An Atomic Input to Kilonova Modelling: Opacities of LanthanidesONLINE ONLY

After detecting gravitational waves from the neutron star merger GW170817 and its electromagnetic counterpart AT2017gfo, a lot of attention has been devoted to calculations of opacities of r-process elements. Opacities affect the properties of kilonovae such as light curves and spectra. Different atomic approaches and codes including GRASP, HULLAC, FAC, and others have been used to calculate spectra and oscillator strengths of bound-bound transitions for lanthanides [1-4]. The vast amount of generated atomic data is usually visualized and compared using the expansion opacity formalism [5].

In this contribution, we present the recent results of calculations of the expansion opacities in low-ionized Ce ions, which are expected to be produced in neutron star mergers. The calculations are based on the combination of configuration interaction and the many-body perturbation theory approach [6]. This approach has been successfully used a lot in the past in high-precision evaluations of energies of low-lying levels and amplitudes of transitions between them in ions with a complex electronic structure (see, e.g., [7,8]). Within the current approach, the effect of accurate treatment of core-valence and core-core correlations on the opacities is studied in detail. Also, the obtained results are compared to the results available in the literature.

References
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