scholarly journals Computation of ion production rate profiles induced by cosmic rays during Bastille day 14 July 2000 ground level enhancement

2016 ◽  
Author(s):  
Peter Velinov ◽  
Alexander Mishev
Keyword(s):  
Cosmic Rays ◽  
Production Rate ◽  
Ground Level ◽  
Ground Level Enhancement ◽  
Ion Production

scholarly journals Short- and Medium-Term Induced Ionization in the Earth Atmosphere by Galactic and Solar Cosmic Rays

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Alexander Mishev
Keyword(s):  
Cosmic Rays ◽  
Cosmic Ray ◽  
Ground Level ◽  
Galactic Cosmic Rays ◽  
Earth Atmosphere ◽  
Medium Term ◽  
Ground Level Enhancement ◽  
Solar Cosmic Rays ◽  
The Earth ◽  
Ionization Effect

The galactic cosmic rays are the main source of ionization in the troposphere of the Earth. Solar energetic particles of MeV energies cause an excess of ionization in the atmosphere, specifically over polar caps. The ionization effect during the major ground level enhancement 69 on January 20, 2005 is studied at various time scales. The estimation of ion rate is based on a recent numerical model for cosmic-ray-induced ionization. The ionization effect in the Earth atmosphere is obtained on the basis of solar proton energy spectra, reconstructed from GOES 11 measurements and subsequent full Monte Carlo simulation of cosmic-ray-induced atmospheric cascade. The evolution of atmospheric cascade is performed with CORSIKA 6.990 code using FLUKA 2011 and QGSJET II hadron interaction models. The atmospheric ion rate is explicitly obtained for various latitudes, namely, 40°N, 60°N and 80°N. The time evolution of obtained ion rates is presented. The short- and medium-term ionization effect is compared with the average effect due to galactic cosmic rays. It is demonstrated that ionization effect is significant only in subpolar and polar atmosphere during the major ground level enhancement of January 20, 2005. It is negative in troposphere at midlatitude, because of the accompanying Forbush effect.

scholarly journals Cosmic Ray Evidence for the Magnetic Configuration of the Heliosphere

1981 ◽  
Vol 94 ◽  
pp. 397-398
Author(s):  
H. S. Ahluwalia
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Cosmic Rays ◽  
Cosmic Ray ◽  
Ground Level ◽  
The Sun ◽  
Ground Level Enhancement ◽  
Solar Cosmic Rays ◽  
Pile Up ◽  
Scattered Component

Sekido and Murakami (1958) proposed the existence of the heliosphere to explain the scattered component of the solar cosmic rays. The heliosphere of their conception is a spherical shell around the sun. The shell contains a highly-irregular magnetic field and serves to scatter the cosmic rays emitted by the sun. It thereby gives rise to an isotropic component of solar cosmic rays, following the maximum in the ground level enhancement (GLE). Meyer et al. (1956) showed that a similar picture applies to the GLE of 23 February 1956. They conclude that the inner and outer radii of the shell should be 1.4 AU and 5 AU respectively. They suggest that a shell is formed by the “pile-up” of the solar wind under pressure exerted by the interstellar magnetic field, as suggested by Davis (1955).

scholarly journals GLE events in 24th solar cycle

2018 ◽  
Vol 62 ◽  
pp. 01006
Author(s):  
Yury Balabin ◽  
Boris Gvozdevsky ◽  
Aleksei Germanenko ◽  
Eugeny Maurchev
Keyword(s):  
Solar Cycle ◽  
Cosmic Rays ◽  
Ground Level ◽  
Energy Spectra ◽  
Special Technique ◽  
Neutron Monitors ◽  
Ground Level Enhancement ◽  
Solar Cosmic Rays ◽  
The World ◽  
Current Cycle

Started in 2009, the 24th solar cycle is going to end. In 2015, the solar activity was at its maximum, turning down. According to many indices, this cycle turned out to be abnormal. For instance, in the previous, the 23rd cycle, the index such as the number of solar spots was as high as 175, compared with that of the 24th cycle, not exceeding 100. According to the number of GLE-events (ground level enhancement of solar cosmic rays, observed on neutron monitors), the current cycle also differs greatly from the previous ones. In the 23rd cycle, the number of great GLE-events was as high as four, and that of small and moderate being five. In the 24th cycle, only two GLE-events were recorded: GLE 71 (17.05.2012) и GLE 72 (10.09.2017), with the last event being of small amplitude (5%). The presence of the neutron monitors network data enables calculation of the energy spectrum and other parameters of solar cosmic rays. The GLEevents are processed by special technique developed at PGI. It is aimed at solving the inverse problem: based on the data from the world neutron monitors network, to obtain the parameters of solar cosmic rays energy spectra. Like the previous ones, GLE-events 71 and 72 were processed by this technique. The energetic spectra obtained were compared with those in other events of the previous cycles

scholarly journals Solar cosmic rays during the extremely high ground level enhancement on 23 February 1956

2005 ◽  
Vol 23 (6) ◽  
pp. 2281-2291 ◽  
Author(s):  
A. Belov ◽  
E. Eroshenko ◽  
H. Mavromichalaki ◽  
C. Plainaki ◽  
V. Yanke
Keyword(s):  
Cosmic Rays ◽  
Particle Density ◽  
Cosmic Ray ◽  
Ground Level ◽  
Particle Energy ◽  
Ground Level Enhancement ◽  
Solar Cosmic Rays ◽  
Solar Particle ◽  
Small Width ◽  
Standard Design

Abstract. The 23 February 1956 ground level enhancement of the solar cosmic ray intensity (GLE05) is the most famous among the proton events observed since 1942. But we do not have a great deal of information on this event due to the absence of solar wind and interplanetary magnetic field measurements at that time. Furthermore, there were no X-Ray or gamma observations and the information on the associated flare is limited. Cosmic ray data was obtained exclusively by ground level detectors of small size and in some cases of a non-standard design. In the present work all available data from neutron monitors operating in 1956 were analyzed, in order to develop a model of the solar cosmic ray behavior during the event. The time-dependent characteristics of the cosmic ray energy spectrum, cosmic ray anisotropy, and differential and integral fluxes have been evaluated utilizing different isotropic and anisotropic models. It is shown that the most outstanding features of this proton enhancement were a narrow and extremely intense beam of ultra-relativistic particles arriving at Earth just after the onset and the unusually high maximum solar particle energy. However, the contribution of this beam to the overall solar particle density and fluency was not significant because of its very short duration and small width. Our estimate of the integral flux for particles with energies over 100 MeV places this event above all subsequent. Perhaps the number of accelerated low energy particles was closer to a record value, but these particles passed mainly to the west of Earth. Many features of this GLE are apparently explained by the peculiarity of the particle interplanetary propagation from a remote (near the limb) source. The quality of the available neutron monitor data does not allow us to be certain of some details; these may be cleared up by the incorporation into the analysis of data from muonic telescopes and ionization chambers operating at that time. Keywords. Interplanatary physics (Cosmic rays; Energetic particles) – Solar physics, astrophysics and astronomy (Flares and mass injections)

Ground-level enhancement of solar cosmic rays on October 28, 2003: A mechanism of the generation of particles in the sun

JETP Letters ◽  
2015 ◽  
Vol 102 (6) ◽  
pp. 335-342 ◽  
Author(s):  
G. F. Krymsky ◽  
V. G. Grigoryev ◽  
S. A. Starodubtsev ◽  
S. N. Taneev
Keyword(s):  
Cosmic Rays ◽  
Ground Level ◽  
The Sun ◽  
Ground Level Enhancement ◽  
Solar Cosmic Rays

scholarly journals The event of ground level enhancement of solar cosmic rays on October 28, 2003: the spectrum in a wide energy range.

2016 ◽  
Author(s):  
Petr Yurievich Gololobov ◽  
Vladislav Grigoryev ◽  
Sergey Starodubtsev ◽  
Sergey Taneev ◽  
Germogen Krymsky
Keyword(s):  
Cosmic Rays ◽  
Energy Range ◽  
Ground Level ◽  
Wide Energy Range ◽  
Ground Level Enhancement ◽  
Solar Cosmic Rays ◽  
Wide Energy
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