A photometric study of the light variations of the triple system DG Leo
Por:
Lampens P., Frémat Y., Garrido R., Peña J.H., Parrao L., Van Cauteren P., Cuypers J., De Cat P., Uytterhoeven K., Arentoft T., Hobart M.
Publicada:
1 ene 2005
Resumen:
Multi-site and multi-year differential photometry of the triple star DG Leo reveals a complex frequency spectrum that can be modelled as the combination of at least three ? Scuti type frequencies in the range 11.5-13 c/d (with semi-amplitudes of 2-7 mmag) and a superimposed slow variability of larger amplitude. The period of the slow variation fits very well with half the orbital period of the inner spectroscopic binary indicating the presence of ellipsoidal variations caused by the tidally deformed components in a close configuration. These findings, together with the results of a recent spectroscopic analysis (showing that the system consists of a pair of mild Am stars and one A-type component of normal solar composition), infer that DG Leo is an extremely interesting asteroseismic target. Identification of which component(s) of this multiple system is (or are) pulsating and determination of the excited pulsation modes will both contribute to a much better understanding of the non-trivial link between multiplicity, chemical composition, rotation, and pulsation in the lower part of the classical Cepheid instability strip. © ESO 2005.
Filiaciones:
Lampens P.:
Koninklijke Sterrenwacht Van België, Ringlaan 3, 1180 Brussel, Belgium
Frémat Y.:
Koninklijke Sterrenwacht Van België, Ringlaan 3, 1180 Brussel, Belgium
Garrido R.:
Instituto de Astrofísica de Andalucía, CSIC, Camino Bajo de Huetor, 18008 Granada, Spain
Peña J.H.:
Instituto de Astronomía, UNAM, Apartado Postal 70-264, Mexico 04510, DF, Mexico
Parrao L.:
Instituto de Astronomía, UNAM, Apartado Postal 70-264, Mexico 04510, DF, Mexico
Van Cauteren P.:
Beersel Hills Observatory, Laarheidestraat 166, 1650 Beersel, Belgium
Cuypers J.:
Koninklijke Sterrenwacht Van België, Ringlaan 3, 1180 Brussel, Belgium
De Cat P.:
Koninklijke Sterrenwacht Van België, Ringlaan 3, 1180 Brussel, Belgium
Institute of Astronomy, KU Leuven, Celestijnenlaan 200B, 3001 Leuven, Belgium
Uytterhoeven K.:
Institute of Astronomy, KU Leuven, Celestijnenlaan 200B, 3001 Leuven, Belgium
Arentoft T.:
Koninklijke Sterrenwacht Van België, Ringlaan 3, 1180 Brussel, Belgium
Department of Physics and Astronomy, Aarhus University, 8000 Aarhus C, Denmark
Hobart M.:
Facultad de Física, Universidad Veracruzana, Veracruz, Mexico
Bronze
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