AI 中文总结
本研究通过5.5年多历元光谱与测光分析，结合Gaia、TESS等数据，证实HD 249179为兼具混合脉动的经典Be星，无强证据支持其为大质量X射线双星。
AI 中文摘要
HD 249179是一颗B5型恒星，其分类尚不明确，既可能是经典Be星，也可能是大质量X射线双星（HMXB）系统；本研究对其开展了2017-2023年共5.5年的首次多历元光谱与测光分析。来自LAMOST、BeSS和喜马拉雅Chandra望远镜的光学光谱显示，H-alpha在6天内出现-17.6至-3.2埃的大幅变化，2022年又回升至-31.3埃，且存在帕邢线和O I线，证实其星周盘动力学活跃；H-alpha双峰轮廓呈现0.92-1.28的弱V/R比变化，表明存在单臂密度波。TESS观测显示其兼具beta Cephei型与慢脉动B型的混合脉动，主频率为3.5 c/d和1.5-1.6 c/d，还出现类爆发增亮及相位相关的频率演化；光学亮度与H-alpha等值宽度呈同步反相关，表明星盘倾角适中。Gaia DR3的CMD分析排除了HD 249179为BeXRB的可能，将其归入经典Be星区域；BeppoSAX巡天虽曾被X射线编目，但未探测到超过灵敏度极限的辐射。本分析表明，HD 249179极可能是一颗具有可变星周盘活动和混合脉动的经典Be星，无强证据支持其HMXB分类。
英文摘要
HD 249179, a B5 star with unclear classification as either a classical Be star or a high-mass X-ray binary (HMXB) system, is investigated using the first multi-epoch spectral and photometric analysis over 5.5 years (2017-2023). Optical spectroscopy from LAMOST, BeSS, and the Himalayan Chandra Telescope show large H-alpha variability (-17.6 to -3.2 angstrom, in six days, returning to -31.3 angstrom, in 2022) and the presence of Paschen and O I lines, confirming active circumstellar disc dynamics. H-alpha double peak profiles show weak V/R ratio variations 0.92--1.28 indicating one-armed density waves. TESS observations presents hybrid beta Cephei/slowly pulsating B-type variability with primary frequencies of 3.5 c/d and 1.5-1.6 c/d, and an outburst-like brightening with phase-dependent frequency evolution. Simultaneous anti-correlation between optical brightness and H$α$ equivalent width suggest moderate disc inclination. Gaia DR3 CMD analysis rules out HD 249179 as a BeXRB but instead places it in the classical Be-star region. The BeppoSAX survey, despite previous X-ray cataloging, found no emission above the sensitivity limits. Our analysis shows that HD 249179 is most likely a classical Be star with variable circumstellar disc activity and hybrid pulsations, and that there is no strong evidence for an HMXB classification.
CommentsAccepted in Research in Astronomy and Astrophysics, 28 pages, 12 figures
