论文标题
如成像X射线极化探索器所观察到的平均通量状态下MRK〜421的X射线极化视图
The X-ray Polarization View of Mrk~421 in an Average Flux State as Observed by the Imaging X-ray Polarimetry Explorer
论文作者
论文摘要
超级质量黑洞喷气机中的粒子加速机制，例如冲击加速度，磁重新连接和湍流，在Blazars的多波长极化特性中有可观察到的特征。成像X射线极化探索器（IXPE）的最新发射使我们首次使用X射线频带（2-8 KEV）中的极化来探测高频蛋白质蛋白质蛋白质同时发射的性能。我们报告了X射线线性极化的发现（度$π_ {\ rm x} = 15 \ pm $ 2 \％和电动矢量位置角度$ψ_ {\ rm x} = 35^\ circ \ circ \ pm4^\ circ $）来自HSP MRK 〜421的射击，平均x-rux x-ray play play flay flay hsp mrk〜421。同时，发现光学，红外和毫米波长的极化程度至少降低3倍。在IXPE指向期间，源的X射线通量增加了2.2倍，而极化行为却一致，没有可变性。与更长的波长相比，$π_ {\ rm x} $的较高水平，并且没有明显的极化可变性，这表明在观察过程中，MRK 421射流中最有可能的X射线发射位点是X射线发射位点。多波长极化特性与能量分层的电子种群一致，在该电子种群中，在较长波长下发射的颗粒距离加速度位置较远，在那里它们经历了更无序的磁场。
Particle acceleration mechanisms in supermassive black hole jets, such as shock acceleration, magnetic reconnection, and turbulence, are expected to have observable signatures in the multi-wavelength polarization properties of blazars. The recent launch of the Imaging X-ray Polarimetry Explorer (IXPE) enables us, for the first time, to use polarization in the X-ray band (2-8 keV) to probe the properties of the jet synchrotron emission in high-frequency-peaked BL Lac objects (HSPs). We report the discovery of X-ray linear polarization (degree $Π_{\rm x}=15\pm$2\% and electric-vector position angle $Ψ_{\rm x}=35^\circ\pm4^\circ$) from the jet of the HSP Mrk~421 in an average X-ray flux state. At the same time, the degree of polarization at optical, infrared, and millimeter wavelengths was found to be lower by at least a factor of 3. During the IXPE pointing, the X-ray flux of the source increased by a factor of 2.2, while the polarization behavior was consistent with no variability. The higher level of $Π_{\rm x}$ compared to longer wavelengths, and the absence of significant polarization variability, suggest a shock as the most likely X-ray emission site in the jet of Mrk 421 during the observation. The multiwavelength polarization properties are consistent with an energy-stratified electron population, where the particles emitting at longer wavelengths are located farther from the acceleration site, where they experience a more disordered magnetic field.
