Askaryan Radio Array

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The Askaryan Radio Array (ARA) is a new detector designed to detect a few GZK neutrinos a year. It measures the enhanced radio-frequency radiation emitted during the interaction of the neutrino in Antarctic ice sheet. The detection is based on the Askaryan effect, an idea by Gurgen Askaryan [1] [2]

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This detection technique is also being used by the Antarctic Impulse Transient Antenna (ANITA) and the Radio Ice Cerenkov Experiment (RICE) detectors. The ARA experiment will be built around the IceCube experiment, and will cover an area of approximately 100 square kilometers.

A 16-antenna prototype station, the "ARA Testbed" , of the ARA system was installed January 2011 (season 2010–2011) and began operation allowing the ARA Collaboration to determine the estimated sensitivity of the array design: [3] ARA-37 will cover 200 km2 with neutrino sensitivity of 1016–1019 eV. Measurements of the radio background and ice attenuation length were reported.

The first ARA station was installed in the season (Antarctic summer season; winter in northern hemisphere) 2011–2012; stations 2 and 3 were installed in the season 2012–2013 and stations 4 and 5 in season 2017–2018. The ARA array had five stations as of 2018. The Phase 1 goal of ARA is 37 stations. [4]

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References

  1. G.A. Askaryan (1962). "Excess Negative Charge of an Electron-Photon Shower And Its Coherent Radio Emission". Soviet Physics JETP . 14 (2): 441–443.
  2. G.A. Askaryan (1965). "Coherent Radio Emission from Cosmic Showers in Air and in Dense Media". Soviet Physics JETP . 21 (3): 658. Bibcode:1965JETP...21..658A.
  3. P. Allison; J. Auffenberg; R. Bard; J.J. Beatty; D.Z. Besson; S. Böser; C. Chen; P. Chen; A. Connolly; J. Davies; M. DuVernois; B. Fox; P.W. Gorham; E.W. Grashorn; K. Hanson; J. Haugen; K. Helbing; B. Hill; K.D. Hoffman; E. Hong; M. Huang; M.H.A. Huang; A. Ishihara; A. Karle; D. Kennedy; H. Landsman; T.C. Liu; L. Macchiarulo; K. Mase; T. Meures; R. Meyhandan; C. Miki; R. Morse; M. Newcomb; R.J. Nichol; K. Ratzlaff; M. Richman; L. Ritter; C. Rott; B. Rotter; P. Sandstrom; D. Seckel; J. Touart; G.S. Varner; M.-Z. Wang; C. Weaver; A. Wendorff; S. Yoshida; R. Young (February 2012). "Design and initial performance of the Askaryan Radio Array prototype EeV neutrino detector at the South Pole". Astroparticle Physics. 35 (7): 457. arXiv: 1105.2854 . Bibcode:2012APh....35..457A. doi:10.1016/j.astropartphys.2011.11.010.
  4. "ARENA 2018 – Acoustic and Radio EeV Neutrino Detection Activities (12–15 June 2018) · Indico".

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