Observation of an Unusual Upward-Going Cosmic-Ray-like Event in the Third Flight of ANITA

Journal Article · Thu Oct 18 00:00:00 EDT 2018 · Physical Review Letters

DOI:https://doi.org/10.1103/physrevlett.121.161102· OSTI ID:1490161

Gorham, P. W.; Rotter, B.; Allison, P.; Banerjee, O.; Batten, L.; Beatty, J. J.; Bechtol, K.; Belov, K.; Besson, D. Z.; Binns, W. R.; Bugaev, V.; Cao, P.; Chen, C. C.; Chen, C. H.; Chen, P.; Clem, J. M.; Connolly, A.; Cremonesi, L.; Dailey, B.; Deaconu, C. ; Dowkontt, P. F.; Fox, B. D.; Gordon, J. W. H.; Hast, C.; Hill, B.; Hughes, K.; Huang, J. J.; Hupe, R.; Israel, M. H.; Javaid, A.; Lam, J.; Liewer, K. M.; Lin, S. Y.; Liu, T. C.; Ludwig, A.; Macchiarulo, L.; Matsuno, S.; Miki, C.; Mulrey, K.; Nam, J.; Naudet, C. J.; Nichol, R. J.; Novikov, A.; Oberla, E.; Olmedo, M.; Prechelt, R.; Prohira, S.; Rauch, B. F.; Roberts, J. M.; Romero-Wolf, A.; Russell, J. W.; Saltzberg, D.; Seckel, D.; Schoorlemmer, H.; Shiao, J.; Stafford, S.; Stockham, J.; Stockham, M.; Strutt, B.; Varner, G. S.; Vieregg, A. G.; Wang, S. H.; Wissel, S. A.

We report here on an upward traveling, radio-detected cosmic-ray-like impulsive event with characteristics closely matching an extensive air shower. This event, observed in the third flight of the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload, is consistent with a similar event reported in a previous flight. These events could be produced by the atmospheric decay of an upward-propagating $\tau$ lepton produced by a ${\nu }_{\tau }$ interaction, although their relatively steep arrival angles create tension with the standard model neutrino cross section. Each of the two events have a posteriori background estimates of $\lesssim {10}^{-2}$ events. If these are generated by $\tau$ -lepton decay, then either the charged-current ${\nu }_{\tau }$ cross section is suppressed at EeV energies, or the events arise at moments when the peak flux of a transient neutrino source was much larger than the typical expected cosmogenic background neutrinos.

• Research Organization: SLAC National Accelerator Lab., Menlo Park, CA (United States)
• Sponsoring Organization: National Aeronautics and Space Administration (NASA) (United States); National Science Foundation (NSF) (United States); USDOE; USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
• Contributing Organization: ANITA Collaboration
• Grant/Contract Number: AC02-76SF00515
• OSTI ID: 1490161
• Alternate ID(s): OSTI ID: 1478597
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 16 Vol. 121; ISSN 0031-9007
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

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