Open AccessPulsations in the atmosphere of the rapidly oscillating star 33 Lib ★ †
Author(s) -
Sachkov M.,
Hareter M.,
Ryabchikova T.,
Wade G.,
Kochukhov O.,
Shulyak D.,
Weiss W. W.
Publication year - 2011
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2011.19219.x
Subject(s) - physics , spectrograph , photometry (optics) , astrophysics , stars , asteroseismology , spectral line , astronomy , observatory , radial velocity , telescope , spectroscopy , very large telescope , space telescope imaging spectrograph , hubble space telescope
In 2009, the rapidly oscillating peculiar A‐type (roAp) star 33 Lib was the target of an intense observing campaign, combining ground‐based spectroscopy with space photometry obtained with the Microvariability and Oscillation of STars ( MOST ) satellite. We collected 780 spectra using the Echelle Spectro Polarimetric Device for the Observation of Stars (ESPaDOnS) spectrograph attached at the 3.6‐m Canada–France–Hawaii Telescope and 374 spectra with the Fibre‐fed Echelle Spectrograph attached at the 2.56‐m Nordic Optical Telescope to perform time‐resolved spectroscopy of 33 Lib. In addition, we used 111 Ultraviolet and Visual Echelle Spectrograph (UVES) spectra (2004) from the European Southern Observatory archive to check mode stability. Frequency analysis of the new radial velocity (RV) measurements confirms the previously reported frequency pattern (two frequencies and the first harmonic of the main one) and reveals an additional frequency at 1.991 mHz. The new frequency solution perfectly reproduces the RV variations from the 2004 and 2009 observational sets, providing strong support for p mode stability in this roAp star over at least 5 years.