Askaryan radiation

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The Askaryan radiation [1] [2] [3] [4] also known as Askaryan effect is the phenomenon whereby a particle traveling faster than the phase velocity of light in a dense dielectric (such as salt, ice or the lunar regolith) produces a shower of secondary charged particles which contains a charge anisotropy and emits a cone of coherent radiation in the radio or microwave part of the electromagnetic spectrum. The signal is a result of the Cherenkov radiation from individual particles in the shower. Wavelengths greater than the extent of the shower interfere constructively and thus create a radio or microwave signal which is strongest at the Cherenkov angle. The effect is named after Gurgen Askaryan, a Soviet-Armenian physicist who postulated it in 1962.

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The radiation was first observed experimentally in 2000, 38 years after its theoretical prediction. So far the effect has been observed in silica sand, [5] rock salt, [6] ice, [7] and Earth's atmosphere. [8]

The effect is of primary interest in using bulk matter to detect ultra-high energy neutrinos. The Antarctic Impulse Transient Antenna (ANITA) experiment uses antennas attached to a balloon flying over Antarctica to detect the Askaryan radiation produced as cosmic neutrinos travel through the ice. [9] [10] Several experiments have also used the Moon as a neutrino detector based on detection of the Askaryan radiation. [11] [12] [13] [14]

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References

  1. ↑ Askar'yan, G. A. (1961). "Excess negative charge of an electron-photon shower and its coherent radio emission". Zh. Eksp. Teor. Fiz. 41 (1961): 616--618.
  2. ↑ Askar'yan, G. A. (September 1965). "Coherent Radio Emission from Cosmic Showers in Air and in Dense Media" (PDF). Soviet Physics JETP. 21: 658.
  3. ↑ Hanson, Jordan C; Connolly, Amy L (2016). "Complex Analysis of Askaryan Radiation: A Fully Analytic Treatment including the LPM effect and Cascade Form Factor". Astroparticle Physics. 91: 75–89. arXiv: 1605.04975 . Bibcode:2017APh....91...75H. doi:10.1016/j.astropartphys.2017.03.008. S2CID   118850005.
  4. ↑ Alvarez-Muñiz, Jaime; Romero-Wolf, Andrés; Zas, Enrique (2011-11-11). "Practical and accurate calculations of Askaryan radiation". Physical Review D. 84 (10): 103003. arXiv: 1106.6283 . Bibcode:2011PhRvD..84j3003A. doi:10.1103/PhysRevD.84.103003. ISSN   1550-7998. S2CID   119212570.
  5. ↑ Saltzberg, David; Gorham, P; Walz, D; Field, C; Iverson, R; Odian, A; Resch, G; Schoessow, P; Williams, D (2001). "Observation of the Askaryan Effect: Coherent Microwave Cherenkov Emission from Charge Asymmetry in High Energy Particle Cascades". Physical Review Letters. 86 (13): 2802–5. arXiv: hep-ex/0011001 . Bibcode:2001PhRvL..86.2802S. doi:10.1103/PhysRevLett.86.2802. PMID   11290043. S2CID   5600492.
  6. ↑ Gorham, P. W.; Saltzberg, D.; Field, R. C.; Guillian, E.; Milinčić, R.; Miočinović, P.; Walz, D.; Williams, D. (2005-07-21). "Accelerator measurements of the Askaryan effect in rock salt: A roadmap toward teraton underground neutrino detectors". Physical Review D. 72 (2): 023002. arXiv: astro-ph/0412128 . Bibcode:2005PhRvD..72b3002G. doi:10.1103/PhysRevD.72.023002. ISSN   1550-7998. OSTI   1442457. S2CID   53870487.
  7. ↑ Gorham, P. W.; Barwick, S. W.; Beatty, J. J.; Besson, D. Z.; Binns, W. R.; Chen, C.; Chen, P.; Clem, J. M.; Connolly, A.; Dowkontt, P. F.; DuVernois, M. A. (2007-10-25). "Observations of the Askaryan Effect in Ice". Physical Review Letters. 99 (17): 171101. arXiv: hep-ex/0611008 . Bibcode:2007PhRvL..99q1101G. doi:10.1103/PhysRevLett.99.171101. ISSN   0031-9007. PMID   17995315. S2CID   16332031.
  8. ↑ Buitink, Stijn; Corstanje, A.; Falcke, H; Hörandel, J. R; Huege, T; Nelles, A; Rachen, J. P; Rossetto, L; Schellart, P; Scholten, O; Ter Veen, S; Thoudam, S; Trinh, T. N. G; Anderson, J; Asgekar, A; Avruch, I. M; Bell, M. E; Bentum, M. J; Bernardi, G; Best, P; Bonafede, A; Breitling, F; Broderick, J. W; Brouw, W. N; Brüggen, M; Butcher, H. R; Carbone, D; Ciardi, B; Conway, J. E; et al. (2016). "A large light-mass component of cosmic rays at 1017–1017.5 electronvolts from radio observations". Nature. 531 (7592): 70–3. arXiv: 1603.01594 . Bibcode:2016Natur.531...70B. doi:10.1038/nature16976. PMID   26935696. S2CID   205247687.
  9. ↑ "ANITA Project Overview". Archived from the original on 2015-09-24. Retrieved 2006-06-17.
  10. ↑ "ARIANNA collaboration". Archived from the original on 2016-05-17. Retrieved 2014-11-28.
  11. ↑ GLUE project
  12. ↑ "NuMoon project". Archived from the original on 2009-09-17. Retrieved 2010-02-05.
  13. ↑ LUNASKA project
  14. ↑ RESUN project
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