{"paper":{"title":"Remarks on the light ring images and the optical appearance of hairy black holes in Einstein-Maxwell-dilaton gravity","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"gr-qc","authors_text":"Chatchai Promsiri, Ekapong Hirunsirisawat, Weerawit Horinouchi","submitted_at":"2023-10-06T13:09:50Z","abstract_excerpt":"The behaviors of null geodesics in the spherical symmetric black holes in Einstein-Maxwell-dilaton (EMD) theory with coupling function $f(\\Phi)=e^{-2\\alpha \\Phi}$ are meticulously analyzed. We investigate the effects of coupling constant $\\alpha$ on the effective potential of photon trajectories within three ranges, namely $0<\\alpha <1$, $\\alpha =1$ and $\\alpha >1$. We find that the thicknesses of lensing and photon rings are smaller at larger $\\alpha$ and fixed electric charge in the unit of mass $q$, whereas they are larger at fixed $\\alpha$ and larger $q$. This behavior can be described by "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2310.04221","kind":"arxiv","version":3},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2310.04221/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}