On the period and nature of the light and radial-velocity variations of HD 25799

Abstract

Reanalysis of the published radial velocities of the supposed spectroscopic binary HD 25799 shows that its period is 0.9121679 day rather than the 10.67 days found by Blaauw and van Albada (1963). We have obtained new photometric observations of this star during the period 1981-87. Comparison of light curves formed from these observations with each other and with light curves formed from archival data shows that the amplitude and possibly the shape of the light curve are variable. These changes cannot be explained by a binary star model. The similarity of the light and velocity variations to those of B stars that are believed to be nonradial pulsators argues that HD 25799 is a member of this group.

Radial velocities of early-type stars in the Perseus OB2 association

“…BvA's discovery of "erratic velocity changes" was in fact the first indication that this object is not a normal binary. Morris et al (1988) showed that an improved ephemeris (notably P = 0.9121679 d) could fit all previous spectroscopic data, but also showed, based on new photometric data, that the object is not a binary but a nonradial pulsator. This finding was confirmed later by Hipparcos photometry.…”

“…T Morris et al (1988); this is a non-radial pulsator; HD 25833: Giménez & Clausen (1994) (cf. Popper 1974.…”