{"paper":{"title":"Sub-part-per-trillion level detection of hydrogen fluoride by cantilever-enhanced photo-acoustic spectroscopy","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["physics.optics"],"primary_cat":"physics.ins-det","authors_text":"Lauri Halonen, Markku Vainio, Teemu Tomberg, Tuomas Hieta","submitted_at":"2017-07-05T10:49:11Z","abstract_excerpt":"We present a highly sensitive hydrogen fluoride detector based on simple cantilever-enhanced photo-acoustic spectroscopy. A noise equivalent concentration of 5 parts-per-trillion was achieved in 1 s and 650 parts-per-quadrillion in 32 min. The limits were reached with an average optical power of 950 mW using a new continuous-wave optical parametric oscillator at 2.476 \\mu m. The achieved normalized noise equivalent absorption coefficient was 2.7$\\times$10$^{-10}$ Wcm$^{-1}$ Hz$^{-1/2}$."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1707.01312","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"}