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arXiv · 0812.2715

New Limits on the Ultra-high Energy Cosmic Neutrino Flux from the ANITA Experiment

ANITA collaboration·P. Gorham·P. Allison·S. Barwick·J. Beatty·D. Besson·W. Binns·C. Chen·P. Chen·J. Clem·A. Connolly·P. Dowkontt·M. DuVernois·R. Field·D. Goldstein·A. Goodhue·C. Hast·C. Hebert·S. Hoover·M. Israel·J. Kowalski·J. Learned·K. Liewer·J. Link·E. Lusczek·S. Matsuno·B. Mercurio·C. Miki·P. Miocinovic·J. Nam·C. Naudet·R. Nichol·K. Palladino·K. Reil·A. Romero-Wolf·M. Rosen·L. Ruckman·D. Saltzberg·D. Seckel·G. Varner·D. Walz·Y. Wang·F. Wu
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Abstract

We report initial results of the first flight of the Antarctic Impulsive Transient Antenna (ANITA-1) 2006-2007 Long Duration Balloon flight, which searched for evidence of a diffuse flux of cosmic neutrinos above energies of 3 EeV. ANITA-1 flew for 35 days looking for radio impulses due to the Askaryan effect in neutrino-induced electromagnetic showers within the Antarctic ice sheets. We report here on our initial analysis, which was performed as a blind search of the data. No neutrino candidates are seen, with no detected physics background. We set model-independent limits based on this result. Upper limits derived from our analysis rule out the highest cosmogenic neutrino models. In a background horizontal-polarization channel, we also detect six events consistent with radio impulses from ultra-high energy extensive air showers.

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ANITA collaboration, P. Gorham, P. Allison, S. Barwick, J. Beatty, D. Besson, W. Binns, C. Chen, P. Chen, J. Clem, A. Connolly, P. Dowkontt, M. DuVernois, R. Field, D. Goldstein, A. Goodhue, C. Hast, C. Hebert, S. Hoover, M. Israel, J. Kowalski, J. Learned, K. Liewer, J. Link, E. Lusczek, S. Matsuno, B. Mercurio, C. Miki, P. Miocinovic, J. Nam, C. Naudet, R. Nichol, K. Palladino, K. Reil, A. Romero-Wolf, M. Rosen, L. Ruckman, D. Saltzberg, D. Seckel, G. Varner, D. Walz, Y. Wang, F. Wu. 2008-12-15. New Limits on the Ultra-high Energy Cosmic Neutrino Flux from the ANITA Experiment. https://doi.org/10.1103/physrevlett.103.051103

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