Nuclear uncertainties associated with the ejecta of a neutron-star black-hole accretion disk

M. Mumpower, T. M. Sprouse, J. Miller, K. Lund, J. Cabrera Garcia, N. Vassh, G. C. McLaughlin, R. Surman

Submitted submitted (2024)

The simulation of heavy element nucleosynthesis requires input from yet-to-be-measured nuclear properties. The uncertainty in the values of these off-stability nuclear properties propagates to uncertainties in the predictions of elemental and isotopic abundances. However, for any given astrophysical explosion, there are many different trajectories, i.e. temperature and density histories, experienced by outflowing material and thus different nuclear properties can come into play. We consider combined nucleosynthesis results from 460,000 trajectories from a neutron star-black hole accretion disk and the find spread in elemental predictions due solely to unknown nuclear properties to be a factor of a few. We analyze this relative spread in model predictions due to nuclear variations and conclude that the uncertainties can be attributed to a combination of properties in a given region of the abundance pattern. We calculate a cross-correlation between mass changes and abundance changes to show how variations among the properties of participating nuclei may be explored. Our results provide further impetus for measurements of multiple quantities on individual short-lived neutron-rich isotopes at modern experimental facilities.