{"paper":{"title":"A deep search for molecular gas in two massive Lyman break galaxies at z=3 and 4: vanishing CO-emission due to low metallicity?","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"CEA-Saclay), CFHT), Chris L. Carilli (NRAO), David Elbaz (CEA-Saclay), Dominik A. Riechers (Cornell), Emanuele Daddi (CEA-Saclay), Fabian Walter (MPIA), Frazer N. Owen (NRAO), Frederic Bournaud (CEA-Saclay), Georgios Magdis (Oxford), Glenn E. Morrison (IfA, Helmut Dannerbauer (Vienna), Jacqueline A. Hodge (MPIA), Mark Dickinson (NOAO), Mark T. Sargent (CEA-Saclay), Matthieu Bethermin (CEA-Saclay), Maurilio Pannella (CEA-Saclay), Qinghua Tan (PMO, Yu Gao (PMO)","submitted_at":"2013-09-21T08:17:15Z","abstract_excerpt":"We present deep IRAM Plateau de Bure Interferometer (PdBI) observations, searching for CO-emission toward two massive, non-lensed Lyman break galaxies (LBGs) at z=3.216 and 4.058. With one low significance CO detection (3.5 sigma) and one sensitive upper limit, we find that the CO lines are >~ 3-4 times weaker than expected based on the relation between IR and CO luminosities followed by similarly, massive galaxies at z=0-2.5. This is consistent with a scenario in which these galaxies have low metallicity, causing an increased CO-to-H_2 conversion factor, i.e., weaker CO-emission for a given m"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1309.5448","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"}