Experimental tests of sub-surface reflectors as an explanation for the ANITA anomalous events
D. Smith, D. Z. Besson, C. Deaconu, S. Prohira, P. Allison, L. Batten, J. J. Beatty, W. R. Binns, V. Bugaev, P. Cao, C. Chen, P. Chen, J. M. Clem, A. Connolly, … 展开作者
D. Smith, D. Z. Besson, C. Deaconu, S. Prohira, P. Allison, L. Batten, J. J. Beatty, W. R. Binns, V. Bugaev, P. Cao, C. Chen, P. Chen, J. M. Clem, A. Connolly, L. Cremonesi, P. Dasgupta, P. W. Gorham, M. H. Israel, T. C. Liu, A. Ludwig, S. Matsuno, C. Miki, J. Nam, A. Novikov, R. J. Nichol, E. Oberla, R. Prechelt, B. F. Rauch, J. Russell, D. Saltzberg, D. Seckel, G. S. Varner, A. G. Vieregg, S. A. Wissel
The balloon-borne ANITA experiment is designed to detect ultra-high energy neutrinos via radio emissions produced by an in-ice shower. Although initially purposed for interactions within the Antarctic ice sheet, ANITA also demonstrated the ability to self-trigger on radio emissions from ultra-high energy charged cosmic rays interacting in the Earth's atmosphere. For showers produced above the Antarctic ice sheet, reflection of the down-coming radio signals at the Antarctic surface should result in a polarity inversion prior to subsequent observation at the $\sim$35-40 km altitude ANITA gondola. ANITA has published two anomalous instances of upcoming cosmic-rays with measured polarity opposite the remaining sample of $\sim$50 UHECR signals. The steep observed upwards incidence angles (25--30 degrees relative to the horizontal) require non-Standard Model physics if these events are due to in-ice neutrino interactions, as the Standard Model cross-section would otherwise prohibit neutrinos from penetrating the long required chord of Earth. Shoemaker et al. posit that glaciological effects may explain the steep observed anomalous events. We herein consider the scenarios offered by Shoemaker et al. and find them to be disfavored by extant ANITA and HiCal experimental data. We note that the recent report of four additional near-horizon anomalous ANITA-4 events, at $>3σ$ significance, are incompatible with their model, which requires significant signal transmission into the ice.
Coherent transition radiation from the geomagnetically-induced current in cosmic-ray air showers: Implications for the anomalous events observed by ANITA
Exact spherical-wave forward model for radio reflection from stratified media and implications for the anomalous-polarity events observed by ANITA
Center for Cosmology and AstroParticle Physics (CCAPP), Ohio State University（俄亥俄州立大学宇宙学与天体粒子物理中心）；Department of Physics, Ohio State University（俄亥俄州立大学物理系）；Department of Astronomy, Ohio State University（俄亥俄州立大学天文系）
ICECUBE对高能宇宙中微子的观测开创了超越标准模型探索宇宙和新物理的新纪元。在标准图中，虽然大部分$ν_μ$和$ν_e$是在源中产生的，但振荡将产生$ν_τ$ { \it en route}。某些超越SM的场景，比如与超轻型DM的交互，可以改变这种情况。因此，宇宙中微子流的味道成分可以打开探索某些超出SM场景的可能性，否则是无法进入的。我们表明，$τ$味在中微子味中占有特殊的地位，在阐明新的物理。将ANITA观察到的两个异常事件解释为$ν_τ$事件，使得tau的味道更加有趣。我们研究了如何检测的两个tau事件的ICECUBE约束的中微子与超轻暗物质的相互作用，并讨论了这种相互作用的影响，甚至更高的能量宇宙中微子可探测的未来射电望远镜，如ARA，ARIANNA和GRAND。我们还重新审视了$3+1$中微子计划作为一个解决方案的两个异常ANITA事件，并澄清了一个误解，存在于文献中的高能中微子在物质中的演化的$3+1$计划与散射的可能性核。我们表明，现有的界限上的磁通量的$ν_τ$与EeV的能量排除了这种解决方案的ANITA事件。我们表明，$3+1$解决方案可以保存从这个约束和约束的额外的相对论自由度在早期宇宙中打开的中微子与超轻暗物质的相互作用。
