RTBinary

My RTBinary project aims at finding unique signatures of massive black hole binaries embedded in gaseous environments through 3D radiative transfer hydrodynamics simulations. The main goal is to provide reliable theoretical predictions that allow to confirm (or discard) existing candidates.

The ability to detect a population of Massive Black Hole Binaries (MBHBs) is key for the understanding of galaxy mergers and for the characterization of the gravitational waves signal that we expect to detect with the upcoming laser interferometer space antenna (LISA) and the existing pulsar timing array (PTA) experiments.

The MBHBs candidates proposed to date have been identified through the electromagnetic emission of their surrounding gas via spectroscopic or photometric observations.  Finding new candidates is now within our reach thanks to the Zwicky Transient Facility, the LSST Vera Rubin Observatory and the launch of Einstein Probe.

The true nature of these MBHB candidates can be tested through the comparison with a complete underlying theoretical model. 

In this context the RTBinary project aims at producing a library of synthetic electromagnetic spectra and light curves via radiative transfer hydrodynamical (RTHD) simulations of circumbinary gaseous discs around MBHBs.

 We can follow the MBHB inspiral within the gaseous circumbinary disc with 2.5PN correction to the binary dynamics, implemented in the hydrodynamics code GIZMO (Franchini et al. 2024a). The left and right circumbinary discs have aspect ratio H/R = 0.1 and H/R = 0.03 respectively.

We can extract synthetic light curves by calculating the optically thick emission from the disc during inspiral, merger and post merger (for details see Franchini et al. 2024a).