2003/05/28 by H. Kjeldsen, T. R. Bedding, I. K. Baldry +10 · 1 citation
Physics and Astronomy · #Amplitude #Astronomy and Astrophysical Research #Measure (data warehouse) #Observatory #Oscillation (cell signaling) #Solar and Space Plasma Dynamics #Spectral line #Spectroscopy #Stellar, planetary, and galactic studies #Subgiant #astro-ph
paper · pdf · doi:10.1086/377315
published as Astron.J. 126 (2003) 1483 · 18 pages, LaTeX with figures. Accepted for publication by AJ
arxiv created 2003/05/28 · openalex publication_date 2003/08/29 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We obtained time-series spectroscopy of the G0 subgiant η Boo in an attempt to confirm the solar-like oscillations reported by Kjeldsen and coworkers in 1995. We recorded 1843 spectra over six consecutive nights with the Nordic Optical Telescope, which we used to measure equivalent widths of strong temperature-sensitive lines. We also measured velocities from 1989 spectra obtained through an iodine reference cell at Lick Observatory over 56 nights that were badly affected by weather. Our analysis also included velocity measurements published by Brown and coworkers and the original Kjeldsen equivalent width measurements. All four data sets show power excesses consistent with oscillations, although with a range of amplitudes that presumably reflects the stochastic nature of the excitation. The highest peaks show regularity with a large separation of Δν = 40.4 μHz, and we identify 21 oscillation frequencies from the combined data.