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Transiting planets around stars are discovered mostly through photometric surveys. Unlike radial velocity surveys, photometric surveys do not tend to target slow rotators, inactive or metal-rich stars. Nevertheless, we suspect that observational biases could also impact transiting-planet hosts. This paper aims to evaluate how selection effects reflect on the evolutionary stage of both a limited sample of transiting-planet host stars (TPH) and a wider sample of planet-hosting stars detected through radial velocity analysis. Then, thanks to uniform derivation of stellar ages, a homogeneous comparison between exoplanet hosts and field star age distributions is developed. Stellar parameters have been computed through our custom-developed isochrone placement algorithm, according to PARSEC models. The notable aspects of our algorithm include the treatment of element diffusion, activity checks in terms of $log{R_{HK}}$ and $vsin{i}$, and the evaluation of the stellar evolutionary speed in the Hertzsprung-Russel diagram in order to better constrain age. Working with TPH, the observational stellar mean density $rho_{star}$ allows us to compute stellar luminosity even if the distance is not available, by combining $rho_{star}$ with the spectroscopic $log{g}$. The median value of the TPH ages is $sim5$ Gyr. Even if this sample is not very large, however, the result is very similar to what we found for the sample of spectroscopic hosts, whose modal and median values are [3, 3.5) Gyr and $sim4.8$ Gyr, respectively. Thus, these stellar samples suffer almost the same selection effects. We also conclude that the age of our Sun is consistent with the age distribution of solar neighbourhood MS stars with spectral types from late F to early K, regardless of whether they harbour planets or not. We considered the possibility that our selected samples are older than the average disc population.
Exoplanet-host stars (EHS) are known to present surface chemical abundances different from those of stars without any detected planet (NEHS). EHS are, on the average, overmetallic compared to the Sun. The observations also show that, for cool stars,
The mean density of a star transited by a planet, brown dwarf or low mass star can be accurately measured from its light curve. This measurement can be combined with other observations to estimate its mass and age by comparison with stellar models. O
Aims:To support the computation and evolutionary interpretation of periods associated with the rotational modulation, oscillations, and variability of stars located in the CoRoT fields, we are conducting a spectroscopic survey for stars located in th
Stars with hot Jupiters tend to be rotating faster than other stars of the same age and mass. This trend has been attributed to tidal interactions between the star and planet. A constraint on the dissipation parameter $Q_star$ follows from the assump
We present a substantial extension of the mm-wave continuum photometry catalog for Taurus circumstellar dust disks. Combining new Submillimeter Array data with measurements in the literature, we construct a mm-wave luminosity distribution for Class I