Multicolor photometry and parameters estimation of three transiting Jupiter-sized exoplanets; TrES-3b, WASP-2b and HAT-P-30b

Abstract

Precise and frequent photometric follow-up studies of transit light curves are indispensable when accurately characterizing extrasolar planets. We present new multi-wavelength photometry of three transiting “Hot Jupiters” — TrES-3b, WASP-2b and HAT-P-30b (WASP-51b). Data were acquired from an 0.8 meter telescope at Tarleton State University. When combined with data from the literature, this allowed us to redetermine system parameters. GCX reduction pipeline and TAP - modeling and light curve fitting package was used to analyze the extracted light curves. Weighted mean values were used to estimate the parameters from BVRI filters for three exoplanetary systems and compared them with previous published results. From our study, TreS-3b with a mass of Mp = 1.7730±0.02Mjup and Rp = 1.3047±0.04Rjup, appears to be 0.2±0.03Mjup less massive than previously published by O’donovan et al. (2007) and Sozzetti et al. (2009), while HAT-P-30b, which has a mass of Mp = 0.7006±0.041Mjup and Rp = 1.5109±0.0557Rjup appears to be a bloated “Hot Jupiter”. Additionally, we compared the results of our broadband photometric analysis with previous studies to search for transit depth wavelength dependence. We found a flat spectrum across optical wavelengths (except WASP-2b in R-band) for TrES-3b and WASP-2b, indicating the presence of clouds in their atmospheres. HAT-P-30b had a significantly larger radius in B filter with Rp = 1.613±0.05Rjup, resulting from Rp/R∗ = 0.1334±0.004, which was secondarily confirmed by the atmospheric scale height value, H = 1450±38km, indicating that HAT-P-30b is an inflated “Hot Jupiter”.