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Azimuthal modulation of the event rate of cosmic ray extensive air showers by the geomagnetic field

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 نشر من قبل A. A. Ivanov
 تاريخ النشر 1999
  مجال البحث فيزياء
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The Earths magnetic field effect on the azimuthal distribution of extensive air showers (EAS) of cosmic rays has been evaluated using a bulk of the Yakutsk array data. The uniform azimuthal distribution of the EAS event rate is rejected at the significance level 10^(-14). Amplitude of the first harmonics of observed distribution depends on zenith angle as A1=0.2*sin^2(theta) and is almost independent of the primary energy; the phase coincides with the magnetic meridian. Basing upon the value of measured effect, the correction factor has been derived for the particle density depending on a geomagnetic parameter of a shower.



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