C. Saffe
Instituto de Ciencias Astronómicas, de la Tierra y del Espacio (ICATE), C.C 467, 5400, San Juan, Argentina. Member of the Carrera del Investigador Científico, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) de la República Argentina (csaffe@icate–conicet.gob.ar).
Received 2 July 2010
Accepted 14 September 2010
RESUMEN
]]> Implementamos un programa en Fortran que determina parámetros fundamentales de estrellas de tipo solar, a partir de anchos equivalentes del Fe. La solución debe verificar tres condiciones en el método estándar: equilibrio de ionización, equilibrio de excitación e independencia entre abundancias y anchos equivalentes. Calculamos modelos de atmósfera de Kurucz con opacidades NEWODF. Detalles como el parámetro de longitud de mezcla, el sobre impulso convectivo, etc. se calculan con un programa independiente. FUNDPAR calcula las incertezas por dos métodos: el criterio de Gonzalez & Vanture (1998) y utilizando la función χ2 . Los resultados derivados con FUNDPAR están de acuerdo con determinaciones previas en la literatura. En particular obtuvimos parámetros fundamentales de 58 estrellas con exoplanetas. El programa está disponible en la red1.
ABSTRACT
We implemented a Fortran code that determines fundamental parameters of solar type stars from a list of Fe line equivalent widths. The solution should verify three conditions in the standard method: ionization equilibrium, excitation equilibrium and independence between metallicity and equivalent widths. Solarscaled Kurucz model atmospheres with NEWODF opacities are calculated with an independent program. Parameter files control different details, such as the mixinglength parameter and the overshooting. FUNDPAR derives the uncertainties following two methods: the criterion of Gonzalez & Vanture (1998) and the dispersion using the χ2 function. The code uses the 2009 version of the MOOG program. The results derived with FUNDPAR are in agreement with previous determinations in the literature. The program is freely available from the web1.
Key Words: stars: abundances — stars: fundamental parameters.
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ACKNOWLEDGMENTS
The author thank R. L. Kurucz, C. Sneden, L. Sbordone, P. Bonifacio and F. Castelli for making their codes available to him. We also thank the anonymous referee whose suggestions improved the paper. This work was partially supported by agrant PIP 1153 from Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina.
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1 http://icate–conicet.gob.ar/saffe/fundpar/.
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