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arXiv · 2404.09361

Initial results of our spectro-photometric monitoring of XZ Tau

Arpan Ghosh·Saurabh Sharma·Joe Philip Ninan·Devendra K. Ojha·Aayushi Verma·Tarak Chand Sahu·Rakesh Pandey·Koshvendra Singh
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Abstract

We present here initial results of our spectro-photometric monitoring of XZ Tau. During our monitoring period, XZ Tau exhibited several episodes of brightness variations in timescales of months at optical wavelengths in contrast to the mid-infrared wavelengths. The color evolution of XZ Tau during this period suggest that the brightness variations are driven by changes in accretion from the disc. The mid-infrared light curve shows an overall decline in brightness by $\sim$ 0.5 and 0.7 magnitude respectively in WISE W1 (3.4 $\mu$m) and W2 (4.6 $\mu$m) bands. The emission profile of the hydrogen recombination lines along with that of Ca II IRT lines points towards magnetospheric accretion of XZ Tau. We have detected P Cygni profile in H$\beta$ indicating of outflowing winds from regions close to accretion. Forbidden transitions of oxygen are also detected, likely indicating of jets originating around the central pre-main sequence star.

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Arpan Ghosh, Saurabh Sharma, Joe Philip Ninan, Devendra K. Ojha, Aayushi Verma, Tarak Chand Sahu, Rakesh Pandey, Koshvendra Singh. 2024-04-14. Initial results of our spectro-photometric monitoring of XZ Tau. https://arxiv.org/abs/2404.09361

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