English

Empirical calibration of the \lambda 4000 \AA break

Astrophysics 2009-10-31 v1

Abstract

Empirical fitting functions, describing the behaviour of the \lambda 4000 \AA break, D_4000, in terms of effective temperature, metallicity and surface gravity, are presented. For this purpose, the break has been measured in 392 stars from the Lick/IDS Library. We have followed a very detailed error treatment in the reduction and fitting procedures, allowing for a reliable estimation of the break uncertainties. This calibration can be easily incorporated into stellar population models to provide accurate predictions of the break amplitude for, relatively old, composite systems.

Cite

@article{arxiv.astro-ph/9905264,
  title  = {Empirical calibration of the \lambda 4000 \AA break},
  author = {Javier Gorgas and Nicolas Cardiel and Santos Pedraz and Jesus Gonzalez},
  journal= {arXiv preprint arXiv:astro-ph/9905264},
  year   = {2009}
}

Comments

21 pages including 7 postscript figures. Accepted for publication in Astronomy in Astrophysics Supplement Series. Table 1 will be also available at CDS

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