Photo-nuclear reaction rates of ${}^{157,159}$Ho and ${}^{163,165}$Tm and their impact in the $\gamma$--process

Abstract

Reliable photo-nuclear reaction rates at the stellar conditions are essential to understand the origin of the heavy stable neutron-deficient isotopes between ${}^{74}$Se and ${}^{196}$Hg-p-nuclei, however, many reaction rates of relevance still have to rely on the Hauser-Feshbach model due to rare experimental progress. One such case is in the mass range of 160 for Dy, Er, Ho and Tm isotopes. In this work we attempt to constrain the Hauser-Feshbach model in the TALYS package by reproducing the available experimental data of ${}^{160}$Dy($p,\gamma$)${}^{161}$Ho and ${}^{162}$Er($p,\gamma$)${}^{163}$Tm in the $A\sim 160$ mass region, and examine the effects of level density, gamma strength function and the optical model potential. The constrained model then allows us to calculate the reaction rates of ${}^{157,159}$Ho($\gamma$, $p$) and ${}^{163,165}$Tm($\gamma$, $p$) for the $\gamma$-process nucleosynthesis in carbon-deflagration SNe Ia model. Our recommended rates differ from the JINA REACLIB by more than 1 order of magnitude in the temperature range of 2-3 GK. This results in the changes of final abundance of $p$-nuclei in the $A\sim 160$ mass range by -5.5-3\% from those with JINA, which means that the ($\gamma$, $p$) reactions uncertainty is not predominant for the synthesis of these nuclei.

12 pages,7 figures

References in corpus (17)

• Galactic Chemical Evolution and solar s-process abundances: dependence on the 13C-pocket structure
• Sensitivity of p-Process Nucleosynthesis to Nuclear Reaction Rates in a 25 Solar Mass Supernova Model
• The 12C + 12C reaction and the impact on nucleosynthesis in massive stars
• Alpha-induced cross sections of 106Cd for the astrophysical p-process
• Radiogenic p-isotopes from SNIa, nuclear physics uncertainties and Galactic chemical evolution compared with values in primitive meteorites
• New estimate for the time-dependent thermal nucleosynthesis of ${}^{180}$Ta${}^m$
• The $\gamma$-process nucleosynthesis in core-collapse supernovae. I. A novel analysis of $\gamma$-process yields in massive stars
• Cross sections for proton-induced reactions on Pd isotopes at energies relevant for the gamma process
• Impact of hypernova νp-process nucleosynthesis on the galactic chemical evolution of Mo and Ru
• Heavy Elements Nucleosynthesis On Accreting White Dwarfs: building seeds for the p-process
• Cross-section measurement of the ${}^{130}$Ba(p,$\gamma$)${}^{131}$La reaction for $\gamma$-process nucleosynthesis
• First Direct Measurement of an Astrophysical p-Process Reaction Cross Section Using a Radioactive Ion Beam
• Production of $p$-nuclei from $r$-process seeds: the $\nu r$-process
• Measurements of ${}^{160}$Dy($p,\gamma$) at energies relevant for astrophysical $\gamma$ process
• Cross Sections of the ${}^{83}$Rb(p,$\gamma {)}^{84}$Sr and ${}^{84}$Kr(p,$\gamma {)}^{85}$Rb Reactions at Energies Characteristic of the Astrophysical $\gamma$ Process
• Cross Section Measurement of the ${}^{82}$Kr(p,$\gamma$)${}^{83}$Rb Reaction in Inverse Kinematics
• Thermonuclear 17O(n,gamma)18O reaction rate and its astrophysical implications