Fulltext

Short-period line profile and light variations in the Beta Cephei star 19 Monocerotis

Balona, L. A. ; James, D. J. ; Motsoasele, P. ; Nombexeza, B. ; Ramnath, A. ; Van Dyk, J.

In: Monthly Notices of the Royal Astronomical Society, 2002, vol. 333, no. 4, p. 952-960

Add to personal list
    Title
    • Short-period line profile and light variations in the Beta Cephei star 19 Monocerotis
    Author
    • Balona, L. A.. South African Astronomical Observatory, PO Box 9, Observatory 7935, Cape Town, South Africa
    • James, D. J.. School of Physics and Astronomy, University of St Andrews, St Andrews
    • Motsoasele, P.. University of Cape Town, Private Bag, Rondebosch 7701, South Africa
    • Nombexeza, B.. University of Fort Hare, Private Bag X1314, Alice 5700, South Africa
    • Ramnath, A.. University of the Witwatersrand, Private Bag 3, WITS, 2050, South Africa
    • Van Dyk, J.. University of Pretoria, Pretoria 0002, South Africa
    Document Type
    • Postprint
    OAI-PMH Identifier
    • oai:doc.rero.ch:297096
    Summary
    We present an analysis of 555 high-dispersion echelle spectra of 19 Mon obtained from two sites as well as 115 Strömgren uvby observations. We show that three periodicities are present at 5.229 94, 0.170 19 and 4.889 56 cycle d−1. The first periodicity has by far the largest amplitude. Photometric amplitude ratios and phase differences indicate an ℓ=2 mode, while the line profile variations unequivocally point to ℓ=2,m=-2. Because of the low amplitudes of the other two modes, very little can be said concerning them. Although 19 Mon was originally selected on the basis of its classification as a marginal Be star, the Be nature of the star is not supported by our observations