Bibcode
Taylor, W. D.; Evans, Christopher J.; Simón-Díaz, S.; Sana, Hugues; Langer, Norbert; Smith, Nathan; Smartt, Stephen J.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 442, Issue 2, p.1483-1490
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8
2014
Citations
14
Refereed citations
14
Description
The blue supergiant Sher 25 is surrounded by an asymmetric,
hourglass-shaped circumstellar nebula, which shows similarities to the
triple-ring structure seen around SN 1987A. From optical spectroscopy
over six consecutive nights, we detect periodic radial velocity
variations in the stellar spectrum of Sher 25 with a peak-to-peak
amplitude of ˜12 km s-1 on a time-scale of about 6 d,
confirming the tentative detection of similar variations by Hendry et
al. From consideration of the amplitude and time-scale of the signal,
coupled with observed line profile variations, we propose that the
physical origin of these variations is related to pulsations in the
stellar atmosphere, rejecting the previous hypothesis of a massive,
short-period binary companion. The radial velocities of two other blue
supergiants with similar bipolar nebulae, SBW1 and HD 168625, were also
monitored over the course of six nights, but these did not display any
significant radial velocity variations.
Related projects
The IACOB project: A new Era in the Study of Galactic OB Stars
IACOB is an ambitious long-term project whose main scientific goal is to provide an unprecedented empirical overview of the main physical properties of Galactic massive O- and B-type stars which can be used as definitive anchor point for our theories of stellar atmospheres, winds, interiors and evolution of massive stars
Sergio
Simón Díaz