{"paper":{"title":"Very high-energy observations of the two high-frequency peaked BL Lac objects 1ES 1218+304 and H 1426+428","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["hep-ex"],"primary_cat":"astro-ph.HE","authors_text":"A. Jarvis, C.E. Covault, C. Mueller, D.A. Bramel, D.A. Williams, D. Driscoll, D.M. Gingrich, D.S. Hanna, J. Ball, J. Carson, J. Kildea, J. Zweerink (The STACEE Collaboration), K. Ragan, N. Akhter, P. Fortin, R.A. Ong, R.A. Scalzo, R. Mukherjee, T. Lindner","submitted_at":"2011-04-14T14:12:27Z","abstract_excerpt":"We present results of very-high-energy gamma-ray observations (E > 160 GeV) of two high-frequency-peaked BL Lac (HBL) objects, 1ES 1218+304 and H 1426+428, with the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE). Both sources are very-high-energy gamma-ray emitters above 100 GeV, detected using ground-based Cherenkov telescopes. STACEE observations of 1ES 1218+304 and H 1426+428 did not produce detections; we present 99% CL flux upper limits for both sources, assuming spectral indices measured mostly at higher energies."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1104.2770","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"}