Refined Ephemeris for Four Hot Jupiters using Ground-Based and TESS Observations

WASP-12 b, WASP-33 WASP-36 and WASP-46 b are four transiting planetary systems which we have studied. These systems' light curves were derived from observations made by the Transiting Light Exoplanet Survey Satellite (TESS) some ground-based telescopes. We used Exofast-v1 to model these calculate mid-transit times. Also, plotted TTV diagrams for them using times those available within literature. O-C analysis of timings enables us refine linear ephemeris systems. measured WASP-12's tidal quality factor based on adding TESS data as Q*'=(2.13+-0.29)*10^5. According analysis, orbital period system is increasing. The not shown any obvious quadratic trend in their diagrams. increase most likely due inaccurate liner that has increased over time. So, more needed evaluate whether or there an decay