Re-measurement of the 4He(8He,8Be) reaction

ORAL

Abstract

 The 4He(8He,8Be)4n reaction has been measured again at 186 AMeV for studying the 4n system (tetra-neutron). interest on the tetra-neutron system was attracted by a candidate resonance in ref. [1].  A new measurement with higher statistics and better accuracy are anticipated for more detailed study of the tetra-neutron system.

 The intensity of the 8He beam was approximately twice that in the previous experiment (3.5 × 106 cps at the target). For the absolute calibration of the missing-mass, we measure the 1H(3H,3He) reaction at 310 AMeV without changing the settings of the beamline magnets and the SHARAQ spectrometer, since the magnetic regidities of the 186 AMeV 8He and the 310 AMeV 3H are the same. In the preliminary result,  the accuracy of the excitation energy of 4n is evaluated to be approximately 100 keV.

  In this contribution, we will report the current status of the data analysis of the present experiment for understandings of the tetra-neutron system.

[1]: K. Kisamori et al., Phys Rev. Lett. 116, 052501 (2016).

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Presenters

  • Shoichiro Masuoka

    Center for Nuclear Study, University of Tokyo, RIKEN, Toho, Osaka, TITech, Miyazaki, LPC Caen, Tokyo, Center for Nuclear Study, the University of Tokyo

Authors

  • Shoichiro Masuoka

    Center for Nuclear Study, University of Tokyo, RIKEN, Toho, Osaka, TITech, Miyazaki, LPC Caen, Tokyo, Center for Nuclear Study, the University of Tokyo

  • Susumu Shimoura

    Center for Nuclear Study, the University of Tokyo

  • Motonobu Takaki

    Center for Nuclear Study, the University of Tokyo

  • Shin'ichiro Michimasa

    Center for Nuclear Study, the University of Tokyo, Center for Nuclear Study, University of Tokyo, CNS, Univ. of Tokyo, CNS, University of Tokyo

  • Shinsuke Ota

    Center for Nuclear Study, the University of Tokyo

  • Masanori Dozono

    Center for Nuclear Study, the University of Tokyo, Center for Nuclear Study, The University of Tokyo

  • Chihiro Iwamoto

    CNS, University of Tokyo, Center for Nuclear Science, University of Tokyo, Center for Nuclear Study, the University of Tokyo

  • Keita Kawata

    Center for Nuclear Study, the University of Tokyo

  • Noritaka Kitamura

    Center for Nuclear Study, University of Tokyo, Center for Nuclear Study, the University of Tokyo, CNS, the University of Tokyo

  • Motoki Kobayashi

    Center for Nuclear Study, the University of Tokyo

  • Ryo Nakajima

    Center for Nuclear Study, the University of Tokyo

  • Hiroshi TOKIEDA

    Center for Nuclear Study, the University of Tokyo, Center for Nuclear Study, the University of TOKYO

  • Rin Yokoyama

    Center for Nuclear Study, the University of Tokyo

  • Shoichiro Masuoka

    Center for Nuclear Study, University of Tokyo, RIKEN, Toho, Osaka, TITech, Miyazaki, LPC Caen, Tokyo, Center for Nuclear Study, the University of Tokyo