We present results from the JINA REACLIB project, an ongoing effort to maintain a current and accurate library of thermonuclear reaction rates for astrophysical applications. Ongoing updates are transparently documented and version tracked, and any set of rates is publicly available and can be downloaded via a Web interface at http://groups.nscl.msu.edu/jina/reaclib/db/. We discuss here our library V1.0, a snapshot of recommended rates for stable and explosive hydrogen and helium burning. We show that the updated reaction rates lead to modest but significant changes in full network, one-dimensional X-ray burst model calculations, compared with calculations with previously used reaction rate sets. The late time behavior of X-ray burst light curves shows significant changes, suggesting that the previously found small discrepancies between model calculations and observations may be solved with a better understanding of the nuclear input. Our X-ray burst model calculations are intended to serve as a benchmark for future model comparisons and sensitivity studies, as the complete underlying nuclear physics is fully documented and publicly available.

/pdf/the-jina-reaclib-database-its-recent-updates-and-impact-on-plgua9elb8.pdf

The jina reaclib database: its recent updates and impact on type-i x-ray bursts

http://nuclearmasses.org/resources_folder/Blaum_06.pdf

High-accuracy mass spectrometry with stored ions

The mass of the nucleus, through its binding energy, continues to be of capital importance not only for various aspects of nuclear physics, but also for other branches of physics, notably weak-interaction studies and astrophysics. The authors first describe the modern experimental techniques dedicated to the particularly challenging task of measuring the mass of exotic nuclides and make detailed comparisons. Though tremendous progress in these and the associated production techniques has been made, allowing access to nuclides very far from stability, it is still not yet possible to produce many nuclides involved in stellar nucleosynthesis, especially the $r$ process, leaving no choice but to resort to theory. The review thus goes on to describe and critically compare the various modern mass formulas that may be used to extrapolate from the data towards the neutron drip line. Special attention is devoted to the crucial interplay between theory and experiment, showing how new measurements far from stability can considerably reduce the ambiguity in extrapolations to nuclides even further away.

Recent trends in the determination of nuclear masses

The p-process of stellar nucleosynthesis: astrophysics and nuclear physics status

Recent discoveries by the Rossi X-Ray Timing Explorer indicate that most of the rapidly accreting (${u{M}{"705F}}$ -->${u{M}{"705F}}$ --> 10 -->−11 M${s}$ -->$t SUBgt {s}t/SUBgt $ --> yr -->−1) weakly magnetic (B10 -->11 G) neutron stars in the Galaxy are rotating at spin frequencies ν -->s 250 Hz. Remarkably, they all rotate in a narrow range of frequencies (no more than a factor of 2, with many within 20% of 300 Hz). I suggest that these stars rotate fast enough so that, on average, the angular momentum added by accretion is lost to gravitational radiation. The strong νs-dependence of the angular momentum loss rate from gravitational radiation then provides a natural reason for similar spin frequencies. Provided that the interior temperature has a large-scale asymmetry misaligned from the spin axis, then the temperature-sensitive electron captures in the deep crust can provide the quadrupole needed ( ~10 -->−7MR -->2) to reach this limiting situation at ν -->s ≈ 300 Hz. This quadrupole is only present during accretion and makes it difficult to form radio pulsars with ν -->s > (600-800) Hz by accreting at ${u{M}{"705F}}$ -->${u{M}{"705F}}$ --> 10 -->−10 M${s}$ -->$t SUBgt {s}t/SUBgt $ --> yr -->−1. The gravity wave strength is h -->c ~(0.5-1) × 10 -->−26 from many of these neutron stars and greater than 2 × 10 -->−26 for Sco X-1. Prior knowledge of the position, spin frequency, and orbital periods will allow for deep searches for these periodic signals with gravitational wave interferometers (LIGO, VIRGO, and the dual-recycled GEO 600 detector), and experimenters need to take such sources into account. Sco X-1 will most likely be detected first.

Gravitational radiation and rotation of accreting neutron stars

rp-process nucleosynthesis at extreme temperature and density conditions

https://people.nscl.msu.edu/~brown/brown-all-papers/219-1997-npa.627.35.pdf

Shell-model calculations for the properties of nuclei with A = 86–100 near the proton drip line

The reaction rates of neutron capture reactions on light nuclei are important for reliably simulating nucleosynthesis in a variety of stellar scenarios. Neutron capture reaction rates on neutron-rich C-, N-, and O-isotopes are calculated in the framework of a hybrid compound and direct capture model. The results are tabulated and compared with the results of previous calculations as well as with experimental results.

https://people.nscl.msu.edu/~brown/brown-all-papers/244-1999-PhysRevC.60.064614.pdf

Reaction rates for neutron capture reactions to C, N, and O isotopes to the neutron rich side of stability

Updated stellar rates for the reactions ${}^{56}\mathrm{Ni}(p,\ensuremath{\gamma}{)}^{57}\mathrm{Cu}$ and ${}^{57}\mathrm{Cu}(p,\ensuremath{\gamma}{)}^{58}\mathrm{Zn}$ are calculated by using all available experimental information as well as input data from the nuclear shell model. We calculated Coulomb and Thomas-Ehrmann shifts to obtain the unknown excitation energies and the spin/parity assignments of ${}^{58}\mathrm{Zn}.$ The astrophysical consequences are discussed.

Thermonuclear reaction rate of 56 Ni ( p , γ ) 57 Cu and 57 Cu ( p , γ ) 58 Zn

Neutron-induced nucleosynthesis plays an important role in astrophysical scenarios like in primordial nucleosynthesis in the early universe, in the s-process occurring in Red Giants, and in the α-rich freeze-out and r-process taking place in supernovae of type II. A review of the three important aspects of neutron-induced nucleosynthesis is given: astrophysical background, experimental methods and theoretical models for determining reaction cross sections and reaction rates at thermonuclear energies. Three specific examples of neutron capture at thermal and thermonuclear energies are discussed in some detail.

H. Herndl

Papers

rp-process nucleosynthesis at extreme temperature and density conditions

Shell-model calculations for the properties of nuclei with A = 86–100 near the proton drip line

Reaction rates for neutron capture reactions to C, N, and O isotopes to the neutron rich side of stability

Thermonuclear reaction rate of 56 Ni ( p , γ ) 57 Cu and 57 Cu ( p , γ ) 58 Zn

Neutron-induced nucleosynthesis