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X-ray emission from Lindroos binary systems

N. Huelamo·R. Neuhaeuser·B. Stelzer·R. Supper·H. Zinnecker
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Abstract

We present a study of the X-ray emission from binary systems extracted from the Lindroos catalogue (Lindroos 1986) based on the ROSAT All-Sky survey as well as ROSAT PSPC and HRI pointings. The studied sample consists of visual binary systems comprised of early-type primaries and late-type secondaries. The ages of the systems were determined by Lindroos (1985) from uvbybeta photometry of the primaries. These ages range between 33 and 135 Myr, so if the late-type secondaries are physically bound to the early-type primaries, they could be Post-T Tauri stars (PTTS). We have found strong X-ray emission from several secondaries. This fact together with their optical and IR data, make them bona fide PTTS candidates. We have also detected X-ray emission from several early-type primaries and, in particular, from most of the late-B type stars. Because their HRI hardness ratios are similar to those from resolved late-type stars, the presence of an unresolved late-type companion seems to be the cause of this emission.

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N. Huelamo, R. Neuhaeuser, B. Stelzer, R. Supper, H. Zinnecker. 2000-05-17. X-ray emission from Lindroos binary systems. https://arxiv.org/abs/astro-ph/0005348

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