My research is focused on exploring the strong-field region around black holes, and other compact objects, by studying the detailed structure of the accretion disks and their observable signatures in the X-ray spectrum. Mass and spin---the two fundamental properties of black holes---deform and twist space-time in the inner regions, shaping the way material is accreted and dramatically affecting the emitted X-ray spectrum. Using radiative transfer, general relativity, and the most updated atomic data, I have developed and maintain sophisticated theoretical models for the interpretation of observational data from a large selection of past and present X-ray observatories. My ultimate goal is to deepen our understanding of the physical properties and temporal evolution of accreting black holes and neutron stars, in order to set observational constraints for fundamental physics in the strong gravity limit.
Global spectroscopic studies of several bright black holes using our reflection models and new calibration tools for RXTE. These synoptic studies provide a panoramic view of black hole behavior and advance the measurements of black hole spin.
Calculation of atomic data required for the modeling of K-shell emission in the X-ray spectra of astrophysical sources in the high-density limit (approx. 1.e18-1.e22/cm^3). These will be incorporated into the XSTAR database, and have direct relevance for modeling X-ray reflection from accretion disks around black holes.
Comprehensive study of accreting black holes by using relativistic spectral-timing reflection models (relxill, reltrans) to X-ray data of a representative sample of stellar-mass and supermassive black hole systems. This will provide a detailed description of the accretion physics in the strong gravity regime.
Recorded public talks, school lectures, and conference presentations (some in Spanish)
I am enthusiastic about mentoring and transferring expertise and knowledge. I have supervised several students and postdocs in the US and abroad, and always looking to expand my collaborations.
* PhD Thesis Co-advisor, Kishalay Choundry, Fudan University, Shanghai, China
* PhD Thesis Advisor, Efrain Gatuzz, Venezuelan Institute of Scientific Research (IVIC), Caracas, Venezuela
* Undergrad Thesis Advisor, Raul Velasquez, La Universidad del Zulia, Maracaibo, Venezuela
* 2021: Maryanne Xu, Eunice Beato, Jennifer Rodriguez, Hanbai Lyu, and Zhibo Yu
* 2020: Jessie Miller
* 2019: Feiyang Liu and Yerong Xu
* 2018: Honghui Liu