Document Type : Original Article


Physics Faculty, Semnan University, Semnan, Iran


High energy cosmic rays hitting the earth atmosphere induce extensive air showers propagating downward with a high gamma factor. Determining the core location of such air shower is a necessary step to measure other important characteristics of a cosmic ray such as the lateral distribution function. In this study and based on computer simulations and radio signal analyses we investigate the relation between normalized radio signal phase angle emitted from particles in an air shower to the position of a shower core. We perform a series of simulations based on CORSIKA and COREAS code for cosmic rays with different types of primary particles with an energy range from 0.1 to 1 EeV. The results show a direct relationship between the average slope of normalized radio signal phase angle as a function of frequency to the absolute distance from extensive air shower core location. We have calculated the normalized radio signal phase angle to have the absolute minimum value at close distances to a shower core location. We discuss a possible approach to estimate core location with different types of virtual radio arrays.


  1. K H Kampert and A A Watson, Extensive air showers and ultra high-energy cosmic rays: a historical review. The European Physical Journal H, 37 (3), (2012) 359.

  2. G Rastegarzadeh and H Fallahnejad, Effects of different source characteristics on the propagated CR and secondary neutrino spectra: A CRPropa3 simulation. Advances in Space Research, 63 (12), (2019) 4058.

  3. G Rastegarzadeh and M Nemati, Dependence of the muon pseudorapidity on the cosmic ray mass composition around the knee. International Journal of Modern Physics D 24 (01), (2015) 1550010.

  4. Pierre Auger Collaboration, The Pierre Auger cosmic ray observatory. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 798 (2015) 172.

  5. H Kawai, S Yoshida and H Yoshii, et al., Telescope array experiment. Nuclear Physics B (Proceedings Supplements), (175-176), (2008) 221.

  6. G Rastegarzadeh and M Nemati, Study of the extensive air shower mass sensitive parameters in prototype of ALBORZ array. Advances in Space Research, 55 (6) (2015) 1734.

  7. G Rastegaarzadeh and J Samimi, A wavelet-based multifractal separation technique for extensive air showers. Journal of Physics G: Nuclear and Particle Physics, 27 (10) (2001) 2065.

  8. J V Jelley, J H Fruin, and N A Porter, et al, Radio pulses from extensive cosmic-ray air showers. Nature, 205 (4969) (1965) 327.

  9. Wilson, J.G., Wouthuysen, S.A. and Sard, R.D., 1959. Progress in Elementary Particle and Cosmic Ray Physics. PhT, 12(11), p.46.

  10. D Ardouin, A Belletoile, and D Charrier, et al,. Radioelectric field features of extensive air showers observed with CODALEMA. Astroparticle Physics, 26 (4-5) (2006) 341.

  11. T Huege, Theory and simulations of air shower radio emission. In AIP Conference Proceedings, American Institute of Physics 1535, No. 1 (2013) 121.

  12. M Sabouhi and G Rastegarzadeh, A new method to determine air shower propagation direction based on radio signal patterns. In The 34th International Cosmic Ray Conference, SISSA Medialab, Vol. 236 (2016) 474.

  13. A Corstanje, P Schellart, and A Nelles, et al,. The shape of the radio wavefront of extensive air showers as measured with LOFAR. Astroparticle Physics, 61 (2015) 22.

  14. G Rastegarzadeh and M Sabouhi, SURA: Semnan University Radio Array. Experimental Astronomy, 49(1) (2020) 21.

  15. M Sabouhi and G Rastegarzadeh, The effect of geomagnetic field on radio signal patterns from cosmic ray air showers. In 35th Int. Cosmic Ray Conf.(ICRC) Vol. 301, (2017) 568.

  16. D Heck, J Knapp, J.N Capdevielle, et al,. CORSIKA: A Monte Carlo code to simulate extensive air showers. Report fzka, 6019 (11) (1998).

  17. T Huege, M Ludwig,. and C W James, Simulating radio emission from air showers with CoREAS. In AIP Conference Proceedings, American Institute of Physics. 1535 No 1 (2013) 128.

  18. S Ostapchenko, QGSJET-II: towards reliable description of very high energy hadronic interactions. Nuclear Physics B-Proceedings Supplements, 151(1) (2006)143.

  19. M Sabouhi and G Rastegarzadeh, January. An investigation on the phase angle of radio signals from cosmic ray air showers. In ICRC 301 (2017) 567.

  20. M Sabouhi, and G Rastegarzadeh. "Are inclined air showers from cosmic rays the most suitable to radio detection?." The 34th International Cosmic Ray Conference. 236. SISSA Medialab (2016)



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