Search for MeV-Scale Axionlike Particles and Dark Photons with PandaX-4T

Area of Science:

• Particle Physics
• Cosmology
• Astrophysics

Background:

• Axionlike particles (ALPs) and dark photons (DPs) are leading candidates for dark matter.
• Direct detection experiments are crucial for probing these candidates.
• The PandaX-4T detector offers a sensitive platform for dark matter searches.

Purpose of the Study:

• To search for signals of ALPs and DPs in the PandaX-4T liquid xenon detector.
• To establish exclusion limits on the masses of ALPs and DPs.
• To improve upon existing constraints in specific mass ranges.

Main Methods:

• Utilized 440 kg·yr of data from the PandaX-4T detector.
• Employed a binned likelihood fit to detect mono-energetic peaks from ALP/DP absorption by xenon electrons.
• Incorporated a temporal decay model for xenon isotopes to constrain background events.

Main Results:

• No significant signal excess above expected background levels was observed.
• Established the most stringent exclusion limits for ALP/DP masses between 150 keV/c² and 1 MeV/c².
• Achieved an average improvement factor of 3.5 in exclusion limits for masses between 150-400 keV/c².

Conclusions:

• The PandaX-4T experiment has placed the most stringent constraints to date on certain ALP and DP models.
• The results significantly narrow down the parameter space for these dark matter candidates.
• Future analyses can build upon these methods to further probe dark matter properties.