Neutron star merger accretion discs can launch neutronrich winds of >10−2M⊙. This ejecta is a prime site for rprocess nucleosynthesis, which will produce a range of radioactive heavy nuclei. The decay of these nuclei releases enough energy to accelerate portions of the wind by ∼0.1c. Here, we investigate the effect of rprocess heating on the dynamical evolution of disc winds. We extract the wind from a 3D general relativistic magnetohydrodynamic simulation of a disc from a postmerger system. This is used to create inner boundary conditions for 2D hydrodynamic simulations that continue the original 3D simulation. We perform two such simulations: one that includes the rprocess heating, and another one that does not. We follow the hydrodynamic simulations until the winds reach homology (60 s). Using timedependent multifrequency multidimensional Monte Carlo radiation transport simulations, we then calculate the kilonova light curves from the winds with and without dynamical rprocess heating. We find that the rprocess heating can substantially alter the velocity distribution of the wind, shifting the massweighted median velocity from 0.06c to 0.12c. The inclusion of the dynamical rprocess heating makes the light curve brighter and bluer at $\sim 1\, \mathrm{d}$ postmerger. However, the highvelocity tail of the more »
 Publication Date:
 NSFPAR ID:
 10361432
 Journal Name:
 Monthly Notices of the Royal Astronomical Society
 Volume:
 510
 Issue:
 2
 Page Range or eLocationID:
 p. 29682979
 ISSN:
 00358711
 Publisher:
 Oxford University Press
 Sponsoring Org:
 National Science Foundation
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