The Delta Scuti star FG Vir. V. The 2002 photometric multisite campaign

Abstract

A high-accuracy multisite campaign was carried out from 2002 January to May with a photometric coverage of 398 hours at five observatories. The concentration on a few selected sites gives better consistency and accuracy than collecting smaller amounts from a larger number of sites. 23 frequencies were detected with a high statistical significance. 6 of these are new. The 17 frequencies found in common with the 1992-1995 data are the modes with highest amplitudes. This indicates that the pulsation spectrum of FG Vir is relatively stable over the ten-year period. Two frequencies have variable amplitudes and phases from year to year as well as during 2002. These were both found to be double modes with close frequencies. For the mode at 12.15 c/d this leads to an apparent modulation with a time scale of about 129d. The close frequencies at 12.15 c/d are composed of a radial and a nonradial mode, suggesting a similarity with the Blazhko Effect seen in RR Lyrae stars.

arXiv comment8 pages, 4 figures, 2 tables

References in corpus (2)

• Close frequency pairs in Delta Scuti stars
• Line profile analysis of the Delta Scuti star HD2724=BB Phe: mode identification and amplitude variations

Cited by in corpus (6)

• On the photometric detection of Internal Gravity Waves in upper main-sequence stars I. Methodology and application to CoRoT targets
• Detection of 75+ pulsation frequencies in the Delta Scuti star FG Vir
• A new method for the spectroscopic identification of stellar non-radial pulsation modes. II. Mode identification of the Delta Scuti star FG Virginis
• A precise asteroseismic age and metallicity for HD 139614: a pre-main-sequence star with a protoplanetary disc in Upper-Centaurus Lupus
• Inferences from pulsational amplitudes and phases for multimode $\delta$ Sct star FG Vir
• Amplitude variability or close frequencies in pulsating stars? The Delta Scuti star FG Vir