Discovery of $\delta$ Scuti pulsation in the Herbig Ae star VV Ser

Abstract

A new observational study of the Herbig Ae star VV Ser has been performed in order to detect and accurately measure pulsation frequencies in the $\delta$ Scuti range. As it belongs to the continuous field of view of the asteroseismological satellite COROT, this study also aims at characterizing the properties of VV Ser as a potential ``COROT additional program'' candidate. CCD time series photometry in the Johnson V filter has been obtained during three consecutive years. The resulting light curves have been subject to detailed frequency analysis and the derived frequencies have been compared to model predictions. Seven pulsation frequencies have been measured on the basis of the best dataset obtained in 2004, ranging from $\sim$ 31 to $\sim$ 118 $\mu Hz$, with an accuracy of the order of 0.5 $\mu Hz$. The comparison with an extensive set of asteroseismological models shows that all the observed periodicities can be reproduced if the stellar mass is close to $4M_{\odot }$. Conversely, the measured frequencies can be associated to $p$ modes only if the effective temperature is significantly lower than that obtained from the spectral type conversion. The present results seem to suggest that more accurate spectral type determination is necessary in order to discriminate the best fit model solution. In any case, the stellar mass of VV Ser is close to the upper mass limit ($\sim 4M_{\odot }$) for this class of pulsators.

A&A Accepted, 10 pages + 4 pages online material

References in corpus (8)

• ISO spectroscopy of disks around Herbig Ae/Be stars
• Acoustic oscillations of rapidly rotating polytropic stars. II. Effects of the Coriolis and centrifugal accelerations
• The Instability Strip for Pre--Main-Sequence Stars
• Comparative seismology of pre- and main sequence stars in the instability strip
• A multisite photometric campaign on the Pre-Main-Sequence delta Scuti pulsator IP Per
• The role of the time step and overshooting in the modelling of PMS evolution: the case of EK Cephei
• Multisite observations of the PMS delta Scuti star V351 Ori
• Detection of delta Scuti-like pulsation in H254, a pre-main sequence F-type star in IC 348

Cited by in corpus (7)

• Parameters of Herbig Ae/Be and Vega-type stars
• Comparing the observational instability regions for pulsating pre-main sequence and classical $\delta$ Scuti stars
• Grids of stellar evolution models for asteroseismology (CESAM + POSC)
• The Arizona Radio Observatory CO Mapping Survey of Galactic Molecular Clouds: III. The Serpens Cloud in CO J=2-1 and 13CO J=2-1 Emission
• Matching the frequency spectrum of PMS stars by means of standard and rotating models
• Searching for $\delta$ Scuti-type pulsation and characterising northern pre-main-sequence field stars
• Seismic evolution of low/intermediate mass PMS stars