Liveme and sensivity of the ARIANNA Hexagonal Array Background emission Operaons Department of Physics and Astronomy, University of California Irvine, CA, USA Cosmic Rays υ Date, time (UTC) 20-00h 20-12h 21-00h 21-12h 22-00h 22-12h Frequency [GHz] 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Recorded Amplitude [mV] 10 20 30 40 50 60 70 80 90 Date Dec 18 Jan 01 Jan 15 Jan 29 Feb 12 Feb 26 Mar 11 Mar 25 Apr 08 Apr 22 Fraction of Day 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Stn Livetime Above 0 Deg Above 2.5 Deg Above 5 Deg Above 7.5 Deg Above 10 Deg Above 12.5 Deg Site B Date Dec 18 Jan 01 Jan 15 Jan 29 Feb 12 Feb 26 Mar 11 Mar 25 Apr 08 Apr 22 Fraction of Day 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Stn Livetime Above 0 Deg Above 2.5 Deg Above 5 Deg Above 7.5 Deg Above 10 Deg Above 12.5 Deg Site C Strong solar burst of December 2014 visible in ARIANNA antennas Burst caused Aurorae that are also visble Antenna detects different areas of Galacc emission during one day Variaon a result of folding the Galacc emission paern with antenna sensivty Array status and hardware 7 staons with four downward point - ing antennas operaonal since 2014 1 staon with two upward poinng antennas for background studies of lower frequencies (site X) Communicaon via long-range wifi and/or Iridium saelites Next-generaon boards for data-acquision, SST 4 channels of 256 samples 2 Giga-samples per second Band of 0.1 - 1 GHz 32 GB of solid state memory Remotely programmable 12 bits of dynamic range Power consumpon less than 6 Was per staon 1 mV RMS trigger sensivity at > 600 MHz trigger band Power and Communicaon Tower for one ARINNA staon on the Ross Ice-Shelf Ultra-high energy cosmic protons will generate neutrinos in interacon with the Cosmic Microwave Background ARIANNA is designed to detect neutrinos at these energies (> 10 7 GeV) [1,2] ARIANNA is also sensive to radio emis- sion of air showers Important/only background at site on the Ross Ice Shelf Extensive Monte Carlo study underway to determine thresholds for air shower detecon Threshold depends on energy and the distance to the shower maximum Upward facing antennas as addional veto for air showers installed First cosmic ray candidates idenfied CoREAS simulaon Storm at the ARIANNA site Repeated failure to establish wifi communicaon Rare hardware issue inter - rupted running of staons, fixed remotely in February No sunlight aſter April 21st Plans for next season Install baeries and newest boards at all staons inside the electronics boxes Run solely on Iridium communicaon to study prospects of low power operaon Improve on cosmic ray idenficaon, study antenna sensivity in ice Explore potenal of lower frequencies (> 50 MHz) Future plans Build the full ARIANNA: extend array to 1000 staons Every staon will be an autonomous and independent neutrino detector [1] S.W. Barwick et al., Astro.Part.Phys. 70 (2015) 12-26 [2] C. Reed for the ARIANNA Collaboraon, PoS(ICRC2015)1149, Board: 279 [3] S.W. Barwick et al., IEEE Trans. on Nucl. Sc. (in press) (2015) [4] S.A. Kleinfelder et al., Proc. IEEE Nucl. Sc. Symp. Seale, WA (2014) Simulaons: CORSIKA 7.4005, QGSJET-II-04, FLUKA ARIANN A Anna Nelles and Chris Persichilli for the ARIANNA Collaboraon E [eV] 17 10 18 10 19 10 20 10 ] 1.7 eV -1 sr -1 s -2 J(E) [m ⋅ 2.7 E 15 10 16 10 17 10 18 10 19 10 20 10 21 10 22 10 23 10 Pierre Auger Coll. (2013) HiRes I (2007) HiRes II (2007) KASCADE Grande (2012) KASCADE (2005) IceTop (2013) TA (2012) Liveme with baery Liveme without baery Liveme > 90%, limited by communicaon windows Enourmous gain in live- me by using a backup baery Details in [3,4] Sunlight at ARIANNA site Downward poinng antennas see no flucaon due to posion and back-lobe suppression