UofM Astrophysicist Investigates the Environments around Supermassive Black Holes

Examining Black Holes with the James Webb Space Telescope

Dr. Francisco Müller-Sánchez was recently awarded two grants by NASA for use of the James Webb Space Telescope (JWST) to study the cores of galaxies with active supermassive black holes. 

In one study, Müller-Sánchez and a team of colleagues from the University of Colorado Boulder, the California Institute of Technology, Yale University, Harvard University, the University of California, Los Angeles, the National Radio Astronomy Observatory, the University of Florida and the University of Chile will focus on how gravitational waves have impacted the evolution of a galaxy with two supermassive black holes.  A gravitational wave (GW) is an invisible ripple in space. GWs travel at the speed of light and as they move through space they squeeze and stretch anything in their path (learn more about them here).

The team will obtain data from JWST observations of the most compelling GW recoiling supermassive black hole (SMBH) candidate in the universe. According to Müller-Sánchez, "Astrophysics has now entered the era of gravitational wave and observations of GWs associated with SMBH mergers, via pulsar timing arrays or space-based interferometers, are on the horizon. Until these experiments are fully optimized for the detection of low-frequency GWs from coalescing SMBHs, the most promising evidence for SMBH mergers may come from signatures of GW recoil. When two galaxies merge, their two SMBHs form a SMBH binary and the SMBH binary is expected to eventually merge and produce strong GWs. If the merging SMBHs have unequal masses or spins, then the GW emission is asymmetric and imparts a velocity kick to the merged SMBH, which can cause SMBHs to wander for more than a billion years."

The detection of a GW recoiling SMBH would have an enormous impact on modern-day physics. This would be momentous as a confirmation of the general relativistic prediction that recoils are an expected consequence of SMBH mergers. A recoiling SMBH discovery would also provide the first observational evidence that some SMBHs do in fact merge in timescales less than the age of the universe.

In a second project also using JWST data, Müller-Sánchez will conduct a spatially and kinematically resolved study of the circumnuclear region of NGC 4151 to investigate, with unprecedented detail, Active Galatic Nuclei feeding and feedback. As the prototypical Seyfert 1 galaxy and one of the nearest AGN, NGC 4151 provides an outstanding opportunity to obtain meaningful constraints for models incorporating these processes to regulate black hole-galaxy co-evolution. The characterization of the nuclear environment in NGC 4151 will be done by tracing outflows via ionized and coronal gas emission to establish the energetics of the outflowing gas and potential for feedback into the host galaxy, tracing inflows via molecular hydrogen gas emission from which the driving inflow mechanism can be identified and an inflow rate obtained via modeling, using the wide range of available molecular lines in the near-IR to establish their connection with the obscuring torus, and obtaining a molecular gas-based black hole mass estimate.

The analyses of the JWST data cubes of NGC 4151 will provide the most detailed characterization of the environment around an active supermassive black hole to date. Specifically, we will be able to show how a prototypical type 1 AGN is fed and how it influences its host galaxy.

For more information on the importance of this research, check out this article. For more information on this research, contact Müller-Sánchez at fmllrsnc@memphis.edu.