Discovery of Rapid Polarization Angle Variation During the 2022 Outburst of XTE J1701-462
| Autor: | Zhao, QingChang, Li, Hong, Tao, Lian, Feng, Hua |
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| Rok vydání: | 2024 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| Popis: | The geometry of the Comptonization corona in neutron star low-mass X-ray binaries is still unclear. We conducted time-resolved polarimetric analysis of the archival observations of XTE J1701--462 obtained with the \textit{Imaging X-ray Polarimeter Explorer} during its 2022 outburst, and found that the polarization angle (PA) varied significantly with time when the source was in the normal branch (NB), with $67 \pm 8^{\circ}$ in the first epoch, $-34 \pm 8^{\circ}$ in the second, and $-58 \pm 8^{\circ}$ in the third, last epoch. Meanwhile, the polarization degree remained constant at around 2\%, above the minimum detectable polarization at the 99\% confidence level (MDP$_{99}$). The rapid PA variation causes depolarization in the time-averaged data, resulting in a nondetection as reported in the literature. The rapid (intra-day) PA variation may suggest that there is a fast transformation of the corona geometry, likely switching from a slab geometry to a more vertically extended spreading layer geometry, along with enhanced disk emission and reflection. Comment: Submitted to the Astrophysical Journal |
| Databáze: | arXiv |
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