# Precise photometric transit follow-up observations of five close-in exoplanets : update on their physical properties

## TL;DR

This study presents high-precision photometric follow-up observations of five hot Jupiter exoplanets, utilizing advanced noise reduction and modeling techniques to refine their physical parameters with greater accuracy.

## Contribution

It demonstrates the effectiveness of wavelet denoising and Gaussian process modeling in improving the precision of exoplanet transit parameter estimation.

## Key findings

- Enhanced transit light curves with high S/N ratios.
- More precise planetary physical parameters.
- Validation of wavelet denoising in transit analysis.

## Abstract

We report the results of the high precision photometric follow-up observations of five transiting hot jupiters - WASP-33b, WASP-50b, WASP-12b, HATS-18b and HAT-P-36b. The observations are made from the 2m Himalayan Chandra Telescope at Indian Astronomical Observatory, Hanle and the 1.3m J. C. Bhattacharyya Telescope at Vainu Bappu Observatory, Kavalur. This exercise is a part of the capability testing of the two telescopes and their back-end instruments. Leveraging the large aperture of both the telescopes used, the images taken during several nights were used to produce the transit light curves with high photometric S/N ($>200$) by performing differential photometry. In order to reduce the fluctuations in the transit light curves due to various sources such as stellar activity, varying sky transparency etc. we preprocessed them using wavelet denoising and applied Gaussian process correlated noise modeling technique while modeling the transit light curves. To demonstrate the efficiency of the wavelet denoising process we have also included the results without the denoising process. A state-of-the-art algorithm used for modeling the transit light curves provided the physical parameters of the planets with more precise values than reported earlier.