论文标题
Astrosat观察毫秒X射线Pulsar SAX J1808.4-3658在其2019年爆发期间
The AstroSat observation of accreting millisecond X-ray pulsar SAX J1808.4-3658 during its 2019 outburst
论文作者
论文摘要
我们报告了对毫秒X射线脉冲脉冲SAX J1808.4-3658的Astrosat数据集的分析，该数据集在其2019年爆发期间获得。我们发现$ \ sim 401 $ Hz的相干脉动和与先前研究一致的轨道溶液。 3-20 KEV Pulse配置文件可以很好地配合三个和谐相关的正弦曲线成分，其背景校正的分数幅度为$ \ sim 3.5 \％$，$ \ sim 1.2 \％$和$ \ sim 0.37 \％0.37 \％$，分别用于基本，第二和第三次谐波。我们的能量分辨脉冲曲线进化研究表明了强大的能量依赖性。我们还观察到谐波期间的基本和硬滞后滞后滞后。 SAX J1808.4-3658的宽带光谱可以很好地描述，将热发射组件与$ kt \ sim 1 $ keV结合在一起，这是一种来自热的Corona和FE引起的宽发射线的热综合（$γ\ sim 1.67 $）。
We report on the analysis of the AstroSat dataset of the accreting millisecond X-ray pulsar SAX J1808.4-3658, obtained during its 2019 outburst. We found coherent pulsations at $\sim 401$ Hz and an orbital solution consistent with previous studies. The 3-20 keV pulse profile can be well fitted with three harmonically related sinusoidal components with background-corrected fractional amplitude of $\sim 3.5 \%$, $\sim 1.2 \%$ and $\sim 0.37 \%$ for fundamental, second and third harmonic, respectively. Our energy-resolved pulse profile evolution study indicate a strong energy dependence. We also observed a soft lag in fundamental and hard lag during its harmonic. The broadband spectrum of SAX J1808.4-3658 can be well described with a combination of thermal emission component with $kT \sim 1$ keV, a thermal Comptonization ($Γ\sim 1.67$) from the hot corona and broad emission lines due to Fe.
