Setting limits on blazar-boosted dark matter with xenon-based detectors

TL;DR

This work introduces blazar-boosted dark matter as a method to probe sub-GeV dark matter with xenon-based detectors by accelerating DM in blazar jets to energies that yield detectable nuclear recoils. It builds a full source-to-detector framework, including jet physics, DM density profiles near the central black hole, Earth attenuation, and detector response, and applies it to public XENON1T and LZ data from TXS 0506+056. Using three DM halo models (NFW, Gondolo-Silk spike, and a 3-zone profile) and detector-specific analyses (XENON1T open likelihood and LZ EFT), the paper derives model-dependent exclusion regions on the DM–nucleon cross section for roughly 1 MeV DM, with cross sections spanning approximately 10^-31 to 10^-28 cm^2. A central finding is that astrophysical uncertainties in the inner Galactic center dominate the limits, underscoring the need for improved halo modeling and the value of recasting direct-detection results for boosted-DM scenarios as a complement to conventional searches for light dark matter.

Abstract

Dual-phase xenon time projection chambers achieve optimal sensitivity for dark matter in the 10 to 1000 GeV/c$^2$ 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 that can leave detectable nuclear recoil signals in xenon-based detectors on Earth. We present the first blazar-boosted dark matter search that incorporates 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 through to detector response, and we explore how the host-galaxy dark matter density profile impacts the analysis. We set model-dependent exclusion regions on the dark-matter-nucleon scattering cross section for m$_χ$ approximately 1 MeV dark matter, between 5.8$\times 10^{-31}$ cm$^2$ and 6.3$\times 10^{-29}$cm$^2$ using XENON1T data, and between 9.9$\times 10^{-32}$ cm$^2$ and 2.5$\times 10^{-28}$ cm$^2$ from LZ effective field theory (EFT) dark matter searches. Our results show that astrophysical uncertainties, especially those in the dark-matter distribution near the supermassive black hole, are the main limitation of this search rather than detector effects. The limits are therefore model-dependent and should be seen as exploratory, highlighting both the potential and the present uncertainties of blazar-boosted dark matter as a probe of light dark matter.

Figures (3)

• Figure 1: Dark matter density (blue lines, left $y$-axis) and integrated column density (orange lines, right $y$-axis) as a function of distance from the galactic center for three different dark matter profiles. Dashed lines refer to the NFW DM profile model, dotted lines to GS one, and solid lines show the 3-zone model. Vertical thin lines mark the capture radius ($4R_{\text{S}}$), radius of influence ($R_{\text{infl}}$), and spike extension ($R_{\text{spike}}$), defining the boundaries between the three zones.
• Figure 2: Comparison of nuclear recoil energy spectra in liquid xenon for a 46.4 WIMP boosted by TXS 0506+056. In black is the expected energy deposition spectrum in liquid xenon, while in blue is the signal from the LZ EFT analysis that best fits the blazar-boosted energy deposition, a 1 WIMP coupling to nuclear spin ($\mathcal{O}_4$). Green lines show the efficiency for the XENON1T WIMP search reaching $\sim$50XENON:2018voc, and for the LZ EFT analysis where the energy range is extended to above $250\keV$LZ:2023lvz. The comparison illustrates how blazar-boosted dark matter can produce signals in energy ranges that extend beyond typical WIMP search windows.
• Figure 3: Constraints on the DM cross section as function of WIMP mass for blazar-boosted dark matter. The blue line shows the constraint using the XENON1T open likelihood xenon1tbinferenceXENON:2018voc, while the red lines indicate recasted limits from the LZ EFT search LZ:2023lvz. Full lines illustrate the constraint using the three-zone model DM column density, while the dashed and dotted lines show the constraints for the NFW and GS DM density model, respectively. The upper edge of the constrained region is due to the attenuation of the DM flux by the Earth. We show the same limits for different dark-matter density profiles to highlight that the choice of halo model can strongly affect the resulting constraints.