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CCD-based observations of PG 0856+121 and a theoretical analysis of its oscillation modes

A. Ulla·M. R. Zapatero Osorio·F. Perez Hernandez·J. MacDonald
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Abstract

BVRI CCD-based and near-IR (J) imaging, together with unfiltered photometry of the hot subdwarf B star PG 0856+121 are reported. Two close, faint, red, point-like sources are resolved. They account for the previously reported IR excess observed in this hot subdwarf. In addition, the new unfiltered differential photometry of PG 0856+121 confirms its previously reported pulsational nature. A comparison with the oscillation modes of stellar models suggests the possible presence of g modes.

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A. Ulla, M. R. Zapatero Osorio, F. Perez Hernandez, J. MacDonald. 2001-02-08. CCD-based observations of PG 0856+121 and a theoretical analysis of its oscillation modes. https://doi.org/10.1051/0004-6361%3A20010181

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