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arXiv · 2509.03001

Low-frequency observations of low-mass binary systems with neutron star candidates

Elena Brylyakova·Marina Afonina·Gayane Tyul'basheva·Sergei B. Popov·Sergei Tyul'bashev
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Abstract

Recently, astrometric and spectroscopic observations resulted in the discovery of several low-mass binaries with invisible components, which are expected to be compact objects. In about two dozen cases, the masses of these components are consistent with neutron stars. We use low-frequency archival data obtained with the Large Phased Array in Pushchino to search for radio emission from five of these systems. For all the systems, we do not detect persistent or periodic emission. In one case (2MASS J1527+3536), we identify a single radio burst with a flux of 13 Jy and a duration of 0.13 s. However, the dispersion measure of the burst does not correspond to an expected value for the source. We discuss several possibilities to explain the properties of this burst.

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Elena Brylyakova, Marina Afonina, Gayane Tyul'basheva, Sergei B. Popov, Sergei Tyul'bashev. 2025-09-03. Low-frequency observations of low-mass binary systems with neutron star candidates. https://arxiv.org/abs/2509.03001

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