Direct Detection of Dark Photon Dark Matter Using Radio Telescopes.

Area of Science:

• Astrophysics
• Particle Physics
• Cosmology

Background:

• Dark matter constitutes a significant portion of the universe's mass.
• Ultralight dark photons are a compelling dark matter candidate.
• Kinetic mixing describes the interaction between dark photons and Standard Model particles.

Purpose of the Study:

• To propose and evaluate a novel method for detecting ultralight dark photon dark matter (DPDM).
• To leverage radio telescope technology for direct DPDM detection.
• To establish experimental constraints on the kinetic mixing parameter.

Main Methods:

• Utilizing radio telescopes to detect monochromatic radio signals generated by DPDM.
• Analyzing observational data from the FAST telescope.
• Proposing future searches with large-scale interferometric arrays like LOFAR and SKA1.

Main Results:

• The FAST telescope observation data yielded an upper limit on the kinetic mixing parameter of 10^{-12} for DPDM oscillation frequencies between 1-1.5 GHz.
• This constraint is approximately one order of magnitude stronger than existing cosmic microwave background constraints.
• LOFAR and SKA1 are projected to achieve significant sensitivity improvements across a broad frequency range (10 MHz to 10 GHz).

Conclusions:

• Radio telescopes offer a powerful tool for the direct detection of ultralight dark photon dark matter.
• Current observations with FAST have already provided competitive constraints on DPDM properties.
• Future advancements with next-generation radio arrays promise to substantially enhance our ability to probe DPDM models.