低质量X射线双星系统中的辐射涵盖射电到X射线波段（甚至到伽马射线波段）。X射线辐射通常认为是来自吸积盘内区，射电辐射主要由喷流贡献，而紫外、光学以及近红外（UV/OPT/NIR）辐射可能由多种辐射机制贡献。确定X射线双星系统中UV/OPT/NIR辐射的主导机制研究仍在进行中。研究X射线双星爆发过程中不同波段辐射流量之间的相关性是一种重要的研究方法，它可以为我们理解吸积过程提供重要的研究信息。 我们总结了不同源中存在的幂律相关性的观测结果；介绍了用于解释UV/OPT/NIR辐射起源的若干理论模型；并对UV/OPT/NIR辐射起源研究提出来了展望。 我们利用SWIFT卫星分析了黑洞-低质量X射线双星 SWIFT J1753.5-0127 在其长达12年的爆发期间的同时性光学、紫外和X射线数据。我们发现，在爆发的硬态期间，紫外、光学和X射线辐射流量具有很强的相关性。我们使用幂律函数（Fuv/opt ∝ Fxβ）拟合数据，发现当光学到紫外波长从~ 5402 Å 减小到~ 2030 Å 时，幂律指数β 从~ 0.24增加到~ 0.33。我们探究了可能的物理机制，并认为在爆发过程中，紫外、光学辐射主要由外吸积盘的黏滞加热过程主导。 我们还发现，出现在X射线波段中的低强度峰偏离了硬态相关性，并认为吸积盘内区的软X射线辐射成分的增加是相关性偏离的主要原因。
其他摘要
Emission from low-mass X-ray binaries (LMXBs) covers a broad range of energies from radio to X-rays, even to γ-rays. X-ray emission is typically thought to radiate from the inner region of an accretion flow, and the radio emission is predominantly contributed by a jet. Radiation observed in the ultraviolet (UV), optical (OPT) and near-infrared (NIR) bands may, however, involve a variety of emitting mechanisms. Pinning down the dominant mechanism of UV/OPT/NIR radiation is still a work in progress. Studying the correlations between emissions at different energies during the outbursts in X-ray binaries is an important research method, which can provide us valuable information for our understanding of the accretion processes.We review the power-law correlation study in several X-ray binary sources, and summarize the most probable theoretical models in explaining the origin of the UV/OPT/NIR emission, and give an outlook on the studying the origin of UV/OPT/NIR emission. We analyse the simultaneous OPT, UV and X-ray data of the BH-LMXB SWIFT J1753.5-0127 during its ~ 12-year long outburst with the Neil Gehrels Swift Observatory. We find that the UV/OPT and X-ray emission are strongly correlated during the hard states of the outburst. We fit the relation with a power-law function Fuv/opt ∝ Fxβ and find that the power-law index β increases from ~ 0.24 to ~ 0.33 as the UV/optical wavelength decreases from ~ 5402 Å to ~ 2030 Å . We explore the possible reasons for this and suggest that in SWIFT J1753.5-0127 the UV/optical emission is dominated by a viscously heated accretion disc at large radii. We find that the data that deviate from the correlation correspond to the low-intensity peaks appeared in the X-ray band during the outburst, and suggest that these deviations are driven by the emission from the inner part of the accretion disc.
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