CoRoT 102749568: Mode identification in a δ Scuti star based on regular spacings

Context. The high accuracy of space data increased the number of the periodicities determined for pulsating variable stars, but the mode identification is still a critical point in the non-asymptotic regime. Aims. We use regularities in frequency spacings for identifying the pulsation modes of the r...

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Detalhes bibliográficos
Autores: Paparo, M., Bognár, Z., Benko, JM, Gandolfi, D., Moya-Bedón, Andrés, Suárez, Juan Carlos, Sódor, A., Hareter, M., Poretti, E., Guenther, E. W., Auvergne, M., Baglin, A., Weiss, WW
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2013
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/404193
Acesso em linha:http://hdl.handle.net/10261/404193
Access Level:acceso abierto
Palavra-chave:Space vehicles
Stars: individual: CoRoT 102749568
Stars: interiors
Stars: oscillations
Stars: variables:δScuti
Descrição
Resumo:Context. The high accuracy of space data increased the number of the periodicities determined for pulsating variable stars, but the mode identification is still a critical point in the non-asymptotic regime. Aims. We use regularities in frequency spacings for identifying the pulsation modes of the recently discovered δ Sct star ID 102749568. Methods. In addition to analysing CoRoT light curves (15 252 datapoints spanning 131 days), we obtained and analysed both spectroscopic and extended multi-colour photometric data. We applied standard tools (MUFRAN, Period04, SigSpec, and FAMIAS) for time-series analysis. Results. A satisfactory light-curve fit was obtaining by means of 52 independent modes and 15 combination terms. The frequency spacing revealed distinct peaks around large (25.55-31.43 μHz), intermediate (9.80, 7.66 μHz), and low (2.35 μHz) separations. We directly identified 9 modes, and the l and n values of other three modes were extrapolated. The combined application of spectroscopy, multi-colour photometry, and modelling yielded the precise physical parameters and confirmed the observational mode identification. The large separation constrained the log g and related quantities. The dominant mode is the radial first overtone. © ESO, 2013.