N. Mowlavi, P. Eggenberger, G. Meynet, S. Ekstrom, C. Georgy, A. Maeder, C. Charbonnel, L. Eyer
We present dense grids of stellar models suitable for comparison with
observable quantities measured with great precision, such as those derived from
binary systems or planet-hosting stars. We computed new Geneva models without
rotation at metallicities Z=0.006, 0.01, 0.014, 0.02, 0.03 and 0.04 (i.e.
[Fe/H] from -0.33 to +0.54) and with mass in small steps from 0.5 to 3.5 Msun.
Great care was taken in the procedure for interpolating between tracks in order
to compute isochrones. Several properties of our grids are presented as a
function of stellar mass and metallicity. Those include surface properties in
the Hertzsprung-Russell diagram, internal properties including mean stellar
density, sizes of the convective cores, and global asteroseismic properties. We
checked our interpolation procedure and compared interpolated tracks with
computed tracks. The deviations are less than 1% in radius and effective
temperatures for most of the cases considered. We also checked that the present
isochrones provide nice fits to four couples of observed detached binaries and
to the observed sequences of the open clusters NGC 3532 and M67. Including
atomic diffusion in our models with M<1.1 Msun leads to variations in the
surface abundances that should be taken into account when comparing with
observational data of stars with measured metallicities. For that purpose,
iso-Zsurf lines are computed. These can be requested for download from a
dedicated web page together with tracks at masses and metallicities within the
limits covered by the grids. The validity of the relations linking Z and FeH is
also re-assessed in light of the surface abundance variations in low-mass
stars.
View original:
http://arxiv.org/abs/1201.3628
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