Dev R Sadaula

Background

About Dev R Sadaula

I am a postdoctoral research associate at NASA Goddard Space Flight Center (GSFC), where I study Active Galactic Nuclei (AGN) with a focus on changing-look AGN, AGN outflows, and time-domain astrophysics. My research involves analyzing X-ray observations from telescopes such as XMM-Newton and NICER to investigate the variability of AGN, the properties of ionized outflows, and their connection to the accretion disk and corona. I am currently involved in the multi-wavelength studies of the newly born jet in 1ES 1927+654, collaborating with researchers at GSFC and UMBC to understand its evolution and impact on the surrounding environment. During my PhD and postdoctoral research, I developed a computational tool for modeling warm absorbers (WAs) in AGN using time-dependent photoionization physics. Unlike traditional models that assume photoionization equilibrium, my approach accounts for non-equilibrium ionization effects, providing a more accurate representation of how WAs respond to rapid changes in the AGN’s radiation field. This work enables density diagnostics of WAs by measuring the time lag between AGN flux variations and absorber response, helping to determine their physical properties and location within the AGN. With expertise in X-ray spectroscopy, time-resolved spectral analysis, and data modeling, I continue to explore new ways to advance our understanding of AGN variability, outflows, and their role in galaxy evolution.