Information related on experimental proposal for J-PARC


We aim to perform experiments with the K1.8 beam line of the 50 GeV proton-synchrotron facility at J-PARC. The high intensity pion beams by the slow beam extraction will be used. Our subjects are a copious production of the neutron-rich hypernuclei by the double-charge exchange (DCX) reactions (E10) and a detail study on the non-mesonic weak decay in the A=4 hypernuclei (E22).

Proposal status

Proposal submitted

Proposal re-submitted

  • P10-1: Production of Neutron-Rich Lambda-Hypernuclei with the Double Charge-Exchange Reaction ( PDF )
  • P10-2: Exclusive Study on the Lambda N Interaction in A=4 Lambda-Hypernuclei ( PDF )
  • PAC presentation ( P10-1 by A. Sakaguchi, P10-2 by S. Ajimura )

The P10-1 proposal got the stage-1 approval as E10, and the P10-2 proposal also got the stage-1 approval as E22

FIFC meeting in 18/May/07

  • Report on technical issues for E10 experiment ( PDF )
  • FIFC presentation ( PDF )
  • QandA ( PDF )

The E10 proposal got the stage-2 approval.


Beam line

  • Basics of secondary beam line written by Noumi ( PDF partly in Japanese )


  • SksPlus
    • Original design by Takahashi ( PDF in Japanese )
    • Optional designs ( PDF )
  • SPES-II specification ( PDF )


  • Single charge exchange cross section (all in CM)
  • Double charge exchange cross section (all in CM)
  • No charge exchange (NCX) cross section (all in CM)
    • n(K--)Λ ( total, differential )
    • 4He(K--)Λ4He(0+) and 4He(π+,K+)Λ4He(0+) cross section calculated by T.Harada ( PDF )
  • Summary of NCX/DCX cross sections (all in LAB)
    Reactions Elementary Cross Section Hypernuclei Formation
    NCX: (K--) @ 0.9GeV/c 4 mb/sr 0.2 mb/sr
    +,K+) @ 1.05GeV/c 0.5 mb/sr 8 μb/sr
    DCX: (K-+) @ 0.8GeV/c 1 mb/sr n.a.
    -,K+) @ 1.2GeV/c 70 μb/sr 10 nb/sr

LOI related

  • Precise measurement of the non-mesonic weak decay of A=4, 5 Lambda hypernuclei ( PDF )
  • Neutron-rich Lambda hypernuclei by the double-charge exchange reaction ( PDF )
  • High-resolution reaction spectroscopy of S=-1 hypernuclei ( PDF )
  • New generation spectroscopy of hadron many-body systems with strangeness S = -2 and -1 ( PDF )
Layout based on Compass/Autoprefixer/Susy and powered by Lightbox