High-Precision Mass Measurement of ^{56}Cu and the Redirection of the rp-Process Flow
| Autor: | A A, Valverde, M, Brodeur, G, Bollen, M, Eibach, K, Gulyuz, A, Hamaker, C, Izzo, W-J, Ong, D, Puentes, M, Redshaw, R, Ringle, R, Sandler, S, Schwarz, C S, Sumithrarachchi, J, Surbrook, A C C, Villari, I T, Yandow |
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| Rok vydání: | 2017 |
| Zdroj: | Physical review letters. 120(3) |
| ISSN: | 1079-7114 1674-1137 |
| Popis: | We report the mass measurement of ^{56}Cu, using the LEBIT 9.4 T Penning trap mass spectrometer at the National Superconducting Cyclotron Laboratory at Michigan State University. The mass of ^{56}Cu is critical for constraining the reaction rates of the ^{55}Ni(p,γ) ^{56}Cu(p,γ) ^{57}Zn(β^{+}) ^{57}Cu bypass around the ^{56}Ni waiting point. Previous recommended mass excess values have disagreed by several hundred keV. Our new value, ME=-38626.7(7.1) keV, is a factor of 30 more precise than the extrapolated value suggested in the 2012 atomic mass evaluation [Chin. Phys. C 36, 1603 (2012)CPCHCQ1674-113710.1088/1674-1137/36/12/003], and more than a factor of 12 more precise than values calculated using local mass extrapolations, while agreeing with the newest 2016 atomic mass evaluation value [Chin. Phys. C 41, 030003 (2017)CPCHCQ1674-113710.1088/1674-1137/41/3/030003]. The new experimental average, using our new mass and the value from AME2016, is used to calculate the astrophysical ^{55}Ni(p,γ) and ^{56}Cu(p,γ) forward and reverse rates and perform reaction network calculations of the rp process. These show that the rp-process flow redirects around the ^{56}Ni waiting point through the ^{55}Ni(p,γ) route, allowing it to proceed to higher masses more quickly and resulting in a reduction in ashes around this waiting point and an enhancement to higher-mass ashes. |
| Databáze: | OpenAIRE |
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