{"paper":{"title":"AGN predictions for the Hubble Deep Field and the X-ray background","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"A.C. Fabian (Institute of Astronomy, Cambridge, O. Almaini, UK)","submitted_at":"1997-04-14T17:19:52Z","abstract_excerpt":"We estimate the number of AGN among the galaxies in the Hubble Deep Field (HDF). The recent discovery of a class of X-ray luminous narrow emission-line galaxies has provided a possible explanation for the origin of the X-ray background (XRB), although the nature of the activity is still unresolved. By extrapolating the observed X-ray number count distribution to faint optical magnitudes we predict that this AGN population could account for a significant fraction, $\\sim 10$ per cent, of the galaxies in the HDF. In contrast, normal broad line QSOs are expected to account for no more than $\\sim 0"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9704128","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"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"}