57Zn β-delayed proton emission establishes the 56Ni rp-process waiting point bypass
oleh: M. Saxena, W. -J Ong, Z. Meisel, D.E.M. Hoff, N. Smirnova, P.C. Bender, S.P. Burcher, M.P. Carpenter, J.J. Carroll, A. Chester, C.J. Chiara, R. Conaway, P.A. Copp, B.P. Crider, J. Derkin, A. Estradé, G. Hamad, J.T. Harke, R. Jain, H. Jayatissa, S.N. Liddick, B. Longfellow, M. Mogannam, F. Montes, N. Nepal, T.H. Ogunbeku, A.L. Richard, H. Schatz, D. Soltesz, S.K. Subedi, I. Sultana, A.S. Tamashiro, V. Tripathi, Y. Xiao, R. Zink
| Format: | Article |
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| Diterbitkan: | Elsevier 2022-06-01 |
Deskripsi
We measured the Zn57 β-delayed proton (βp) and γ emission at the National Superconducting Cyclotron Laboratory. We find a Zn57 half-life of 43.6±0.2 ms, βp branching ratio of (84.7±1.4)%, and identify four transitions corresponding to the exotic β-γ-p decay mode, the second such identification in the fp-shell. The p/γ ratio was used to correct for isospin mixing while determining the Zn57 mass via the isobaric multiplet mass equation. Previously, it was uncertain as to whether the rp-process flow could bypass the textbook waiting point Ni56 for astrophysical conditions relevant to Type-I X-ray bursts. Our results definitively establish the existence of the Ni56 bypass, with 14-17% of the rp-process flow taking this route.