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arXiv · 2609.28719

A comprehensive multi-wavelength study of two X-ray emitting Be stars

Hema Anilkumar·Blesson Mathew·Savithri H. Ezhikode·Sreeja S. Kartha·Suman Bhattacharyya·Sneha Nedhath·Ajith N
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Abstract

We present a multi-wavelength study of two X-ray-emitting Be stars, CXOU J052218.4+332820 (Star 1) and CXOU J052304.2+332846 (Star 2), identified from the LAMOST DR5 Hot emission-line stars catalog. Our spectroscopic and photometric analyses indicate that Star 1 is a main-sequence B5e star, whereas Star 2 is a pre-main-sequence B7e star. The LAMOST spectrum of Star 1 exhibits shell-type Feii, Paschen, and Oi emission from circumstellar regions extending to ~ 3 - 5Rstar. TESS period analysis reveals a rapid rotational period of ~ 0.355 d and an inclination angle of ~ 68 deg, confirming the Classical Be nature of Star 1. In contrast, Star 2 shows strong accretion signatures, including inverse P-Cygni Feii and redshifted Hei absorption features. Its ZTF light curves display irregular dimming events of up to ~ 3 mag and quasi-periodic variability on timescales of ~ 50 - 110 d, consistent with circumstellar obscuration in an accreting Herbig Be star. To further investigate the high-energy properties of the two systems, we analyzed their Chandra X-ray spectra. Chandra spectroscopy yields moderate plasma temperatures (kT ~ 1.7-1.8 keV) and X-ray luminosities of logL_X ~ 30.4-30.6 erg/s, comparable to those observed in magnetically active coronae. Furthermore, the positional agreement between the Chandra and Gaia coordinates indicates that the X-ray emission is spatially associated with the optical systems rather than a nearby resolved companion. These results suggest that the observed X-ray emission originates from magnetically influenced circumstellar activity, consistent with magnetically confined wind-shock (MCWS) or magnetically torqued disk scenarios.

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Hema Anilkumar, Blesson Mathew, Savithri H. Ezhikode, Sreeja S. Kartha, Suman Bhattacharyya, Sneha Nedhath, Ajith N. 2026-09-23. A comprehensive multi-wavelength study of two X-ray emitting Be stars. https://arxiv.org/abs/2609.28719

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