{"paper":{"title":"X-Ray Properties of Narrow-Line Seyfert 1 Galaxies with Very Small Broad-Line Widths","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"H. Y. Zhou, S. H. Zhang, T. G. Wang, W. Yuan, Y. L. Ai","submitted_at":"2010-11-15T03:39:57Z","abstract_excerpt":"Narrow-line Seyfert\\,1 galaxies (NLS1s) with very small broad-line widths (say, FWHM(\\hb) $\\la $ 1200\\,\\kms) represent the extreme type of Seyfert\\,1 galaxies that have small black hole masses (\\mbh) and/or high Eddington ratios (\\redd). Here we study the X-ray properties of a homogeneously and optically selected sample of 13 such objects, termed as very narrow line Seyfert\\,1 galaxies (VNLS1s), using archival \\xmm\\ data. It is found that the Fe K$\\alpha$ emission line is at most weak in these objects. A soft X-ray excess is ubiquitous, with the thermal temperatures falling within a strict ran"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1011.3283","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":""},"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"}