Timing and Single-pulse Study of Pulsar J1909+0122 Discovered by CRAFTS

作者：Chen, Yutong; Wang, Pei^*; Li, Di; Guegercinoglu, Erbil; Zhao, Rushuang; Meng, Lingqi; Yuan, Jianping; Niu, Jiarui; Zhu, Weiwei; Feng, Yi; Miao, Chenchen; Niu, Chenhui; Wu, Qingdong; Wang, Na; Wang, Shen; Xie, Xiaoyao; Xue, Mengyao; Yao, Jumei; Yuan, Mao; You, Shanping; Yu, Xuhong; Yue, Youling; Zhang, Jie; Zhang, Junshuo; Zhang, Lei; Wang, Yabiao; Gan, Zhenye; Li, Yuxi; Sun, Zhongyi; Wang, Chengjie

来源：Research in Astronomy and Astrophysics, 2023, 23(8): 085022.

DOI：10.1088/1674-4527/acd89d

• (stars:) pulsars: general
• (stars:) pulsars: individual (PSR J1909+0122)
• stars: neutron

report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope (FAST) as part of the Commensal Radio Astronomy FAST Survey. PSR J1909+0122 has a spin period of 1.257 s and a dispersion measure of 186.2 pc cm-3. The averaged pulse profile shows two distinct components. We performed a single-pulse study based on a one-hour observation at 1.25 GHz on 2021 August 23. We used a threshold of 5sep to measure the nulling fraction (NF) as 63% +/- 1.5%. The longitude-resolved fluctuation spectra and fast Fourier transform spectra of the binary sequences revealed the quasi-periodicity of nulling with a period of 30 rotation periods. We examined the reliability of the periodicity by comparing it to random noise injection. The NF,. E, and modulation periodicity PM of PSR J1909+0122 were compared with other periodic nulling pulsars, showing that the source of J1909+0122 has the second largest NF in the population. Long-term timing observations over six months were used to derive the phase-connected ephemeris of this pulsar. The measured P and. P values disfavor dipolar geometry for polar gap models, and the prediction for a space-charge-limited flow model in the case of inverse Compton scattering is only just above the death line. In this work, PSR J1909+0122 has revealed possible correlations between nulling behavior and pulsar properties, which will help to shed light on the pulsar emission mechanism and its temporal evolution in future observations.

• 单位
  中国科学院研究生院; 复旦大学