{"paper":{"title":"PAPER-64 Constraints on Reionization: The 21cm Power Spectrum at z=8.4","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"Aaron R. Parsons, Adrian Liu, Andre Walker, Carina Cheng, Chris L. Carilli, Daniel C. Jacobs, David F. Moore, David H. E. MacMahon, David R. DeBoer, Gianni Bernardi, Haoxuan Zheng, Irina I. Stefan, James E. Aguirre, Jasper Grobbelaar, Jasper Horrell, Jonathan C. Pober, Matthew R. Dexter, Matthys Maree, Nima Razavi, Pat Klima, Richard F. Bradley, William P. Walbrugh, Zaki S. Ali","submitted_at":"2015-02-20T21:39:47Z","abstract_excerpt":"In this paper, we report new limits on 21cm emission from cosmic reionization based on a 135-day observing campaign with a 64-element deployment of the Donald C. Backer Precision Array for Probing the Epoch of Reionization (PAPER) in South Africa. This work extends the work presented in Parsons et al. (2014) with more collecting area, a longer observing period, improved redundancy-based calibration, optimal fringe-rate filtering, and improved power-spectral analysis using optimal quadratic estimators. The result is a new $2\\sigma$ upper limit on $\\Delta^{2}(k)$ of (22.4 mK)$^2$ in the range $0"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1502.06016","kind":"arxiv","version":3},"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"}