The Gravitational Wave Toolbox: modelling electromagnetic counterparts of gravitational wave sources

Keywords
Loading...
Thumbnail Image
Issue Date
2021-07-15
Language
en
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
In recent years, the field of gravitational wave (GW) physics has become a central part of astrophysics. As a result of this, an increasing number of physicists, both within and outside the GW community will be using GW observations in their research projects. Therefore, especially now, it is of the utmost importance that information about GW sources and their detectability remains easily accessible. The Gravitational Wave Toolbox (https://gw-universe.org) is a tool that aims to take care of this task. It is a user-friendly program, with which one can make quick and efficient computations related to the detectability of GW sources and the properties of GW detectors. As of yet,the Toolbox does not include the possibility so simulate electromagnetic (EM) counterparts (e.g. short gamma-ray bursts, kilonovae) of GW events. As we are currently at the start of a multi-messenger astronomy era, joint GW-EM observations have become a very important aspect of GW physics. As such, inclusion of EM signatures of GW sources in the Toolbox would significantly increase the usability and the applicability of this program. The aim of this study is to add models of EM counterparts to GW sources to the GW Toolbox.We set up models for short gamma-ray bursts (sGRBs) and kilonovae (KNe), as well as EM output of stellar-mass and supermassive black hole binaries. For our sGRB model, we employ an analytical top-hat jet framework, with which we can simulate the sGRB flux and spectrum. We compare this model with observations of GRB170817A,and find that we can recover this well with typical GRB parameters. To predict KN lightcurves, we make use of the existing program gwemlightcurves. In this model,we can use the masses and spins of a binary neutron star (BNS) or black hole - neutron star (BH-NS) to compute the mass and velocity of matter ejecta from the binary.From here, through interpolation with photometric datasets from radiative transfer simulations, we can compute the KN lightcurve in different passbands. We compare this model with observations of AT2017gfo, and conclude that its performance is good enough, even though it slightly underestimates the KN brightness. Additionally, we include and show the results of several order-of-magnitude luminosity estimates for the EM output of stellar-mass and supermassive black hole binaries. Subsequently, we illustrate the synergies and trade-offs between GW detectors and M instruments by using the Toolbox to simulate a universe filled with GW sources, and computing the peak GRB flux for each of them. Lastly, we include a clear visualisation of how these models will be implemented into the framework of the GW Toolbox.
Description
Citation
Faculty
Faculteit der Wiskunde, Natuurkunde en Informatica