Homogeneous transit timing analyses of 10 exoplanet systems

Abstract

We study the transit timings of 10 exoplanets in order to investigate potential Transit Timing Variations (TTVs) in them. We model their available ground-based light curves, some presented here and others taken from the literature, and homogeneously measure the mid-transit times. We statistically compare our results with published values and find that the measurement errors agree. However, in terms of recovering the possible frequencies, homogeneous sets can be found to be more useful, of which no statistically relevant example has been found for the planets in our study. We corrected the ephemeris information of all ten planets we studied and provide these most precise light elements as references for future transit observations with space-borne and ground-based instruments. We found no evidence for secular or periodic changes in the orbital periods of the planets in our sample, including the ultra-short period WASP-103 b, whose orbit is expected to decay on an observable timescale. Therefore, we derive the lower limits for the reduced tidal quality factors (Q$^{\prime }_{\star }$) for the host stars based on best fitting quadratic functions to their timing data. We also present a global model of all available data for WASP-74 b, which has a Gaia parallax-based distance value ∼25 per cent larger than the published value.

A precise blue-optical transmission spectrum from the ground: Evidence for haze in the atmosphere of WASP-74b

“…The exoplanet has a high equilibrium temperature of 1900 K, a moderate surface gravity of 10 m s −2 and completes a full orbit in 2.1 days. A search for transit timing variations from archival, published and new data by Baştürk et al (2022) revealed no trends of any kind to the time of mid-transit consistent with a stable orbit.…”

“…Motivated by the potential of this technique, we performed a search for the blue-optical increase of the planet radius during the transit of exoplanet WASP-74b. The WASP-74 system (Hellier et al 2015;Mancini et al 2019;Garhart et al 2020;Luque et al 2020;Baştürk et al 2022) consists of an F9 dwarf star with a mass of ∼1.3 M and a radius of ∼1.5 R and an inflated hot Jupiter with a mass of ∼0.9 M Jup and a radius of ∼1.4 R Jup . The host star has an effective temperature of ∼6000 K and a metallicity of ∼0.4 (Sousa et al 2021).…”

Discovery of a Short Period Pulsator from Istanbul University Observatory

“…Exoplanet host star XO-2 has been observed within a research program 1 that investigates the transit timing variations with a similar fashion given in Baştürk et al (2022). During these observations, variability of one of the comparison star in the field was noticed.…”

Discovery of a Short Period Pulsator from Istanbul University Observatory

“…Exoplanet host star XO-2 has been observed within a research program that investigates the transit timing variations with a similar fashion given in Baştürk et al (2022). During these observations, variability of one of the comparison star in the field was noticed.…”