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arXiv · 1203.3242

Soft coronal X-rays from \beta{} Pictoris

H. M. Günther·S. J. Wolk·J. J. Drake·C. M. Lisse·J. Robrade·J. H. M. M. Schmitt
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Abstract

A type stars are expected to be X-ray dark, yet weak emission has been detected from several objects in this class. We present new Chandra/HRC-I observations of the A5 V star \beta{} Pictoris. It is clearly detected with a flux of 9+-2 10^{-4} counts/s. In comparison with previous data this constrains the emission mechanism and we find that the most likely explanation is an optically thin, collisionally dominated, thermal emission component with a temperature around 1.1 MK. We interpret this component as a very cool and dim corona, with \log L_X/L_{bol}=-8.2 (0.2-2.0 keV). Thus, it seems that \beta{} Pictoris shares more characteristics with cool stars than previously thought.

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H. M. Günther, S. J. Wolk, J. J. Drake, C. M. Lisse, J. Robrade, J. H. M. M. Schmitt. 2012-03-15. Soft coronal X-rays from \beta{} Pictoris. https://doi.org/10.1088/0004-637x/750/1/78

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