The Astrophysical Journal (Jan 2023)
X-Ray Polarimetry of the Accreting Pulsar 1A 0535+262 in the Supercritical State with PolarLight
- Xiangyun Long,
- Hua Feng,
- Hong Li,
- Ling-Da Kong,
- Jeremy Heyl,
- Long Ji,
- Lian Tao,
- Fabio Muleri,
- Qiong Wu,
- Jiahuan Zhu,
- Jiahui Huang,
- Massimo Minuti,
- Weichun Jiang,
- Saverio Citraro,
- Hikmat Nasimi,
- Jiandong Yu,
- Ge Jin,
- Ming Zeng,
- Peng An,
- Luca Baldini,
- Ronaldo Bellazzini,
- Alessandro Brez,
- Luca Latronico,
- Carmelo Sgrò,
- Gloria Spandre,
- Michele Pinchera,
- Paolo Soffitta,
- Enrico Costa
Affiliations
- Xiangyun Long
- ORCiD
- Department of Engineering Physics, Tsinghua University , Beijing 100084, People's Republic of China
- Hua Feng
- ORCiD
- Department of Astronomy, Tsinghua University , Beijing 100084, People's Republic of China ; [email protected]
- Hong Li
- Department of Astronomy, Tsinghua University , Beijing 100084, People's Republic of China ; [email protected]
- Ling-Da Kong
- ORCiD
- Institut für Astronomie und Astrophysik , Kepler Center for Astro and Particle Physics, Eberhard Karls, Universität, Sand 1, D-72076 Tübingen, Germany
- Jeremy Heyl
- Department of Physics and Astronomy, University of British Columbia , Vancouver, BC V6T 1Z1, Canada
- Long Ji
- School of Physics and Astronomy, Sun Yat-Sen University , Zhuhai 519082, People's Republic of China
- Lian Tao
- Key Laboratory for Particle Astrophysics, Institute of High Energy Physics , Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Fabio Muleri
- ORCiD
- IAPS/INAF , Via Fosso del Cavaliere 100, I-00133 Rome, Italy
- Qiong Wu
- Department of Engineering Physics, Tsinghua University , Beijing 100084, People's Republic of China
- Jiahuan Zhu
- ORCiD
- Department of Astronomy, Tsinghua University , Beijing 100084, People's Republic of China ; [email protected]
- Jiahui Huang
- ORCiD
- Department of Engineering Physics, Tsinghua University , Beijing 100084, People's Republic of China
- Massimo Minuti
- INFN–Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
- Weichun Jiang
- Key Laboratory for Particle Astrophysics, Institute of High Energy Physics , Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Saverio Citraro
- INFN–Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
- Hikmat Nasimi
- INFN–Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
- Jiandong Yu
- School of Electronic and Information Engineering, Ningbo University of Technology , Ningbo, Zhejiang 315211, People's Republic of China
- Ge Jin
- North Night Vision Technology Co., Ltd. , Nanjing 211106, People's Republic of China
- Ming Zeng
- Department of Engineering Physics, Tsinghua University , Beijing 100084, People's Republic of China
- Peng An
- School of Electronic and Information Engineering, Ningbo University of Technology , Ningbo, Zhejiang 315211, People's Republic of China
- Luca Baldini
- ORCiD
- INFN–Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
- Ronaldo Bellazzini
- ORCiD
- INFN–Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
- Alessandro Brez
- INFN–Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
- Luca Latronico
- ORCiD
- INFN, Sezione di Torino , Via Pietro Giuria 1, I-10125 Torino, Italy
- Carmelo Sgrò
- ORCiD
- INFN–Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
- Gloria Spandre
- INFN–Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
- Michele Pinchera
- INFN–Pisa, Largo B. Pontecorvo 3, I-56127 Pisa, Italy
- Paolo Soffitta
- ORCiD
- IAPS/INAF , Via Fosso del Cavaliere 100, I-00133 Rome, Italy
- Enrico Costa
- ORCiD
- IAPS/INAF , Via Fosso del Cavaliere 100, I-00133 Rome, Italy
- DOI
- https://doi.org/10.3847/1538-4357/acd0af
- Journal volume & issue
-
Vol. 950,
no. 2
p. 76
Abstract
The X-ray pulsar 1A 0535+262 exhibited a giant outburst in 2020, offering us a unique opportunity for X-ray polarimetry of an accreting pulsar in the supercritical state. Measurement with PolarLight yielded a nondetection in 3–8 keV; the 99% upper limit of the polarization fraction (PF) is found to be 0.34 averaged over spin phases, or 0.51 based on the rotating vector model. No useful constraint can be placed with phase-resolved polarimetry. These upper limits are lower than a previous theoretical prediction of 0.6–0.8, but consistent with those found in other accreting pulsars, like Her X-1, Cen X-3, 4U 1626−67, and GRO J1008−57, which were in the subcritical state, or at least not confidently in the supercritical state, during the polarization measurements. Our results suggest that the relatively low PF seen in accreting pulsars cannot be attributed to the source not being in the supercritical state, but could be a general feature.
Keywords
