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arXiv · 2502.03830

Unveiling the emission properties of three long-period pulsars using FAST

Abstract

We detail the emission behaviors of three long-period pulsars detected using the Five-hundred-meter Aperture Spherical radio Telescope (FAST) during the CRAFTS survey. Their rotational periods range from 1.83 s to 4.75 s, and the null fractions measure between 28% and 53%. PSR J1945+1211 and PSR J2323+1214 exhibited quasi-periodic nulls, with duration of around 57 seconds. The longest null was observed in PSR J1945+1211, lasting 76 seconds. PSR J2323+1214 displayed varying null fractions between its leading and trailing components. For the first time in PSR J2323+1214, we detected five dwarf pulses, which are much weaker and narrower pulses than typical burst pulses. In addition, we investigate the microstructure of PSR J1900-0134 for the first time, revealing intricate pulses of up to 2.05 milliseconds and noting its complex emission characteristics. Bright pulses occur in all of these sources at different rates. These observations suggest complex magnetospheric processes, potentially related to magnetic reconnections, and provide insights into the origins of bright and microstructure pulses, as well as their distinctions from ordinary pulses.

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H. M. Tedila, D. Li, P. Wang, R. Yuen, J. P. Yuan, N. Wang, Z. G. Wen, S. J. Dang, A. G. Tegegne, R. Rejep, C. C. Miao, FAST Collaboration. 2025-02-06. Unveiling the emission properties of three long-period pulsars using FAST. https://doi.org/10.3847/1538-4365%2Fadb280

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