The discovery of lambda Bootis stars - the Southern Survey II
Article
Article Title | The discovery of lambda Bootis stars - the Southern Survey II |
---|---|
ERA Journal ID | 1074 |
Article Category | Article |
Authors | Murphy, Simon J. (Author), Gray, Richard O. (Author), Corbally, Christopher J. (Author), Kuehn, Charles (Author), Bedding, Timothy R. (Author) and Killam, Josiah (Author) |
Journal Title | Monthly Notices of the Royal Astronomical Society |
Journal Citation | 499 (2), pp. 2701-2713 |
Number of Pages | 13 |
Year | 2020 |
Publisher | Oxford University Press |
Place of Publication | United Kingdom |
ISSN | 0035-8711 |
1365-2966 | |
Digital Object Identifier (DOI) | https://doi.org/10.1093/mnras/staa2347 |
Web Address (URL) | https://academic.oup.com/mnras/article/499/2/2701/5891252 |
Abstract | The λ Boo stars are chemically peculiar A-type stars whose abundance anomalies are associated with the accretion of metal-poor material. We searched for λ Boo stars in the Southern hemisphere in a targeted spectroscopic survey of metal-weak and emission-line stars. Obtaining spectra for 308 stars and classifying them on the MK system, we found or co-discovered 24 new λ Boo stars. We also revised the classifications of 11 known λ Boo stars, one of which turned out to be a chemically normal rapid rotator. We show that stars previously classified in the literature as blue horizontal branch stars or emission-line A stars have a high probability of being λ Boo stars, although this conclusion is based on small-number statistics. Using WISE infrared fluxes, we searched our targets for infrared excesses that might be attributable to protoplanetary or debris discs as the source of the accreted material. Of the 34 λ Boo stars in our sample, 21 at various main-sequence ages have infrared excesses, confirming that not all λ Boo stars are young. |
Keywords | stars: chemically peculiar; circumstellar matter; stars: early-type; stars: emission-line, Be; stars: evolution; Astrophysics - Solar and Stellar Astrophysics |
ANZSRC Field of Research 2020 | 510109. Stellar astronomy and planetary systems |
Public Notes | This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2020 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. |
Byline Affiliations | University of Sydney |
Appalachian State University, United States | |
University of Arizona, United States | |
Institution of Origin | University of Southern Queensland |
https://research.usq.edu.au/item/q73q7/the-discovery-of-lambda-bootis-stars-the-southern-survey-ii
Download files
Published Version
The discovery of lambda Bootis stars - the Southern Survey II (Murphy et al. 2020c).pdf | ||
File access level: Anyone |
56
total views57
total downloads0
views this month2
downloads this month