CCD - based observations of PG 0856 + 121 and a theoretical analysis of its oscillation modes ⋆
نویسندگان
چکیده
BV RI 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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تاریخ انتشار 2001