Theoretical Zero Age Main Sequences revisited
Astrophysics
2007-05-23 v1
Abstract
Zero Age Main Sequence (ZAMS) models with updated physical inputs are presented for selected assumptions about the chemical composition, covering the ranges 0.6 < M/Mo < 1.2, 0.0001 < Z < 0.04, 0.23 < Y < 0.34.The HR diagram location of the ZAMS as a function of Y and Z is discussed both in the theoretical and in the observational HR diagrams, showing that the V magnitude presents an increased dependence on Z to be taken into account when discussing observational evidences. Analytical relations quantifying both these dependences are derived. Implications for the galactic helium to heavier elements enrichment are finally discussed.
Cite
@article{arxiv.astro-ph/9908291,
title = {Theoretical Zero Age Main Sequences revisited},
author = {V. Castellani and S. Degl' Innocenti and M. Marconi},
journal= {arXiv preprint arXiv:astro-ph/9908291},
year = {2007}
}
Comments
4 pages, 4 postscript figures, accepted for publication on Astronomy & Astrophysics