Nucleon-nucleon coincidence measurement in the non-mesonic weak decay of 5_Lambda-He and 12_Lambda-C hypernuclei

S. Okada; S. Ajimura; K. Aoki; A. Banu; H. C. Bhang; T. Fukuda; O. Hashimoto; J. I. Hwang; S. Kameoka; B. H. Kang; E. H. Kim; J. H. Kim; M. J. Kim; T. Maruta; Y. Miura; Y. Miyake; T. Nagae; M. Nakamura; S. N. Nakamura; H. Noumi; Y. Okayasu; H. Outa; H. Park; P. K. Saha; Y. Sato; M. Sekimoto; T. Takahashi; H. Tamura; K. Tanida; A. Toyoda; K. Tsukada; T. Watanabe; H. J. Yim

doi:10.1016/j.nuclphysa.2005.02.035

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arXiv · nucl-ex/0411018

Nucleon-nucleon coincidence measurement in the non-mesonic weak decay of 5_Lambda-He and 12_Lambda-C hypernuclei

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Abstract

We have measured both yields of neutron-proton and neutron-neutron pairs emitted from the non-mesonic weak decay process of 5_Lambda-He and 12_Lambda-C hypernuclei produced via the (pi^+,K^+) reaction for the first time. We observed clean back-to-back correlation of the np- and nn-pairs in the coincidence spectra for both hypernuclei. The ratio of those back-to-back pair yields, Nnn / Nnp, must be close to the ratio of neutron- and proton-induced decay widths of the decay, Gn(Lambda n -> nn)/Gp(Lambda p -> np). The obtained ratios for each hypernuclei support recent calculations based on short-range interactions.

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S. Okada, S. Ajimura, K. Aoki, A. Banu, H. C. Bhang, T. Fukuda, O. Hashimoto, J. I. Hwang, S. Kameoka, B. H. Kang, E. H. Kim, J. H. Kim, M. J. Kim, T. Maruta, Y. Miura, Y. Miyake, T. Nagae, M. Nakamura, S. N. Nakamura, H. Noumi, Y. Okayasu, H. Outa, H. Park, P. K. Saha, Y. Sato, M. Sekimoto, T. Takahashi, H. Tamura, K. Tanida, A. Toyoda, K. Tsukada, T. Watanabe, H. J. Yim. 2004-11-09. Nucleon-nucleon coincidence measurement in the non-mesonic weak decay of 5_Lambda-He and 12_Lambda-C hypernuclei. https://doi.org/10.1016/j.nuclphysa.2005.02.035

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