Research

Image: Artistic impression of eclipsing binary stars and a third body around them.

Project-1: Decoding Eclipsing Binary Systems Through The Precise Analysis Of Minima Timings.

Eclipsing binary systems are extremely useful objects for understanding fundamental astrophysical phenomena. In addition, eclipsing binary systems are valuable for studying the apsidal motions of stars and detecting exoplanets or third bodies around them.The Transiting Exoplanet Survey Satellite (TESS), a mission to look for exoplanets by means of the transit method has provided light curve data for thousands of stars, making it an ideal resource for studying eclipsing binaries. In this thesis, I used TESS data of CM Draconis (CM Dra) system to develop a novel advanced algorithm to compute high precision minima timings of eclipsing binary stars. The advantage of this technique is that it overcomes the problems of assuming that eclipses are symmetric when they are not due to the effect of spots or eccentric orbits. I have developed a template matching method to find minima timings, improving their precision with respect to other methods, such as Kwee–Van Woerden method by 1σ. Finally, I have examined the potential causes for the variation in the observed minus computed (O-C) values, which may be attributed to the existence of a third object in the CM Dra system or due to stellar spots. This thesis was conducted in collaboration with researchers from IEEC, ICE Barcelona.

Image: Illustration of NASA's TESS (Transiting Exoplanet Survey Satellite).

Project-2: Validate and characterize an exoplanetary system using TESS and TRES data.

In this project, I used photometry data from NASA's TESS (Transiting Exoplanet Survey Satellite) and radial velocity data from TRES (The Trans-Atlantic Exoplanet Survey) to validate and characterize the exoplanet TOI-2155. After the initial analysis, I found that the target is a brown dwarf. The project started with a search for a new multi- planetary system to work on. In order to achieve this, I modelled more than 50 targets (TESS objects of interest ) using the software Allesfitter. Allesfitter is a publicly available software for modeling photometric and RV data. It can accommodate multiple exoplanets, multi-star systems, and various noise models for modeling photometric and RV data. Preliminary analysis of a target using allesfitter helps us to gain an initial understanding if the target is an exoplanet or not. All the stellar and planetary parameters for our analysis are taken from NASA Exofop website. Next I verified one of the several golden outputs from allesfitter using followup radial velocity data and the target turns out to be a brown dwarf. I are currently working on advanced analysis of this target. The TESS data was taken from the MAST website of STSCI and was extracted via TOPCAT – an interactive graphical viewer and editor for tabular data. Various python packages including pandas, numpy, scipy, astropy, lightkurve, searborn, scikit-learn are being used in this project. This project is being conducted in collaboration with researchers from Washington University in St. Louis, University of Hawaii and with support from TESS Brown Dwarf Working Group (TBDWG) members.

Image: Illustration of HARPS (High Accuracy Radial Velocity Planet Searcher) in ESO, Chille.

Project-3: Estimating the age of exoplanet host stars through lithium equivalent width analysis.

In this project, I endeavor to ascertain the ages of exoplanet host stars with precision by harnessing advanced spectroscopy data analysis techniques. By collecting and processing high-quality spectroscopic data from various sources such as HARPS, the project aims to utilize the lithium equivalent width (Li EW) analysis method to determine stellar ages accurately via employing the publicly available software Eagles and PHEW. To validate the accuracy of these age estimates, comparisons with existing literature ages will be conducted while simultaneously establishing a compre- hensive database of exoplanet host star ages. This endeavor promises to significantly advance our understanding of exoplanetary systems, enhance our ability to assess habitability, and refine theories surrounding their formation and dynamics, ultimately contributing to the forefront of exoplanet research and stellar astrophysics. This project is conducted in collaboration with researchers from European Southern Observatory (ESO), Germany.

Image: Artistic view of hot jupiter WASP-101b.

Project- 4: Modeling the atmosphere of hot jupiter: WASP 101b.

In this project, I used ESO HARPS data to plot the radial velocities of WASP-101b. I use petitRadtrans (pRT) to model the atmosphere of WASP-101b. pRT is a publicly available radiative transfer code. It computes transmission and emission spectra of exoplanets and can be used for retrieval of exoplanetary atmospheres as well. I further calculate and show the abundance and transmission of different species with varying temperatures of the planet. Thus, I model the atmosphere of WASP-101b. The project gives an insight into atmospheric characterization of the exoplanet: WASP-101b. We find that Na, K, CO2, H2O are good species with strong features in WASP-101b for which it is a promising target for JWST follow-up as for similar type of spectra in WASP 39b, JWST found Na, CO, CO2, H2O. I presented this research in 2024 Assembly of the Order Of the Octopus Conference, Green Bank Observatory, West Virginia, USA.

Image: Artistic impression of terrestrial exoplanets.

Project- 5: What are the terrestrial exoplanets made of?

In this project, I used ExoPlex to determine the mass of the cores of the low-mass planets, with the ultimate goal of investigating the compositional diversity of terrestrial planets. ExoPlex is a thermodynamically self-consistent mass-radius-composition calculator where for a specific bulk molar composition of a planet, radius of a planet can be calculated if mass is known and vice versa. Additionally, it produces the planet’s core mass fraction, interior mineralogy and the pressure, adiabatic temperature, gravity and density profiles as a function of depth. In this project, I vary relative abundance ratios of various elements like Si/Mg and Fe/Mg to understand the interior composition of Super Mercuries and Super Earths. This research was conducted in collaboation with researchers from IA Portugal.

Image: Artistic impression of gravitational waves and its detectors.

Project-6: Investigating the efficiency of the SPIIR pipeline in O3 offline Gravitational Wave search.

In this project, I used the SPIIR pipeline and investigated its efficiency during the third LIGO- Virgo observing run (O3) via classifying the distribution of false alarm rates of gravitational waves via machine learning algorithm. To investigate it, I implemented K means machine learning algorithm. I presented this research on SCIOPS 2022- Artificial Intelligence for Science and Operations in Astronomy Conference, European Southern Observatory, Head Quarters, Germany, 16-20 May, 2022.

Image: Artistic impression of technosignature research.

7. Research Project - Biosignature and Techno Signature: A comparative analysis.

In this project, I analyzed the comparison between Biosignature and Techno Signature theoretically and computa- tionally via atmos packages in python. I used the data from Nasa Exoplanet Modeling and Analysis Center and Frontier Development Labs. Atmos is a library of utility code for use in atmospheric sciences. Its main functionality is currently to take input variables (like pressure, virtual temperature etc.) and information regarding assumptions (hydrostatic or low water vapor). From that, atmos calculates any desired output variable which is requested. For example, I can calculate pressure from virtual temperature and density. I can have assumptions to neglect the virtual temperature Tv and calculate temperature T. This project was done in collaboration with researcher from George Mason University, USA.

Page updated

Google Sites

Report abuse