{"paper":{"title":"LOFAR observations of decameter carbon radio recombination lines towards Cassiopeia A","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"A. G. G. M. Tielens, F. Salgado, H. J. A. R\\\"ottgering, J. B. R. Oonk, K. Emig, L. K. Morabito, M. C. Toribio, P. Salas, R. J. van Weeren","submitted_at":"2017-01-30T19:55:46Z","abstract_excerpt":"We present a study of carbon radio recombination lines towards Cassiopeia A using LOFAR observations in the frequency range 10-33 MHz. Individual carbon $\\alpha$ lines are detected in absorption against the continuum at frequencies as low as 16 MHz. Stacking several C$\\alpha$ lines we obtain detections in the 11-16 MHz range. These are the highest signal-to-noise measurements at these frequencies. The peak optical depth of the C$\\alpha$ lines changes considerably over the 11-33 MHz range with the peak optical depth decreasing from 4$\\times10^{-3}$ at 33 MHz to 2$\\times10^{-3}$ at 11 MHz, while"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1701.08802","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"}