English

Neutron and proton energy spectra from the non-mesonic weak decays of 5_Lambda-He and 12_Lambda-C

Nuclear Experiment 2009-11-10 v1

Abstract

We have simultaneously measured the energy spectra of neutrons and protons emitted in the non-mesonic weak decays of 5_Lambda-He and 12_Lambda-C hypernuclei produced via the (pi^+,k^+) reaction with much higher statistics over those of previous experiments. The neutron-to-proton yield ratios for both hypernuclei at a high energy threshold (60 MeV) were approximately equal to two, which suggests that the ratio of the neutron- and proton-induced decay channels, Gn(Lambda n -> nn)/Gp(Lambda p -> np), is about 0.5. In the neutron energy spectra, we found that the yield of the low-energy component is unexpectedly large, even for 5_Lambda-He.

Keywords

Cite

@article{arxiv.nucl-ex/0406020,
  title  = {Neutron and proton energy spectra from the non-mesonic weak decays of 5_Lambda-He and 12_Lambda-C},
  author = {S. Okada and S. Ajimura and K. Aoki and A. Banu and H. C. Bhang and T. Fukuda and O. Hashimoto and J. I. Hwang and S. Kameoka and B. H. Kang and E. H. Kim and J. H. Kim and M. J. Kim and T. Maruta and Y. Miura and Y. Miyake and T. Nagae and M. Nakamura and S. N. Nakamura and H. Noumi and Y. Okayasu and H. Outa and H. Park and P. K. Saha and Y. Sato and M. Sekimoto and T. Takahashi and H. Tamura and K. Tanida and A. Toyoda and K. Tsukada and T. Watanabe and H. J. Yim},
  journal= {arXiv preprint arXiv:nucl-ex/0406020},
  year   = {2009}
}

Comments

13pages, 4figures, submitted to Physics Letters B