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Are x-ray detected active galactic nuclei in dwarf galaxies gamma-ray bright?

Milena Crnogorčević1,*, Tim Linden1,2,†, and Annika H. G. Peter3,4,5,‡

  • *Contact author: milena.crnogorcevic@fysik.su.se
  • †Contact author: linden@fysik.su.se
  • ‡Contact author: peter.33@osu.edu
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Phys. Rev. D 113, 123059 – Published 22 June, 2026

DOI: https://doi.org/10.1103/7dkc-t7f2

Abstract

The γ-ray emission from active galactic nuclei (AGN), including both beamed blazars and misaligned-AGN, dominates the extragalactic γ-ray point-source population count and flux. While multiwavelength studies have detected an increasing number of AGN within dwarf galaxies in the local Universe, γ-ray emission has so far only been associated with systems hosting supermassive black holes (SMBHs). Dwarf-galaxy AGN are of particular interest because their central black holes fall in the intermediate-mass black hole regime, offering insight into the early evolution of SMBHs. Using 15 years of Fermi-LAT data, we present the first search for γ-ray emission from dwarf-galaxy AGN. In the sample of 67 x-ray-selected dwarf-galaxy AGN, we find no sources that exceed the Fermi-LAT detection threshold. However, a joint-likelihood analysis reveals a modest, trials-corrected population-level excess (∼2σ) above blank-field expectations at very soft photon indices Γ≳3.8 above 500 MeV. This hint is most pronounced when source contributions are weighed by MIMBH,iα/di2, with α≃1–1.5, suggesting—but not confirming—that γ-ray emission could scale with the central black hole mass or a property correlated with it (e.g., accretion rate), but with a markedly softer spectrum than in SMBH-hosted AGN.

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Phys. Rev. D 113, 123059– Published 22 June, 2026
  • Received 13 October 2025
  • Accepted 28 May 2026
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