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arXiv · 2503.05237

Radio pulse search from Aql X-1

Long Peng·Zhaosheng Li·Yuanyue Pan·Shanshan Weng·Wengming Yan·Na Wang·Bojun Wang·Shuangqiang Wang
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Abstract

We present 12 observations of the accreting millisecond X-ray pulsar Aql X-1, taken from August 2022 to October 2023 using the Five-hundred-meter Aperture Spherical Radio Telescope at 1250 MHz. These observations covered both the quiescence and X-ray outburst states, as determined by analyzing the X-ray data from the Neutron Star Interior Composition Explorer and the Monitor of All-sky X-ray Image. Periodicity and single-pulse searches were conducted for each observation, but no pulsed signals were detected. The obtained upper limit flux densities are in the range of 2.86-5.73 uJy, which provide the lowest limits to date. We discuss several mechanisms that may prevent detection, suggesting that Aql X-1 may be in the radio-ejection state during quiescence, where the radio pulsed emissions are absorbed by the matter surrounding the system.

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Long Peng, Zhaosheng Li, Yuanyue Pan, Shanshan Weng, Wengming Yan, Na Wang, Bojun Wang, Shuangqiang Wang. 2025-03-07. Radio pulse search from Aql X-1. https://doi.org/10.3847/1538-4357%2Fadbd43

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