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arXiv · 2308.07981

Stable Coronal X-Ray Emission Over Twenty Years of XZ Tau

Steven M. Silverberg·Hans Moritz Guenther·Pragati Pradhan·David A. Principe·P. C. Schneider·Scott J. Wolk
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Abstract

XZ Tau AB is a frequently observed binary YSO in the Taurus Molecular Cloud; XZ Tau B has been classified as an EXOr object. We present new Chandra/HETG-ACIS-S observations of XZ Tau AB, complemented with variability monitoring of the system with XMM-Newton, to constrain the variability of this system and identify high-resolution line diagnostics to better understand the underlying mechanisms that produce the X-rays. We observe two flares with XMM-Newton, but find that outside of these flares the coronal X-ray spectrum of XZ Tau AB is consistent over twenty years of observations. We compare the ensemble of XZ Tau X-ray observations over time with the scatter across stars observed in point-in-time observations of the Orion Nebula Cluster and find that both overlap in terms of plasma properties, i.e., some of the scatter observed in the X-ray properties of stellar ensembles stems from intrinsic source variability.

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Steven M. Silverberg, Hans Moritz Guenther, Pragati Pradhan, David A. Principe, P. C. Schneider, Scott J. Wolk. 2023-08-15. Stable Coronal X-Ray Emission Over Twenty Years of XZ Tau. https://arxiv.org/abs/2308.07981

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