English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We report on a spectroscopic determination of the atmospheric parameters andchemical abundance of the parent star of the recently discovered transitingplanet {TrES-2}. A detailed LTE analysis of a set of \ion{Fe}{1} and\ion{Fe}{2} lines from our Keck spectra yields $T_\mathrm{eff} = 5850\pm 50$ K,$\log g = 4.4\pm 0.1$, and [Fe/H] $= -0.15\pm 0.10$. Several independent checks(e.g., additional spectroscopy, line-depth ratios) confirm the reliability ofour spectroscopic $T_\mathrm{eff}$ estimate. The mass and radius of the star,needed to determine the properties of the planet, are traditionally inferred bycomparison with stellar evolution models using $T_\mathrm{eff}$ and somemeasure of the stellar luminosity, such as the spectroscopic surface gravity(when a trigonometric parallax is unavailable, as in this case). We apply herea new method in which we use instead of $\log g$ the normalized separation$a/R_\star$ (related to the stellar density), which can be determined directlyfrom the light curves of transiting planets with much greater precision. Withthe $a/R_\star$ value from the light curve analysis of Holman et al.\citeyearpar{holman07b} and our $T_\mathrm{eff}$ estimate we obtain $M_\star =0.980\pm0.062 M_\odot$ and $R_\star = 1.000_{-0.033}^{+0.036} R_\odot$, and anevolutionary age of $5.1^{+2.7}_{-2.3}$ Gyr, in good agreement with otherconstraints based on the strength of the emission in the \ion{Ca}{2} H & K linecores, the Lithium abundance, and rotation. The new stellar parameters yieldimproved values for the planetary mass and radius of $M_p = 1.198 \pm 0.053M_\mathrm{Jup}$ and $R_p = 1.220^{+0.045}_{-0.042} R_\mathrm{Jup}$, confirmingthat {TrES-2} is the most massive among the currently known nearby ($d\lesssim300$ pc) transiting hot Jupiters. [Abridged]

Improving Stellar and Planetary Parameters of Transiting Planet Systems: The Case of TrES-2