Dark Photon Limits from Patchy Dark Screening of the Cosmic Microwave Background

Area of Science:

• Cosmology
• Particle Physics
• Astrophysics

Background:

• Dark photons are hypothetical particles that interact with Standard Model photons.
• Kinetic mixing between dark photons and Standard Model photons can create observable effects in the cosmic microwave background (CMB).
• Large-scale structures can facilitate the conversion of photons to dark photons, leading to spectral anisotropies in the CMB.

Purpose of the Study:

• To constrain the kinetic mixing parameter (ϵ) of dark photons.
• To probe dark photon properties within a specific mass range (10⁻¹³ eV to 10⁻¹¹ eV).
• To improve upon existing limits for dark photon interactions.

Main Methods:

• Utilizing predictions for patchy dark screening signals in the CMB.
• Applying advanced component separation techniques.
• Cross-correlating data from the Planck CMB satellite and the unWISE galaxy survey.

Main Results:

• Achieved the tightest constraints to date on the dark photon kinetic mixing parameter, ϵ ≲ 4.5 × 10⁻⁸ (95% confidence level).
• Established limits nearly an order of magnitude stronger than previous studies.
• Constrained dark photon masses in the range of 10⁻¹³ eV to 10⁻¹¹ eV.

Conclusions:

• The study provides significant new limits on dark photon properties, impacting theories of dark matter and fundamental physics.
• The applied methods demonstrate a powerful approach for searching for new physics in cosmological data.
• This research opens avenues for future investigations into dark photon interactions and their cosmological implications.