07/09/2024
By Nicholas Sorabella

The Kennedy College of Science, Department of Physics & Applied Physics, invites you to attend a doctoral dissertation defense by Nick Sorabella entitled: The Development of Application of Smile: A Stellar Compact Object Binary System Light Curve Model. The defense will be held at Wannalancit Mills in room 305 (WAN305) on Monday, July 15 at 10 a.m. For those who wish to attend virtually, please reach out to nicholas_sorabella@student.uml.edu for the Zoom Link.

Abstract:
This work focuses on the development of a state-of-the-art gravitational lensing code we dubbed SMILE (Self-lensing Model Involving Limb-darkened Ellipsoidals) with wide application across the black hole mass spectrum; from supermassive binary black holes (SMBHs) in Active Galactic Nuclei (AGN), to binaries containing stellar-mass black holes. This code cross-cuts many subfields including: gravitational lensing (General Relativity), Doppler-boosting (Special Relativity), accretion disk physics (high energy astrophysics), and stellar limb darkening (stellar physics). These effects are modeled within an integrated post-Newtonian orbital mechanics code, making this a generalized tool (directly applicable to systems across the mass spectrum) that will be widely relevant as the next generation of observatories become sensitive to this new channel for discovery. We detail the mathematical theories behind each component of SMILE as well as the total summation of all effects into our synthetic light curves. From there, we apply SMILE to real data from a wide array of example binary systems including stellar mass self-lensing systems, ellipsoidal variables, and Spikey, the first known self-lensing supermassive black hole binary system. We discuss the search for new self-lensing systems with the aid of the Transiting Exoplanet Search Satellite (TESS), the sources of potential false-positive self-lensing signals, and the detection of the first self-lensing pulses by TESS.