x 10 -19 ecm)

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First look of slow extracted beam by detectors

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KL area

K1.8 area

KLビーム Primary proton beam

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K1.8BR

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Run#26 (Oct.1~Oct.23) MR SX tuning

  • 10/21（wed）
  • ne-shot operation x 4shots
  • 10/22（thur）
  • ne-shot operation

4 x E11 pps 0.2% of design continuous operation 16:00〜07:00 0.17Hz（6 sec cycle） 0.5 x E11 pps

area survey

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Beam Study at K1.8BR/K1.8 on Oct.22

K1.8BR

  • BeamPID Trigger

−1.1GeV/c unseparated beam

p‐bar K− e−

“e−” trigger “K−” trigger “p‐bar” trigger

K1.8

First beam to K1.8

  • beam scan
  • p/π+ separation

+1.1GeV/c unseparated beam

Hit pattern at the beam hodoscope BH1(BS upstream BH2(BS down stream

π+ p

~450ch =11ns

BH1‐BH2 Time of Flight (online)

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First beam to KL Oct.22,23

KL beamline(Aug)

Hut for the beam survey KL beam monitor Extracted beam has spiky structure

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Slow extraction summary

Beam loss and spill structure

  • Stabilize power supply

– Symmetric cable configuration (B,Q,S) – Improvement/replace power supply

  • Tune FB/FF

1. 5kW level operation

  • Beam loss studies, spill control

2. 30-50kW

  • Local shielding, radiation maintenance

3. Aim for higher power

  • Idea, R&D