Transit Timing Analysis in the HAT-P-32 system

TL;DR

This study analyzes 45 transits of exoplanet HAT-P-32b to refine system parameters and investigate potential additional planets through transit timing variations, ultimately constraining TTV amplitudes to under 1.5 minutes.

Contribution

The paper provides new high-precision transit observations and refines system parameters, while also constraining the presence of additional planets via transit timing analysis.

Findings

Refined system parameters such as inclination and radius ratio.

No significant TTVs detected above 1.5 minutes.

Linear ephemeris refined by 21 milliseconds.

Abstract

We present the results of 45 transit observations obtained for the transiting exoplanet HAT-P-32b. The transits have been observed using several telescopes mainly throughout the YETI network. In 25 cases, complete transit light curves with a timing precision better than $1.4\:$min have been obtained. These light curves have been used to refine the system properties, namely inclination $i$, planet-to-star radius ratio $R_\textrm{p}/R_\textrm{s}$, and the ratio between the semimajor axis and the stellar radius $a/R_\textrm{s}$. First analyses by Hartman et al. (2011) suggest the existence of a second planet in the system, thus we tried to find an additional body using the transit timing variation (TTV) technique. Taking also literature data points into account, we can explain all mid-transit times by refining the linear ephemeris by 21ms. Thus we can exclude TTV amplitudes of more than $\sim1.5$min.