Research

This is my first research project in the PhD program at the University of Alberta. Chandra X-ray observations of the globular cluster Terzan 5, spanning decades, have been utilized to study the X-ray sources within it. Extensive spectral fitting has been performed to enable the identification and classification of various types of X-ray sources, such as qLMXBs and CVs. A research paper summarizing the analysis is currently submitted to ApJ (see Publications).

This was my MS thesis project undertaken at ARIES Nainital under the guidance of Dr. Ramakant S. Yadav during August 2023 - April 2024. A spectroscopic study of 39 blue straggler stars (BSSs) in the globular cluster NGC 3201 was conducted. The spectra for these stars were sourced from the literature. Radial velocity, atmospheric parameters (Teff , logg), the abundance of magnesium (Mg), and the metallicity [Fe/H] of the blue straggler population were determined. This study provides the first estimation of [Mg/Fe] for the blue straggler stars in NGC 3201. A research paper summarizing our analysis has been accepted in RMxAA (see Publications).

This project was undertaken under the guidance of Prof. Craig Heinke at the University of Alberta as part of my Mitacs Globalink Research Internship during the summer of 2023. A Chandra observation of the globular cluster NGC 362 was analyzed to identify X-ray sources within the cluster. Spectral analysis of the brightest source revealed one quiescent low-mass X-ray binary. Using HUGS photometry, 15 potential optical/UV counterparts to these X-ray sources were identified, including AGNs, sub-subgiants, red stragglers, and active binaries. The research paper summarizing this analysis has been published in MNRAS (see Publications).

This project was undertaken under the guidance of Dr. Ramakant S. Yadav at ARIES Nainital as part of my IASc-INSA-NASI Summer Research Fellowship in 2022. Multi-wavelength data obtained from the MPG/ESO 2.2-m telescope, AstroSat’s UVIT, and Swift UVOT were utilized to perform spectral energy distribution (SED) analysis using the VO SED Analyzer tool on a cool stellar population selected from optical and UV-optical CMDs. Our analysis led to the discovery of blue lurkers for the first time in a globular cluster. The research paper summarizing this analysis has been published in MNRAS Letters (see Publications).

This project was undertaken as part of the course requirements for ASTRO565 at UAlberta, taught by Prof. Natasha Ivanova during Fall 2024. A study of the stellar populations and collision products in a simulated globular cluster with an age of 10 Gyr was presented, modeled using MESA. The isochrone of the cluster was constructed to trace various evolutionary stages, including the main sequence, subgiant branch, red giant branch, horizontal branch, and white dwarfs. Exotic objects such as blue stragglers (BSSs), blue lurkers (BLs), and yellow stragglers (YSSs) were added by considering single-single stellar collisions, with collision products evolved from the zero-age main sequence. The resulting BSSs, BLs, and YSSs were found to exhibit properties consistent with observational studies.

This group project was undertaken under the supervision of Dr. Ana Paulino-Afonso during the IAstro summer program in 2023. Local properties were analyzed using IFS data from the MUSE instrument of the VLT, and compared to global properties for 21 SN Ia host galaxies. Trends between parameters were established to test the precision of the global data.

This group project was undertaken during the Krittika Summer Projects 2022, conducted by the IIT Bombay Astronomy Club. Solar flares were studied using data from Chandrayaan-2 XSM. Previous solar flare detection models were replicated to analyze different types of stellar flares. Additionally, potential issues with the existing models were identified, and amendments were proposed to enhance their accuracy and reliability.

This duo project was undertaken as part of the course requirements for DSE302 at IISER Bhopal, taught by Dr. Tanmay Basu during Winter 2022. Various methods and techniques were employed to extract relevant parameters from the Kepler dataset provided by the NASA Exoplanet Archive. Specifically, different regression models were utilized to predict the semi-major axis of exoplanet orbits. Among these models, the Random Forest regression model demonstrated the highest performance, achieving an impressive R² score of 0.989 on the test dataset, which consisted of 1,997 exoplanets.

This group project was undertaken as part of the course requirements for DSE313 at IISER Bhopal, taught by Dr. Vaibhav Kumar during Fall 2021. A set of models based on the Convolutional Neural Network (CNN) architecture was developed, with evolutionary and chronological constraints. These models were optimized for n-index classification and adapted to the computational power of the machine being used. An accuracy of 82.7% was achieved for three-class classifications of galaxies, demonstrating the effectiveness of our approach.

This duo project was undertaken as part of the course requirements for DSE309 at IISER Bhopal, taught by Dr. Parthiban Srinivasan during Fall 2021. An ontology was developed using Owlready2 for the classification of stars based on their temperature, color, and dominant spectral lines, following the Harvard Spectral Classification Scheme. For the two-class classification of a stellar dataset, KNN, SVM, and Logistic Regression models were employed. Among these models, the highest accuracy of 88.33% was achieved. Additionally, for the seven-class classification of another stellar dataset, the KNN algorithm was used, resulting in an accuracy of 58.5%.

This group project was undertaken during the Krittika Summer Projects 2021, conducted by the IIT Bombay Astronomy Club. Knowledge and expertise were gained in various techniques, including Image Data Reduction, Aperture Photometry, PSF Photometry, and Supernova theory. Using SExtractor and PSFEx, PSF photometry was conducted on GROWTH India Telescope data. Subsequently, a light curve for the supernova event SN2018hna was generated in the r, g, and i bands. Through careful analysis, the different characteristics exhibited by the plotted light curve were examined.