{"paper":{"title":"JCMT BISTRO Survey observations of the Ophiuchus Molecular Cloud: Dust grain alignment properties inferred using a Ricean noise model","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Archana Soam, Chakali Eswaraiah, Chang Won Lee, Derek Ward-Thompson, Gwanjeong Kim, James Di Francesco, Jia-Wei Wang, Kate Pattle, Lapo Fanciullo, Masafumi Matsumura, Pierre Bastien, Ray Furuya, Sarah Sadavoy, Sheng-Yuan Liu, Shih-Ping Lai, Simon Coud\\'e, Takashi Onaka, Tetsuo Hasegawa, Thiem Hoang, Tie Liu, Woojin Kwon","submitted_at":"2019-06-08T05:07:36Z","abstract_excerpt":"The dependence of polarization fraction $p$ on total intensity $I$ in polarized submillimeter emission measurements is typically parameterized as $p\\propto I^{-\\alpha}$ $(\\alpha \\leq 1)$, and used to infer dust grain alignment efficiency in star-forming regions, with an index $\\alpha=1$ indicating near-total lack of alignment of grains with the magnetic field. In this work we demonstrate that the non-Gaussian noise characteristics of polarization fraction may produce apparent measurements of $\\alpha \\sim 1$ even in data with significant signal-to-noise in Stokes $Q$, $U$ and $I$ emission, and "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1906.03391","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/1906.03391/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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"}