Characteristics of Four Upward-pointing Cosmic-ray-like Events Observed with ANITA

P. W. Gorham; J. Nam; A. Romero-Wolf; S. Hoover; P. Allison; O. Banerjee; J. J. Beatty; K. Belov; D. Z. Besson; W. R. Binns; V. Bugaev; P. Cao; C. Chen; P. Chen; J. M. Clem; A. Connolly; B. Dailey; C. Deaconu; L. Cremonesi; P. F. Dowkonnt; M. A. Duvernois; R. C. Field; B. D. Fox; D. Goldstein; J. Gordon; C. Hast; C. L. Hebert; B. Hill; K. Hughes; R. Hupe; M. H. Israel; A. Javaid; J. Kowalski; J. Lam; J. G. Learned; K. M. Liewer; T. C. Liu; J. T. Link; E. Lusczek; S. Matsuno; B. C. Mercurio; C. Miki; P. Miocinovic; M. Mottram; K. Mulrey; C. J. Naudet; J. Ng; R. J. Nichol; K. Palladino; B. F. Rauch; K. Reil; J. Roberts; M. Rosen; B. Rotter; J. Russell; L. Ruckman; D. Saltzberg; D. Seckel; H. Schoorlemmer; S. Stafford; J. Stockham; M. Stockham; B. Strutt; K. Tatem; G. S. Varner; A. G. Vieregg; D. Walz; S. A. Wissel; F. Wu

doi:10.1103/physrevlett.117.071101

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arXiv · 1603.05218

Characteristics of Four Upward-pointing Cosmic-ray-like Events Observed with ANITA

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Abstract

We report on four radio-detected cosmic-ray (CR) or CR-like events observed with the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload. Two of the four were previously identified as stratospheric CR air showers during the ANITA-I flight. A third stratospheric CR was detected during the ANITA-II flight. Here we report on characteristics these three unusual CR events, which develop nearly horizontally, 20-30~km above the surface of the Earth. In addition, we report on a fourth steeply upward-pointing ANITA-I CR-like radio event which has characteristics consistent with a primary that emerged from the surface of the ice. This suggests a possible $\tau$-lepton decay as the origin of this event, but such an interpretation would require significant suppression of the Standard Model ${\tau}$-neutrino cross section.

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P. W. Gorham, J. Nam, A. Romero-Wolf, S. Hoover, P. Allison, O. Banerjee, J. J. Beatty, K. Belov, D. Z. Besson, W. R. Binns, V. Bugaev, P. Cao, C. Chen, P. Chen, J. M. Clem, A. Connolly, B. Dailey, C. Deaconu, L. Cremonesi, P. F. Dowkonnt, M. A. Duvernois, R. C. Field, B. D. Fox, D. Goldstein, J. Gordon, C. Hast, C. L. Hebert, B. Hill, K. Hughes, R. Hupe, M. H. Israel, A. Javaid, J. Kowalski, J. Lam, J. G. Learned, K. M. Liewer, T. C. Liu, J. T. Link, E. Lusczek, S. Matsuno, B. C. Mercurio, C. Miki, P. Miocinovic, M. Mottram, K. Mulrey, C. J. Naudet, J. Ng, R. J. Nichol, K. Palladino, B. F. Rauch, K. Reil, J. Roberts, M. Rosen, B. Rotter, J. Russell, L. Ruckman, D. Saltzberg, D. Seckel, H. Schoorlemmer, S. Stafford, J. Stockham, M. Stockham, B. Strutt, K. Tatem, G. S. Varner, A. G. Vieregg, D. Walz, S. A. Wissel, F. Wu. 2016-03-16. Characteristics of Four Upward-pointing Cosmic-ray-like Events Observed with ANITA. https://doi.org/10.1103/physrevlett.117.071101

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