Theory Seminar

Paving the road to radiative transfer models of kilonovae in the LTE and NLTE regimesONLINE ONLY

by Dr Andreas Flörs (GSI Darmstadt)

Europe/Berlin
Description
In 2017, the electromagnetic counterpart to the gravitational wave detection of two merging neutron stars (GW170817) was observed. The light observed from the rapidly decaying material and the characteristic time scale of the fading kilonova confirmed that neutron star mergers are a viable r-process source and promising candidates for the production sites of lanthanides and, possibly, even actinides.
To identify specific elements in the ejected material of the neutron star merger spectroscopic modelling is required. This requires complex radiative transfer codes and precise knowledge of the atomic data. So far, only a single element (Sr) has been confidently detected in the ejecta of neutron-star mergers. Compared to ordinary novae and supernovae, kilonovae exhibit peculiarities which make it more difficult to model their spectra. However, understanding the production of heavy elements in kilonovae plays an important role in the chemical evolution of galaxies and, in particular, our solar system.
In the seminar I will discuss how we will use radiative transfer simulations of kilonovae to learn about the production site of r-process elements. I will review the requirements on the atomic data necessary to perform radiative transfer models and I will talk about the methods which we use in the early, high optical depth (LTE) and the late, low optical depth (NLTE) regimes. Finally, I will conclude with an outlook to the future of kilonova observations and modelling. The detection or non-detection of clear absorption or emission signatures in future kilonova observations will tell us which of our models are realised in nature.
Videoconference Rooms
GSI Theory Seminar
Zoom Meeting ID
92473872583
Host
Thomas Neff
Passcode
64278234
Zoom URL