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X-Ray Evidence for Flare Density Variations and Continual Chromospheric Evaporation in Proxima Centauri

Manuel Guedel·Marc Audard·Stephen L. Skinner·Matthias I. Horvath
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Abstract

Using the XMM-Newton X-ray observatory to monitor the nearest star to the Sun, Proxima Centauri, we recorded the weakest X-ray flares on a magnetically active star ever observed. Correlated X-ray and optical variability provide strong support for coronal energy and mass supply by a nearly continuous sequence of rapid explosive energy releases. Variable emission line fluxes were observed in the He-like triplets of OVII and NeIX during a giant flare. They give direct X-ray evidence for density variations, implying densities between 2x10^{10} - 4x10^{11} cm^{-3} and providing estimates of the mass and the volume of the line-emitting plasma. We discuss the data in the context of the chromospheric evaporation scenario.

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Manuel Guedel, Marc Audard, Stephen L. Skinner, Matthias I. Horvath. 2002-10-22. X-Ray Evidence for Flare Density Variations and Continual Chromospheric Evaporation in Proxima Centauri. https://doi.org/10.1086/345404

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