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arXiv · 2004.00011

Green Bank and Effelsberg Radio Telescope Searches for Axion Dark Matter Conversion in Neutron Star Magnetospheres

Joshua W. Foster·Yonatan Kahn·Oscar Macias·Zhiquan Sun·Ralph P. Eatough·Vladislav I. Kondratiev·Wendy M. Peters·Christoph Weniger·Benjamin R. Safdi
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Abstract

Axion dark matter (DM) may convert to radio-frequency electromagnetic radiation in the strong magnetic fields around neutron stars. The radio signature of such a process would be an ultra-narrow spectral peak at a frequency determined by the mass of the axion particle. We analyze data we collected from the Robert C. Byrd Green Bank Telescope in the L-band and the Effelsberg 100-m Telescope in the L-Band and S-band from a number of sources expected to produce bright signals of axion-photon conversion, including the Galactic Center of the Milky Way and the nearby isolated neutron stars RX J0720.4-3125 and RX J0806.4-4123. We find no evidence for axion DM and are able to set some of the strongest constraints to-date on the existence of axion DM in the highly-motivated mass range between ~5-11 $\mu$eV.

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Joshua W. Foster, Yonatan Kahn, Oscar Macias, Zhiquan Sun, Ralph P. Eatough, Vladislav I. Kondratiev, Wendy M. Peters, Christoph Weniger, Benjamin R. Safdi. 2020-03-31. Green Bank and Effelsberg Radio Telescope Searches for Axion Dark Matter Conversion in Neutron Star Magnetospheres. https://doi.org/10.1103/physrevlett.125.171301

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