{"paper":{"title":"Antarctic Surface Reflectivity Calculations and Measurements from the ANITA-4 and HiCal-2 Experiments","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"A. Connolly, A. G. Vieregg, A. Ludwig, A. Novikov, A. Romero-Wolf, B. Dailey, B. D. Fox, B. F. Rauch, B. Hill, B. Rotter, B. Strutt, C. Chen, C. Deaconu, C. Hast, C. Miki, D. Saltzberg, D. Seckel, D. Z. Besson, E. Oberla, F. Wu, G. S. Varner, H. Schoorlemmer, J. Gordon, J. J. Beatty, J. Lam, J. M. Clem, J. Nam, J. Russell, J. Stockham, K. Belov, K. Mulrey, K. Ratzlaff, K. Tatem, L. Batten, L. Cremonesi, M. H. Israel, M. Mottram, M. Stockham, O. Banerjee, P. Allison, P. Cao, P. Chen, P. Dasgupta, P. F. Dowkontt, P. Jain, P. W. Gorham, R. Hupe, R. J. Nichol, R. Young, S. A. Wissel, S. Matsuno, S. Nande, S. Prohira, S. Stafford, T. C. Liu, V. Bugaev, W. R. Binns","submitted_at":"2018-01-26T17:36:54Z","abstract_excerpt":"The balloon-borne HiCal radio-frequency (RF) transmitter, in concert with the ANITA radio-frequency receiver array, is designed to measure the Antarctic surface reflectivity in the RF wavelength regime. The amplitude of surface-reflected transmissions from HiCal, registered as triggered events by ANITA, can be compared with the direct transmissions preceding them by O(10) microseconds, to infer the surface power reflection coefficient $\\cal{R}$. The first HiCal mission (HiCal-1, Jan. 2015) yielded a sample of 100 such pairs, resulting in estimates of $\\cal{R}$ at highly-glancing angles (i.e., "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1801.08909","kind":"arxiv","version":1},"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"}