The Open UniversitySkip to content

Pulsation versus metallicism in Am stars as revealed by LAMOST and WASP

Smalley, B.; Antoci, V.; Holdsworth, D. L.; Kurtz, D. W.; Murphy, S. J.; De Cat, P.; Anderson, D. R.; Catanzaro, G.; Cameron, A. Collier; Hellier, C.; Maxted, P. F. L.; Norton, A. J.; Pollacco, D.; Ripepi, V.; West, R. G. and Wheatley, P. J. (2017). Pulsation versus metallicism in Am stars as revealed by LAMOST and WASP. Monthly Notices of the Royal Astronomical Society, 465(3) pp. 2662–2670.

Full text available as:
PDF (Version of Record) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (1MB) | Preview
DOI (Digital Object Identifier) Link:
Google Scholar: Look up in Google Scholar


We present the results of a study of a large sample of A and Am stars with spectral types from LAMOST and light curves from WASP. We find that, unlike normal A stars, δ Sct pulsations in Am stars are mostly confined to the effective temperature range 6900 <Teff <7600 K. We find evidence that the incidence of pulsations in Am stars decreases with increasing metallicism (degree of chemical peculiarity). The maximum amplitude of the pulsations in Am stars does not appear to vary significantly with metallicism. The amplitude distributions of the principal pulsation frequencies for both A and Am stars appear very similar and agree with results obtained from Kepler photometry. We present evidence that suggests turbulent pressure is the main driving mechanism in pulsating Am stars, rather than the κ-mechanism, which is expected to be suppressed by gravitational settling in these stars.

Item Type: Journal Item
Copyright Holders: 2016 The Authors
ISSN: 1365-2966
Keywords: asteroseismology – techniques; photometric – stars; chemically peculiar – stars; oscillations – stars; variables: δ Scuti
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Physical Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Item ID: 48826
Depositing User: Andrew Norton
Date Deposited: 07 Mar 2017 10:45
Last Modified: 29 Jun 2020 13:54
Share this page:


Altmetrics from Altmetric

Citations from Dimensions

Download history for this item

These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.

Actions (login may be required)

Policies | Disclaimer

© The Open University   contact the OU