In Situ Measurements of Dark Photon Dark Matter Using Parker Solar Probe: Going beyond the Radio Window

TL;DR

This paper uses in-situ measurements from the Parker Solar Probe to search for dark photon dark matter signatures in a frequency range inaccessible to Earth-based radio telescopes, setting new constraints on the kinetic mixing parameter.

Contribution

It demonstrates the first use of PSP data to probe dark photon dark matter in the 70 kHz to 20 MHz range, surpassing previous cosmic microwave background limits.

Findings

Established the most stringent constraints on $\\epsilon$ for 70 kHz to 20 MHz.

PSP data provided stronger constraints than STEREO satellite data.

Surpassed early-universe cosmic microwave background limits.

Abstract

Dark photon dark matter (DPDM) emerges as a compelling candidate for ultralight bosonic dark matter, detectable through resonant conversion into photons within a plasma environment. This study employs in-situ measurements from the Parker Solar Probe (PSP), the first spacecraft to venture into the solar corona, to probe for DPDM signatures. The PSP in-situ measurements go beyond the traditional radio window, spanning frequencies between about 10 kHz and 20 MHz, a challenging range inaccessible to Earth-based radio astronomy. Additionally, the proximity of PSP to the resonant conversion location enhances the signal flux, providing a distinct advantage over ground-based observations. As a result, the PSP data establishes the most stringent constraints on the kinetic mixing parameter $\epsilon$ for DPDM frequencies between 70 kHz and 20 MHz, with values of $\epsilon \lesssim 10^{-14}-10^{-13}$. Investigating the data from STEREO satellites resulted in weaker constraints compared to those obtained from PSP. By utilizing state-of-the-art solar observations from space, we have surpassed the cosmic microwave background limits derived from early-universe observations.