The discovery of a luminous, rapidly oscillating Ap star, HD 116114, with a 21-minute pulsation period

• Published in: Monthly notices of the Royal Astronomical Society Vol. 358; no. 2; pp. 665 - 670
• Main Authors: Elkin, V. G., Riley, J. D., Cunha, M. S., Kurtz, D. W., Mathys, G.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01-04-2005; Blackwell Science
• Subjects: stars: individual: HD 116114; stars: magnetic fields; stars: oscillations; stars: variables: other; stars: oscillations; stars: magnetic fields; Luminosity; Stellar abundance; Magnetic stars; Radial velocity; stars: variables: other; stars: individual: HD 116114; Magnetic fields; Ap stars
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1111/j.1365-2966.2005.08830.x

The discovery of a new rapidly oscillating Ap star, HD 116114, with a pulsation period of 21 min, using high-resolution spectra obtained with the Ultraviolet-Visual Echelle Spectrograph at the European Southern Observatory's Very Large Telescope, is presented. The highest amplitudes of the radial velocity variations are between 50 and 125 m s−1 visible in the Eu ii lines. The spectral lines of La ii and the core of the Hα line have amplitudes of about 30 m s−1. The frequency obtained for the oscillations is in good agreement with theoretical predictions of longer-period, evolved roAp stars. The distinction in luminosity between the roAp and noAp stars, and the suggestion that in all roAp stars the abundance of the second ions of Pr and Nd, relative to the abundance of the first ions, is anomalously high, need to be revised in the light of this discovery.