Bibcode
Deka-Szymankiewicz, B.; Niedzielski, A.; Adamczyk, M.; Adamów, M.; Nowak, G.; Wolszczan, A.
Bibliographical reference
Astronomy and Astrophysics, Volume 615, id.A31, 11 pp.
Advertised on:
7
2018
Journal
Citations
25
Refereed citations
22
Description
Context. Our knowledge of the intrinsic parameters of exoplanets is as
precise as our determinations of their stellar hosts parameters. In the
case of radial velocity searches for planets, stellar masses appear to
be crucial. But before estimating stellar masses properly, detailed
spectroscopic analysis is essential. With this paper we conclude a
general spectroscopic description of the Pennsylvania-Toruń
Planet Search (PTPS) sample of stars. Aims: We aim at a detailed
description of basic parameters of stars representing the complete PTPS
sample. We present atmospheric and physical parameters for dwarf stars
observed within the PTPS along with updated physical parameters for the
remaining stars from this sample after the first Gaia data release. Methods: We used high resolution (R = 60 000) and high
signal-to-noise-ratio (S/N = 150-250) spectra from the Hobby-Eberly
Telescope and its High Resolution Spectrograph. Stellar atmospheric
parameters were determined through a strictly spectroscopic local
thermodynamic equilibrium analysis (LTE) of the equivalent widths of Fe
I and Fe II lines. Stellar masses, ages, and luminosities were estimated
through a Bayesian analysis of theoretical isochrones. Results:
We present Teff, log g, [Fe/H], microturbulence velocities,
absolute radial velocities, and rotational velocities for 156 stars from
the dwarf sample of PTPS. For most of these stars these are the first
determinations. We refine the definition of PTPS subsamples of stars
(giants, subgiants, and dwarfs) and update the luminosity classes for
all PTPS stars. Using available Gaia and HIPPARCOS parallaxes, we
redetermine the stellar parameters (masses, radii, luminosities, and
ages) for 451 PTPS stars. Conclusions: The complete PTPS sample
of 885 stars is composed of 132 dwarfs, 238 subgiants, and 515 giants,
of which the vast majority are of roughly solar mass; however, 114 have
masses higher than 1.5 M⊙ and 30 of over 2
M⊙. The PTPS extends toward much less metal abundant and
much more distant stars than other planet search projects aimed at
detecting planets around evolved stars; 29% of our targets belong to the
Galactic thick disc and 2% belong to the halo.
Based on observations obtained with the Hobby-Eberly Telescope, which is
a joint project of the University of Texas at Austin, Pennsylvania State
University, Stanford University, Ludwig-Maximilians-Universität
München, and Georg-August-Universität Göttingen.Tables
2-4 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr
(ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/615/A31
Related projects
Exoplanets and Astrobiology
The search for life in the universe has been driven by recent discoveries of planets around other stars (known as exoplanets), becoming one of the most active fields in modern astrophysics. The growing number of new exoplanets discovered in recent years and the recent advance on the study of their atmospheres are not only providing new valuable
Enric
Pallé Bago