We will review atomic processes relevant to kilonovae and the current
state-of-play in servicing the needs of modellers.
The atomic processes relevant to kilonovae separate into their two plasma phases: the first few days, where LTE holds, and the subsequent non-LTE phase. In LTE, where fractional ionic abundances and level populations are given by the Saha--Boltzmann equations, the main...
In kilonovae, freshly-synthesized r-process elements imprint absorption features on optical spectra, as observed in AT2017gfo. These spectral features provide insights into the physical conditions of the r-process, but measuring the detailed composition of the ejecta is challenging. [Vieira et al. (2023)][1] introduced Spectroscopic r-Process Abundance Retrieval for Kilonovae (SPARK), a tool...
The atomic properties of r-process elements are predicted to play an important role in determining the electromagnetic emission from kilonovae, which result from the merger of two neutron stars. More specifically, the radiative opacity is an important quantity that determines the flow of radiation through the ejecta and wind material that result from the merger. In this talk, we discuss the...
Kilonovae light-curves depend on the efficiency with which beta decay e$^\pm$ deposit their energy in the expanding ejecta. We show that the time $t_{\rm e}$, at which the deposited energy fraction drops to $1/e$, depends mainly on ejecta density and velocity, and only weakly on the initial electron fraction $Y_e$ and entropy $s_0$: $t_{\rm e} = t_0 \times (\rho t^3/(\rho t^3)_0)^{s_{\rm e}}$...
