Bibcode
Oreiro, R.; Pérez Hernández, F.; Ulla, A.; Garrido, R.; Østensen, R.; MacDonald, J.
Bibliographical reference
Astronomy and Astrophysics, Volume 438, Issue 1, July IV 2005, pp.257-263
Advertised on:
7
2005
Journal
Citations
50
Refereed citations
40
Description
We report the discovery of long period oscillations in the light curve
of the bright sdB pulsator Balloon 090100001. We find at least three
peaks in the low frequency amplitude spectrum of the star (at periods
2733, 3665, 4378 s) and 10 certain frequencies in the short period range
(118-356 s), but probably more than 25 frequencies modulate the light
curve of this object. This star is one of only two sdBs, together with
HS 0702+6043, known to show simultaneously short and long period
pulsations. We also discuss the results of a set of multicolour
photometric observations of the target, for which an amplitude-phase
diagram is possible for the two dominant peaks. Comparision with
theoretical models indicate that the short period peaks correspond to p
modes clustered around the fundamental and the first three overtones,
while the long period peaks correspond to g modes of high radial order.