Speaker
Description
Currently, the only accretion flows than can be imaged directly -- supermassive black holes (BHs) at the centres of galaxies via EHT -- evolve on timescales much greater than a human lifetime. In contrast, X-ray binaries (XRBs) in our Galaxy provide ideal observational laboratories. Their frequently recurring bright outbursts present a unique opportunity to study an evolving astrophysical accretion disc in real time. As XRBs are far too small and distant to be imaged directly (being $\sim$50 times smaller in angular size on the sky than their supermassive counterparts), we have built a new tomographic imaging technique that allows one to empirically map the geometry, structure, and -- for the first time -- thermodynamic properties, of XRB accretion discs on micro-arcsecond scales. By pairing modern doppler tomography with powerful machine learning algorithms, we create a unique transformation between spatially varying accretion disc gas properties and time-variable spectral emission line profiles. In this talk, I will demonstrate how, with just an ``observed'' trailed optical spectrum, physical parameter tomography is able to reconstruct velocity-resolved maps depicting both the distribution of temperature and density, as well as the geometry of, the gas in an outbursting XRB accretion disc.
| Contribution | Oral talk |
|---|---|
| Affiliation | McGill University |
| bailey.tetarenko@mcgill.ca |
