论文标题
磁盘进动解释LMC X-4的超轨道调制：Swift监视活动的结果
Disk precession to explain the super-orbital modulation of LMC X-4: results from the Swift monitoring campaign
论文作者
论文摘要
我们研究了高质量X射线二元系统LMC X-4的光谱变化，以了解超出其超轨道调制的起源和机制（30.4天）。为此，我们获得了Swift/XRT（0.3-10 KEV）的监视活动，并使用了长达多年的Swift/BAT调查数据（15-60 KEV）补充了这些数据。我们在最大通量时期发现了使用SWIFT/XRT和NUSTAR观察的宽带X射线频谱的自谐，身体动机的描述。我们将频谱分解为散装+热成分的总和，磁盘反射成分以及标准的Shakura-Sunyaev积聚磁盘的软贡献。我们将该模型应用于超级轨道时期的20个相选择的Swift光谱。我们发现不同成分的相位依赖性通量比，而吸收柱没有显着变化。磁盘的发射相对于硬通量是分离的。我们将其解释为几何效应，其中磁盘的内部相对于遮盖的外部区域而倾斜。
We studied the spectral changes of the high-mass X-ray binary system LMC X-4 to understand the origin and mechanisms beyond its super-orbital modulation (30.4 days). To this aim, we obtained a monitoring campaign with Swift/XRT (0.3-10 keV) and complemented these data with the years-long Swift/BAT survey data (15-60 keV). We found a self-consistent, physically motivated, description of the broadband X-ray spectrum using a Swift/XRT and a NuSTAR observation at the epoch of maximum flux. We decomposed the spectrum into the sum of a bulk+thermal Comptonization, a disk-reflection component and a soft contribution from a standard Shakura-Sunyaev accretion disk. We applied this model to 20 phase-selected Swift spectra along the super-orbital period. We found a phase-dependent flux ratio of the different components, whereas the absorption column does not significantly vary. The disk emission is decoupled with respect to the hard flux. We interpret this as a geometrical effect in which the inner parts of the disk are tilted with respect to the obscuring outer regions.
