
The Absence of Far UV Variability in the IUE Spectra of ξ Oct (HD 215573)
Author(s) -
Richard Monier
Publication year - 2022
Publication title -
research notes of the aas
Language(s) - English
Resource type - Journals
ISSN - 2515-5172
DOI - 10.3847/2515-5172/ac64fc
Subject(s) - spectral line , ultraviolet , flux (metallurgy) , physics , astrophysics , absorption spectroscopy , far ultraviolet , astronomy , optics , chemistry , organic chemistry
The analysis of high resolution SWP spectra obtained through the large aperture with the International Ultraviolet Explorer reveals that the far-ultraviolet flux of ξ Oct did not vary. In particular, the flux remained stable in a series of seven spectra taken consecutively over 3 hr and 24 minutes. This time interval is much shorter than the 1.78 days rotational period proposed for this star from its TESS lightcurve, which could explain for the absence of variability in the FUV. The comparison of the STIS spectrum of ξ Oct in the range 1300–1340 Å with synthetic spectra computed for the fundamental parameters of ξ Oct and a solar composition allows the identification of the strongest absorption features in the far-ultraviolet as due to resonance lines of O i , Si ii and C ii .