We present the fundamental stellar and planetary properties of the transiting planetary system WASP-13 within the framework of the Homogeneous Study of Transiting Systems ( HoSTS ) .
HoSTS aims to derive the fundamental stellar ( T _ { eff } , [ Fe/H ] , M _ { \star } , R _ { \star } ) , and planetary ( M _ { pl } , R _ { pl } , T _ { eq } ) physical properties of known transiting planets using a consistent methodology and homogeneous high-quality dataset .
Four spectral analysis techniques are independently applied to a Keck+HIRES spectrum of WASP-13 considering two distinct cases : unconstrained parameters , and constrained \log g from transit light curves .
We check the derived stellar temperature against that from a different temperature diagnostic based on an INT+IDS H _ { \alpha } spectrum .
The four unconstrained analyses render results that are in good agreement , and provide an improvement of 50 % in the precision of T _ { eff } , and of 85 % in [ Fe/H ] with respect to the WASP-13 discovery paper .
The planetary parameters are then derived via the Monte-Carlo-Markov-Chain modeling of the radial velocity and light curves , in iteration with stellar evolutionary models to derive realistic uncertainties .
WASP-13 ( 1.187 \pm 0.065M _ { \odot } ; 1.574 \pm 0.048R _ { \odot } ) hosts a Saturn-mass , transiting planet ( 0.500 \pm 0.037M _ { Jup } ; 1.407 \pm 0.052R _ { Jup } ) , and is at the end of its main-sequence lifetime ( 4-5.5 Gyr ) .
Our analysis of WASP-13 showcases that both a detailed stellar characterization , and transit modeling are necessary to well determine the fundamental properties of planetary systems , which are paramount in identifying and determining empirical relationships between transiting planets and their hosts .