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arXiv · hep-lat/9910009

Nucleon decay matrix elements with the Wilson quark action: an update

S. Aoki·M. Fukugita·S. Hashimoto·K-I. Ishikawa·N. Ishizuka·Y. Iwasaki·K. Kanaya·T. Kaneda·S. Kaya·Y. Kuramashi·M. Okawa·T. Onogi·S. Tominaga·N. Tsutsui·A. Ukawa·N. Yamada·T. Yoshié
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Abstract

We present preliminary results of a new lattice computation of hadronic matrix elements of baryon number violating operators which appear in the low-energy effective Lagrangian of (SUSY-)Grand Unified Theories. The contribution of irrelevant form factor which has caused an underestimate of the matrix elements in previous studies is subtracted in this calculation. Our results are 2$\sim$4 times larger than the most conservative values often employed in phenomenological analyses of nucleon decay with specific GUT models.

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S. Aoki, M. Fukugita, S. Hashimoto, K-I. Ishikawa, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneda, S. Kaya, Y. Kuramashi, M. Okawa, T. Onogi, S. Tominaga, N. Tsutsui, A. Ukawa, N. Yamada, T. Yoshié. 1999-10-04. Nucleon decay matrix elements with the Wilson quark action: an update. https://doi.org/10.1016/s0920-5632(00)91640-2

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