Research
Tidal locking in Eclipsing Binaries and Tidal spin-up in Hot Jupiter Hosts
My current work under the supervision of Dr. David Martin at the Ohio State University, aims to compare tidal locking in eclipsing binaries (EBs) with tidal spin-up in Hot Jupiter (HJ) hosts using TESS photometry. A comparison across such a range of mass ratios covering 163 EBs and 192 HJs would be something new and exciting. I am analyzing the TESS light curves of these targets to study spot modulations for estimating stellar rotation rates, understanding spot evolution and morphology, and studying tides and effects like ellipsoidal variations. The figure on the left illustrates a TESS light curve of an EBLM target after removing the eclipses, a Lomb-Scargle periodogram for estimating the rotation rate, and a light curve folded at the estimated rotation rate indicating a strong rotation rate signal.
M-Dwarf : Characterization and Spots
M-dwarfs are popular targets for searching potentially habitable planets. Usually, our constraints on planets are determined by the constraints on the host stars. However, for M-dwarfs, precisely estimating mass, radii, temperatures, and metallicity can be challenging as they are faint. To solve this, I worked on two papers to provide well-characterized M-dwarfs. I also worked to constrain the rotation rate and differential rotation in a tight M-dwarf binary, CM Draconis, and connect it to the flare location. Being highly active, M-dwarfs give off a lot of radiation, which is detrimental to life. This study would help us understand whether flares on M-dwarfs are equatorial like our Sun or polar, which could indicate the possibility of habitable worlds around M-dwarfs. (For more details, check out our latest paper)
Open Clusters : Fundamental properties and Dynamics
I led a project on Open clusters, collaborating with Dr. Devendra Bisht at the Indian Centre for Space Physics Kolkata. Such clusters are practical tools for studying stellar formation and evolution. We investigated a poorly-studied open cluster, NGC 5288, using the Gaia DR3 data for the first time ever. I precisely estimated the cluster's basic astrophysical parameters, such as cluster center, radius, age, distance and metallicity. We also found the mass function slope to comment on the dynamical state of the cluster and concluded that it is dynamically relaxed. Finally, we traced the cluster's orbital path in the Milky Way Galaxy using Galactic Potential Model and found that NGC 5288 follows a circular path around the Galactic center.. The figure on the left illustrates the Identification map of NGC 5288 taken from DSS. (For more details, check out this paper)
Correlation Between the Optical and Radio Flux Variations in a BL Lac object, OJ287
OJ287 is a bright blazer and one of the best candidates to study black holes as it hosts a supermassive black hole binary at its center. It is a prime candidate for establishing the connections between radio and optical emissions in active galactic nuclei (AGNs). I worked on a project under the supervision of Prof. A. Gopakumar at the Tata Institute of Fundamental Research, Mumbai to study the correlation between the optical and radio flux variations in OJ287. Furthermore, we found that the optical radiations preceded the radio ones and established a relation linking the time delay in observing the maximum correlation with the corresponding radio frequency of light. We used radio fluxes measured at three different frequencies (4.8, 8.0, and 14.5 GHz), and optical V-band flux extended over 100 years of data. A graph showing the time delay of maximum correlation for different radio frequencies is shown on the left.