Bibcode
Lazaro, C.; Arevalo, M. J.; Claret, A.
Referencia bibliográfica
Monthly Notices of the Royal Astronomical Society, Volume 334, Issue 3, pp. 542-552.
Advertised on:
8
2002
Número de citas
9
Número de citas referidas
9
Descripción
We present the first infrared (IR) light curves in the J, H and K bands
of δ Lib obtained at different observing runs from 1994 to 1998.
These IR light curves, showing a secondary minimum much deeper than in
visual bands, have been analysed in order to determine a new set of
physical parameters. A new program using the Roche geometry, and stellar
surface brightness from ATLAS model atmospheres, has been used in the
analysis and allows us to determine the physical parameters and the
distance of the binary. We compare these results with the Hipparcos
parallax, with the spectroscopic masses of the components derived from
the radial velocity curves, and with evolutionary stellar model
predictions. The adoption of a mass M1~= 2.85
Msolar for the primary star would remove the discrepancies
between our results and the Hipparcos distance, and the unusual location
of the δ Lib components in the Teff- log g diagram. Our
photometric analysis suggests that the stellar masses in δ Lib
could be overestimated, casting doubt on the claim that the primary
component of the system is overmassive and oversized compared with
single main-sequence stars of similar masses.