The Mean Underabundances of Carbon and Aluminum Over the Surface of 21 Com from Its Far-ultraviolet Spectra Recorded by IUE
Open Access
- 8 October 2021
- journal article
- Published by American Astronomical Society in Research Notes of the AAS
- Vol. 5 (10), 226
- https://doi.org/10.3847/2515-5172/ac2d38
Abstract
The comparison of a coadded International Ultraviolet Explorer (IUE) far-ultraviolet spectrum of 21 Com (A3p SrCr) to that of the standard star α Psa (A3V) reveals large differences in the resonance and low-excitation lines of C i and Al ii. All the lines of these species are significantly weaker in the mean spectrum of 21 Com. The synthesis of these lines consistently yields sizable underabundances for 21 Com of about 0.5 times the solar carbon, and 0.20 times solar for aluminum. Inspection of 10 individual spectra taken over the 24 hr monitoring of 21 Com with IUE on 1991 April 17 does not reveal convincing variations of the lines analyzed here between rotational phases 0.18 and 0.65 of the 2 days period, suggesting a uniform repartition of these 2 elements over the hemisphere of 21 Com observed then.This publication has 3 references indexed in Scilit:
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