超新星遗迹和脉冲星风云的X射线偏振成像  

X-ray Polarization Imaging of Supernova Remnants and Pulsar Wind Nebulae

作　　者：罗天贤 周平 LUO Tian-xian;ZHOU Ping(School of Astronomy and Space Science,Nanjing University,Nanjing 210046,China;Key Laboratory of Modern Astronomy and Astrophysics,Ministry of Education,Nanjing 210046,China)

机构地区：[1]南京大学天文与空间科学学院,南京210046 [2]现代天文与天体物理教育部重点实验室,南京210046

出　　处：《天文学进展》2024年第1期76-85,共10页Progress In Astronomy

基　　金：国家自然科学基金(12273010)。

摘　　要：年轻超新星遗迹和脉冲星风云中的高能粒子可以通过同步辐射产生X射线。对该辐射的偏振测量有助于揭示粒子加速区磁场的性质,进而研究粒子加速的机制。首颗X射线偏振成像卫星于2021年底发射升空,已揭示了数个年轻超新星遗迹和脉冲星风云的X射线偏振图像。观测显示,仙后A和第谷超新星遗迹的偏振度较低,平均值分别约为2.5%和9%;而蟹状星云和船帆脉冲星风云的偏振度较高,平均值分别约为20%和45%。结果表明脉冲星风云的磁场较为有序,而两个年轻超新星遗迹的粒子加速区磁场是高度湍动的,且激波附近的磁场结构呈现径向分布。未来,随着对IXPE的使用越来越广泛,以及与我国建设中的增强型X射线时变与偏振探测器(eXTP)等更多望远镜投入使用,以上两类天体的磁场构型和粒子加速模型将得到进一步的限定。High energy particles near the particle acceleration region in young supernova remnants and pulsar wind nebulae can emit X-ray synchrotron radiation.The polarization measurement of this radiation can reveal the properties of the magnetic eld in the particle acceleration region,and further study the mechanism of particle acceleration.As the rst X-ray polarization imaging satellite,the Imaging X-ray Polarization Detector(IXPE)was launched in late 2021 and revealed the X-ray polarization images of several young supernova remnants and pulsar wind nebulae.Observations show that Cas A and Tycho's supernova remnant have low polarization degrees with average values of about 2.5%and 9%,respec-tively,while the Crab Nebula and Vela pulsar wind nebula have higher polarization degrees,averaging about 20%and 45%,respectively.The results indicate that the magnetic eld of the pulsar wind nebulae is relatively ordered,while the magnetic eld of the particle accel-eration region in the two young supernova remnants is highly turbulent and the magnetic eld structure near the shock wave shows a radial distribution.In the future,with more extensive observations of IXPE and more telescopes such as the enhanced X-ray Timing and Polarimetry(eXTP)mission planned by China in use,the magnetic eld con guration and particle acceleration models of the above two types of objects will be further constrained.

关 键 词：超新星遗迹 脉冲星风云 偏振 X射线天文学 粒子加速 

分 类 号：P145.3[天文地球—天体物理]