The Appearance and Disappearance of Exocomet Gas Absorption
Joint Authors
Welsh, Barry Y.
Montgomery, Sharon L.
Source
Issue
Vol. 2015, Issue 2015 (31 Dec. 2015), pp.1-20, 20 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2015-09-13
Country of Publication
Egypt
No. of Pages
20
Main Subjects
Abstract EN
CaII K-line (3933 Å) absorption profiles observed towards 15 A-type and two B-type stars with known (or suspected) debris disks, in addition to archival spectral data for three A-type stars, are presented.
Inspection of the extracted CaII K-line absorption lines has determined that one late B-type (HD 58647) and four new A-type (HD 56537, HD 64145, HD 108767, and HD 109573) stellar systems exhibit short-term (night-to-night) absorption variation within these profiles.
This variability is due to the liberation of gas from falling evaporating bodies (the so-called FEBs activity) on the grazing approach of exocomets towards their parent star.
Also we present archival spectra of the FeI λ3860 Å and CaII K-lines towards β Pictoris (HD 39060) that, for the first time, reveal the absorption signatures of FEB activity at similar velocities in both line profiles.
FEB-hosting stars seem to be of an earlier type (on average spectral type Al.8 as compared with A3.1) than those where no FEB activity has been observed.
This could be due to stellar activity levels (such as chromospheric activity or nonradial pulsations) being of a higher level within the atmospheres of these hotter A-type stars.
American Psychological Association (APA)
Welsh, Barry Y.& Montgomery, Sharon L.. 2015. The Appearance and Disappearance of Exocomet Gas Absorption. Advances in Astronomy،Vol. 2015, no. 2015, pp.1-20.
https://search.emarefa.net/detail/BIM-1051983
Modern Language Association (MLA)
Welsh, Barry Y.& Montgomery, Sharon L.. The Appearance and Disappearance of Exocomet Gas Absorption. Advances in Astronomy No. 2015 (2015), pp.1-20.
https://search.emarefa.net/detail/BIM-1051983
American Medical Association (AMA)
Welsh, Barry Y.& Montgomery, Sharon L.. The Appearance and Disappearance of Exocomet Gas Absorption. Advances in Astronomy. 2015. Vol. 2015, no. 2015, pp.1-20.
https://search.emarefa.net/detail/BIM-1051983
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-1051983