{"paper":{"title":"Performance measurement of HARPO: a Time Projection Chamber as a gamma-ray telescope and polarimeter","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["hep-ex","physics.ins-det"],"primary_cat":"astro-ph.IM","authors_text":"A. Delbart, A. Takemoto, B. Giebels, D. Atti\\'e, D. Baudin, D. Bernard, D. Calvet, D. G\\\"otz, D. Horan, F. Magniette, H. Ohkuma, I. Semeniouk, M. Frotin, M. Louzir, M. Yamaguchi, P. Baron, P. Bruel, P. Colas, P. Gros, P. Poilleux, P. Sizun, R. Yonamine, S. Amano, S. Dat\\'e, S. Hashimoto, S. Miyamoto, S. Wang, T. Kotaka, Y. Geerebaert, Y. Minamiyama","submitted_at":"2017-06-20T14:33:59Z","abstract_excerpt":"We analyse the performance of a gas time projection chamber (TPC) as a high-performance gamma-ray telescope and polarimeter in the e$^+$e$^-$ pair creation regime. We use data collected at a gamma-ray beam of known polarisation. The TPC provides two orthogonal projections $(x,z)$ and $(y,z)$ of the tracks induced by each conversion in the gas volume. We use a simple vertex finder in which vertices and pseudo-tracks exiting from them are identified.\n  We study the various contributions to the single-photon angular resolution using Monte Carlo simulations and compare them with the experimental d"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1706.06483","kind":"arxiv","version":2},"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"}