Bibcode
dall, T. H.; Schmidtobreick, L.; Santos, N. C.; Israelian, G.
Bibliographical reference
Astronomy and Astrophysics, Volume 438, Issue 1, July IV 2005, pp.317-324
Advertised on:
7
2005
Journal
Citations
7
Refereed citations
6
Description
We present high resolution spectroscopy of the common proper motion
system FH Leo (components HD 96273 and BD+07 2411B), which has been
classified as a novalike variable due to an outburst observed by
Hipparcos, and we present and review the available photometry. We show
from our spectra that neither star can possibly be a cataclysmic
variable, instead they are perfectly normal late-F and early-G stars. We
measured their radial velocities and derived the atmospheric fundamental
parameters, abundances of several elements including Fe, Ni, Cr, Co, V,
Sc, Ti, Ca and Mg, and we derive the age of the system. From our
analysis we conclude that the stars do indeed constitute a physical
binary. However, the observed outburst cannot be readily explained. We
examine several explanations, including pollution with scattered light
from Jupiter, binarity, microlensing, background supernovae, interaction
with unseen companions and planetary engulfment. While no explanation is
fully satisfactory, the scattered light and star-planet interaction
scenarios emerge as the least unlikely ones, and we give suggestions for
further study.