{"paper":{"title":"Formation of cometary O$_{2}$ ice and related ice species on grain surfaces in the midplane of the pre-Solar nebula","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.EP","authors_text":"Catherine Walsh, Christian Eistrup","submitted_at":"2018-08-09T20:03:38Z","abstract_excerpt":"[Abridged] The detection of abundant O$_{2}$ ice at 1-10% with respect to H$_{2}$O ice in the comae of comets 1P/Halley and 67P/Churyumov-Gerasimenko motivated attempts to explain the origin of the high O$_{2}$ ice abundance. Recent chemical modelling of the outer, colder regions of a protoplanetary disk midplane has shown production of O$_{2}$ ice at the same abundance as that measured in the comet. An updated chemical kinetics code is utilised here to evolve chemistry under pre-Solar nebula midplane conditions. Four different chemical starting conditions, and the effects of various chemical "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1808.03329","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"}