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A new strongly X-ray flaring M9 dwarf in the solar neighborhood

V. Hambaryan·A. Staude·A. D. Schwope·R. -D. Scholz·S. Kimeswenger·R. Neuhäuser
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Abstract

We report on the discovery of a very low mass (VLM) star in the solar neighborhood, originally identified as an optical counterpart of a flaring X-ray source detected in the ROSAT All-Sky survey. Optical spectroscopy and infrared photometry consistently reveal a spectral type of M9 \pm 0.5 and a distance of ~11 pm 2pc. The optical counterpart of 1RXS J115928.5-524717 shows a large proper motion of 1.08\pm0.06 "/year. 1RXS~J115928.5-524717 is the fourth object among the VLM stars displaying a huge X-ray flare, reaching the unprecedent value of L_X/L_{bol}~0.1.

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V. Hambaryan, A. Staude, A. D. Schwope, R. -D. Scholz, S. Kimeswenger, R. Neuhäuser. 2003-11-03. A new strongly X-ray flaring M9 dwarf in the solar neighborhood. https://doi.org/10.1051/0004-6361%3A20034378

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