Setting Limits on Blazar-Boosted Dark Matter with Xenon-based Detectors

Abstract: Dual-phase xenon time projection chambers achieve optimal sensitivity for dark matter in the $10$--$1000~\mathrm{GeV}/c<sup>2$ mass range, but sub-GeV dark matter particles lack sufficient energy to produce nuclear recoils above detection thresholds in these detectors. Blazar-boosted dark matter offers a way to overcome this limitation: relativistic jets in active galactic nuclei can accelerate light dark matter in their host-galaxy halos to energies capable of producing detectable nuclear recoil signals in xenon-based detectors on Earth. We present the first blazar-boosted dark matter search incorporating detector response modeling, using public data from XENON1T and LZ for the blazar TXS~0506+056. We model dark matter--proton scattering in the jet environment, covering the full process from jet acceleration to detector response. We explore how the host-galaxy dark matter density profile impacts our analysis. Using XENON1T data, we exclude dark matter--nucleon cross sections for $m_\chi \sim 1~\mathrm{MeV}$ in the range $$5.8\times 10^{{-31}~\mathrm{cm^2}} \lesssim \sigma_{\chi n} \lesssim 6.3\times 10<sup>{-29}~\mathrm{cm<sup>2}$$, and using LZ EFT searches we constrain $$9.9\times 10^{{-32}~\mathrm{cm^2}} \lesssim \sigma_{\chi n} \lesssim 2.5\times 10<sup>{-28}~\mathrm{cm<sup>2}$$. Our results show that astrophysical uncertainties, especially the dark matter density profile near the supermassive black hole, set the primary limitation on the sensitivity rather than detector systematics. These findings highlight blazar-boosted dark matter as a promising probe of light dark matter and motivate further astrophysical modeling.