{"paper":{"title":"Optical Spectroscopic Observations of Gamma-ray Blazar Candidates. V. TNG, KPNO, and OAN Observations of Blazar Candidates of Uncertain Type in the Northern Hemisphere","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"A. Paggi (SAO), E. Jim\\'enez-Bail\\'on (UNAM), F. La Franca (UniRomaTRE), F. Massaro (UniTO-INFN-TO), F. Ricci (UniRomaTRE), G. Tosti (UniPG), Howard A. Smith (SAO), J. Torrealba (INAOE), L. Latronico (INFN-TO), M. Landoni (INAF), N. \\'Alvarez Crespo (UniTO-INFN), N. Masetti (INAF-IASF-BO), R. D'Abrusco (SAO), V. Chavushyan (INAOE), V. Pati\\~no-\\'Alvarez (INAOE)","submitted_at":"2016-09-15T20:00:15Z","abstract_excerpt":"The extragalactic $\\gamma$-ray sky is dominated by emission from blazars, a peculiar class of active galactic nuclei (AGNs). Many of the $\\gamma$-ray sources included in Fermi -Large Area Telescope Third Source catalog (3FGL) are classified as a blazar candidate of uncertain type (BCU) because there is no optical spectra available in the literature to confirm their nature. In 2013 we started a spectroscopic campaign to look for the optical counterparts of the BCUs and of the Unidentified $\\gamma$-ray Sources. The main goal of our investigation is to confirm the blazar nature of these sources h"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1609.04829","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"}