Abstract Details

Name: Suman Saha
Affiliation: Indian Institute of Astrophysics
Conference ID: ASI2020_199
Title : Transit photometry of extra-solar planets
Authors and Co-Authors : Suman Saha
Abstract Type : Oral
Abstract Category : Stars, ISM and Galaxy
Abstract : Transit photometry is a powerful tool to study the physical properties of Extra-Solar planets (or Exoplanets). We target exoplanets, which are newly discovered and have large uncertainties in their estimated physical parameters from previous studies, for precise transit-photometric follow-up using 2m Himalayan Chandra Telescope (HCT), Indian Astronomical Observatory, Hanle and 1.3m J.C. Bhattacharya Telescope (JCBT), Vainu Bappu Observatory, Kavalur. Taking advantage of the large apertures of these telescopes, we have obtained high S/N (>200) photometric observations for the predicted transit events. In order to eliminate the variability in the photometric data due to air-mass effect and atmospheric transparency, we have performed differential photometry to obtain the transit light-curves. In order to reduce the fluctuations in the light-curves due to various sources, like stellar activity, atmospheric turbulence etc., we have processed them with wavelet denoising and Gaussian process correlated noise modelling techniques. We have fitted the transit light-curves to the analytical transit function given by Mandel & Agol (2002) using Markov-chain Monte-Carlo (MCMC) technique to estimate the precise values for several physical parameters, such as the mid-transit time, the impact parameter of transit, the ratio of stellar radius to the distance of the planet, the ratio of planet to stellar radius and the quadratic limb darkening coefficients of the star. In this talk, I shall present a few results and compare our results with the existing observational data. I shall also discuss about the survey observations, that aims for the discovery of new exoplanets.