Timing Properties of the X-Ray Accreting Pulsar 1A 0535+262 Studied with Insight-HXMT
Abstract
We report results on the timing analysis of the 2020 giant outburst of 1A 0535+262, using broadband data from Insight-HXMT. The analysis of the pulse profile evolution from the subcritical-luminosity to the supercritical-luminosity regime is presented for the first time. We found that the observed pulse profile exhibits a complex dependence on both energy and luminosity. A dip structure at the energy of the cyclotron resonant scattering features is found for the first time in the pulse fraction-energy relation of 1A 0535+262, when the outburst evolves in a luminosity range from 4.8 × 1037 to 1.0 × 1038 erg s-1. The observed structure is luminosity dependent and appears around the source critical luminosity (~6.7 × 1037 erg s-1).
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 2022
- DOI:
- 10.3847/1538-4357/ac8230
- arXiv:
- arXiv:2208.13340
- Bibcode:
- 2022ApJ...935..125W
- Keywords:
-
- X-ray binary stars;
- Pulsars;
- X-ray astronomy;
- 1811;
- 1306;
- 1810;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- doi:10.3847/1538-4357/ac8230