Bibcode
DOI
Lázaro, C.; Arévalo, M. J.; Martínez-Pais, I. G.; Domínguez, R. M.
Referencia bibliográfica
The Astronomical Journal, Volume 123, Issue 5, pp. 2733-2743.
Fecha de publicación:
5
2002
Número de citas
12
Número de citas referidas
11
Descripción
We present the first light curves in the infrared J and K filters of VV
UMa and analyze them, together with a new set of BVR light curves
obtained in different runs from 1997 to 2000. Based on the spectra of VV
UMa and standard stars in the region 8440-8870 Å, we classify the
primary component of the binary as a type A1.5-2 V star. Evidence of
periodic small-amplitude variations in the brightness of the system is
found and is more clear during the secondary eclipse orbital phases. A
periodicity of about 0.51 hr is in good agreement with a previous
finding based on Strömgren photometry, pointing to a real origin in
the system, presumably on low-amplitude pulsations of the primary star.
The analysis of the BVRJK light curves, using a code based on ATLAS
model atmospheres, yields new orbital and stellar parameters. We derive
effective temperatures Teff=9250+/-150 K and
Teff=5600+/-100 K for the primary and secondary star,
respectively. We challenge the current view that VV UMa is a system with
unusually low mass components for their spectral type, and an
alternative solution is proposed, allowing masses of the stars in the
expected range for their spectral types that are in reasonable agreement
with the available photometric and spectroscopic data. From the
visual-infrared photometry we find no evidence of a significant infrared
excess in the system, deriving an interstellar reddening
E(B-V)<=0.10.