학술논문
Coincidence Measurement of the Nonmesonic Weak Decay of ^{12}_{Lambda}C
Document Type
Working Paper
Author
Kim, M. J.; Ajimura, S.; Aoki, K.; Banu, A.; Bhang, H.; Fukuda, T.; Hashimoto, O.; Hwang, J. I.; Kameoka, S.; Kang, B. H.; Kim, E. H.; Kim, J. H.; Maruta, T.; Miura, Y.; Miyake, Y.; Nagae, T.; Nakamura, M.; Nakamura, S. N.; Noumi, H.; Okada, S.; Okayasu, Y.; Outa, H.; Park, H.; Saha, P. K.; Sato, Y.; Sekimoto, M.; Shin, S.; Takahashi, T.; Tamura, H.; Tanida, K.; Toyoda, A.; Tsukada, K.; Watanabe, T.; Yim, H. J.
Source
Phys.Lett. B641 (2006) 28-33
Subject
Language
Abstract
We have measured the angular correlation of the pair nucleons np and nn emitted from the nonmesonic weak decay (NMWD) of ^{12}_{Lambda}C produced via the (pi^+,K^+) reaction in coincidence measurement. The Lambda p -> np and Lambda n -> nn modes were clearly identified by measuring the back-to-back correlation of the emitted nucleon pairs which is the characteristic of two-body kinematics. From the measured nucleon pair numbers N_{nn} and N_{np}, the ratio Gamma_n/Gamma_p of the partial decay widths Gamma_n(Lambda n -> nn) and Gamma_p(Lambda p -> np) of ^{12}_{Lambda}C was extracted to be 0.51+-0.13(stat) +- 0.05(syst); this result is almost free from the ambiguity due to the nuclear final state interaction and 3-body decay process, which were inherent in the previous results. The obtained Gamma_n/Gamma_p ratio of ^{12}_{Lambda}C (p-shell) is close to that of ^5_{Lambda}He (s-shell). The results are consistent with those of recent theoretical calculations.
Comment: 13 pages, 4figures, 1 table,re-submitted to Physics Letters B
Comment: 13 pages, 4figures, 1 table,re-submitted to Physics Letters B