2026-04-22T14:28:55Zivo://CDS.VizieR/J/MNRAS/516/27362025-11-03T00:00:00ZJ.MNRASIVOAOptical variability of ~700 low mass AGNsWe present a sample of 706, z < 1.5 active galactic nuclei (AGNs) selected from optical photometric variability in three of the Dark Energy Survey (DES) deep fields (E2, C3, and X3) over an area of 4.64 deg^2^. We construct light curves using difference imaging aperture photometry for resolved sources and non- difference imaging PSF photometry for unresolved sources, respectively, and characterize the variability significance. Our DES light curves have a mean cadence of 7 d, a 6-yr baseline, and a single-epoch imaging depth of up to g ~ 24.5. Using spectral energy distribution (SED) fitting, we find 26 out of total 706 variable galaxies are consistent with dwarf galaxies with a reliable stellar mass estimate (M* < 10^9.5^M_{Sun}_; median photometric redshift of 0.9). We were able to constrain rapid characteristic variability time-scales (~ weeks) using the DES light curves in 15 dwarf AGN candidates (a subset of our variable AGN candidates) at a median photometric redshift of 0.4. This rapid variability is consistent with their low black hole (BH) masses. We confirm the low-mass AGN nature of one source with a high S/N optical spectrum. We publish our catalogue, optical light curves, and supplementary data, such as X-ray properties and optical spectra, when available. We measure a variable AGN fraction versus stellar mass and compare to results from a forward model. This work demonstrates the feasibility of optical variability to identify AGNs with lower BH masses in deep fields, which may be more 'pristine' analogues of supermassive BH seeds.black-holesgalaxiesdwarf-galaxiesactive-galactic-nucleiastrometryphotometryvisible-astronomystellar-massesredshiftedspectroscopyinfrared-astronomyx-ray-sourcesinterdisciplinary-astronomygalactic-and-extragalactic-astronomyhigh-energy-astrophysicsstellar-astronomycosmologyobservational-astronomyhttps://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/MNRAS/516/2736https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/516/27362022MNRAS.516.2736Bhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/516/2736Cone search capability for table J/MNRAS/516/2736/table2 (Variability-selected AGN candidates regardless of stellar mass or variability properties)Cone search capability for table J/MNRAS/516/2736/table3 (Catalogue of 15 variable AGN candidates with rapid variability log({tau}_DRW_)<1.5)Burke C.J.Liu X.Shen Y.Phadke K.A.Yang Q.Hartley W.G.,Harrison I.Palmese A.Guo H.Zhang K.Kron R.Turner D.J.,Giles P.A.Lidman C.Chen Y.-C.Gruendl R.A.Choi A.Amon A.,Sheldon E.Aguena M.Allam S.Andrade-Oliveira F.Bacon D.Bertin E.,Brooks D.Carnero Rosell A.Carrasco Kind M.Carretero J.Conselice C.,Costanzi M.Da Costa L.N.Pereira M.E.S.Davis T.M.De Vicente J.,Desai S.Diehl H.T.Everett S.Ferrero I.Flaugher B.,Garcia-Bellido J.Gaztanaga E.Gruen D.Gschwend J.Gutierrez G.,Hinton S.R.Hollowood D.L.Honscheid K.Hoyle B.James D.J.Kuehn K.,Maia M.A.G.Marshall J.L.Menanteau F.Miquel R.Morgan R.,Paz-Chinchon F.Pieres A.Plazas Malagon A.A.Reil K.Romer A.K.,Sanchez E.Schubnell M.Serrano S.Sevilla-Noarbe I.Smith M.,Suchyta E.Tarle G.Thomas D.To C.Varga T.N.Wilkinson R.D.,(The DES Collaboration)CDS2025https://cds.unistra.fr/vizier-org/licences_vizier.htmlCDS support team <cds-question@unistra.fr>DatasetAstroObjectsastronomy