Parameterization of cosmic radiation at sea level

Astrophysics and Space Science

The flux rate of cosmic rays incident on the Earth's upper atmosphere is modulated by the solar wind and the Earth's magnetic field. The amount of solar wind is not constant due to changes in solar activity in each solar cycle, and hence the level of cosmic ray modulation varies with solar activity. In this context, we have investigated the variability and the relationship of cosmic ray intensity with solar, interplanetary, and geophysical parameters from January 1982 through December 2008. Simultaneous observations have been made to quantify the exact relationship between the cosmic ray intensity and those parameters during the solar maxima and minima, respectively. It is found that the stronger the interplanetary magnetic field, solar wind plasma velocity, and solar wind plasma temperature, the weaker the cosmic ray intensity. Hence, the lowest cosmic ray intensity has good correlations with simultaneous solar parameters, while the highest cosmic ray intensity does not. Our results show that higher solar activity is responsible for a higher geomagnetic effect and vice versa.

Advances in Space Research, 2001

Cosmic rays (CR) create the lower parts of~lanetary ionospheres. The observed CR spectrum can be distributed into the following five intervals: I (E = 3.10-10 H GeV/n), II (E = 3. l0 2-3.10 6 GeV/n), III (E = 30 MeV/n-3.102GeV/n), IV (E = 1-30 MeV/n) and V (E = 10 KeV/n-1 MeV/n), where E is the kinetic energy of the particles (Dorman, 1977; Velinov, 2000). Some methods exist for calculating ionization by relativistic particles in CR intervals I, II and III. For the high latitude and polar ionosphere, however, intervals III, IV and V are also significant since they contain solar cosmic ray and anomalous cosmic ray components. Formulas for the electron production rate q (cm3s-t) at height h in the planetary ionosphere as a result of penetration of energetic particles from intervals III, 1V and V are deduced in this paper. For this purpose the law of particle energy transformation by penetration through the ionosphere-atmosphere system is obtained. A model for the calculation of the cosmic ray spectrum on the basis of satellite measurements is created. This computed analytical model gives a practical possibility for investigation of experimental data from measurements of galactic cosmic rays and their anomalous component.

International Journal of Physical Sciences, 2019

In this work, monthly means of cosmic ray count rates from two mid latitude (Hermanus and Rome), and two higher latitude (Inuvik and Oulu) neutron monitors (NM) were employed and their variability was compared with geomagnetic stations that are in close proximity to the NMs. The data spans 1966 to 2008 and covers four solar cycles. The difference (CRdiff) between the mean count rate of all days and the mean of the five quietest days for each month was compared with the Dst-related disturbance (Hdiff) derived from the nearby geomagnetic stations. Zeroth-and First-correlation between the cosmic ray parameters and geomagnetic parameters was performed to ascertain statistical association and test for spurious association. The present results show that solar activity is generally strongly correlated (>0.75) with mean strength of GCR count rate and geomagnetic field during individual solar cycles. The correlation between mean strength of cosmic ray intensity and geomagnetic field strength is spurious and is basically moderated by the solar activity. The signature of convection driven disturbances at high latitude geomagnetic stations was evident during the declining phase of the solar cycles close to the solar minimums. The absence of this feature in the slow-time varying cosmic ray count rates in all stations and in the mid latitude geomagnetic stations suggests that the local geomagnetic disturbance do not play a significant role in modulating the cosmic ray flux.

The flux of incoming Cosmic Rays at the upper atmosphere is dependent on the Solar Wind, the Earth's magnetic field, and the energy of the cosmic rays. For cosmic radiation high energy particles originating outside a solar system. Cosmic rays are also responsible for the continuous production of a number of unstable isotopes in Earth's atmosphere. Cosmic rays can be used for validating magnetospheric field models during very severe storms. Cosmic rays are high-energy radiation, mainly originating outside the Solar System. Solar energetic particles and high-energy particles emitted by the sun. Measurements of the energy and arrival directions of the ultra-high-energy primary cosmic rays by the techniques of density sampling and fast timing of extensive air showers. When cosmic rays enter the Earth's atmosphere they collide with atoms and molecules, mainly oxygen and nitrogen. Gamma ray deriving from local supernovae could have affected cancer and mutation rates, and might be linked to decisive alterations in the Earth's climate.Solar Wind effects on the Cosmic-Ray Electrons from Solar Minimum to Solar Maximum.Cosmic Ray effects on a solar wind velocity gradually. Solar Wind consists of Magnetized Plasma flares and is linked to sunspots. Sunspot impact on the Space Weather and Earth's Environment.

Advances in Space Research, 2005

The galactic (GCRs) and anomalous (ACRs) cosmic rays form the lower parts of the planetary ionospheres. For this purpose analytical and numerical spectra for cosmic particles are necessary. The spectra of GCRs and ACRs observed in the Solar system are modulated by the Sun. Our knowledge of GCR modulation in the solar system was greatly enhanced thanks to the heliospheric missions, Voyager 1 and 2 that covered the outer Solar system up to $75 AU radial distance from the Sun. In this paper, a new model for the calculation of the GCR and ACR differential spectra D(E) on the basis of satellite and balloon measurements is created. This computed analytical model gives a practical possibility for investigation of experimental data from measurements of galactic cosmic rays and their anomalous component. The integral spectra D(>E) are computed and also obtained. The average radial gradient of GCR is accepted 4%/AU [F. Mcdonald, Z. Fujii, et al. The cosmic ray radial and latitudinal intensity gradient in the inner and outer heliosphere, in: Proceedings of 27th International Cosmic Ray Conference, Copernicus Gesellschaft, p. 3906, 2001]. The contribution of GCRs and ACRs to the ionization of the ionospheres of outer planets will be increased with increase of the planetary distances from the Sun.

Journal of Atmospheric and Solar-Terrestrial Physics, 2010

Long-term trends in the tropospheric cosmic ray induced ionization on the multi-millennial time scale are studied using the newly released paleomagnetic reconstruction models. Spatial and temporal variations of the tropospheric ionization has been computed using the CRAC:CRII model and applying the paleomagnetic CALS7k.2 reconstruction. It has been shown that long-term variations of the tropospheric ionization are not spatially homogeneous, and they are defined not only by solar (i.e., covariant with solar irradiance) changes but also by the geomagnetic field. The dominance of the two effects is geographically separated, which makes it possible to distinguish between direct and indirect solar-terrestrial climate effects. Possible climate applications are considered.

The proposed model generalizes the differential D(E) and integral D(>E) spectra of galactic and anomalous cosmic ray protons during the 11-year solar cycle. The model takes into account the CR modulation by the solar wind. The measurements with SIS and CRS spectrometers for anomalous component are examined with numerical solutions of the model equations. The radial gradient G0 of GCR is relatively small in the inner heliosphere. After a transition region between 10 and 20 AU, G0 increases to a much larger value that remains constant between ~25 and 80 AU. This shows that the contribution of GCRs and ACRs to the ionization of the atmospheres of outer planets Uranus, Neptune and Pluto will be increased drastically. We suppose that the galactic and anomalous cosmic rays (modulated by the solar wind) are important factors in the solar-terrestrial relationships. They influence strongly on the ionization state of the system ionosphere-thermosphere-middle atmospheres. The cosmic rays tr...

2005

The proposed model generalizes the differential D(E) and integral D(>E) spectra of galactic and anomalous cosmic ray protons during the 11-year solar cycle. The model takes into account the CR modulation by the solar wind. The measurements with SIS and CRS spectrometers for anomalous component are examined with numerical solutions of the model equations. The radial gradient G 0 of GCR is relatively small in the inner heliosphere. After a transition region between 10 and 20 AU, G 0 increases to a much larger value that remains constant between ~25 and 80 AU. This shows that the contribution of GCRs and ACRs to the ionization of the atmospheres of outer planets Uranus, Neptune and Pluto will be increased drastically. We suppose that the galactic and anomalous cosmic rays (modulated by the solar wind) are important factors in the solar-terrestrial relationships. They influence strongly on the ionization state of the system ionosphere-thermosphere-middle atmospheres. The cosmic rays transfer the solar variability, even in the lower atmosphere-troposphere and they influence on the weather and on the electrical parameters of the atmosphere (electrical conductivities, frequency of lightning, etc.).

Advances in Space Research, 2005

Solar energetic particles (SEPs) constitute a distinct population of energetic charged particles, which can be often observed in the near Earth space. SEP penetration into the EarthÕs magnetosphere is a complicated process depending on particle magnetic rigidity and geomagnetic field structure. Particles in the several MeV energy range can only access to periphery of the magnetosphere and the polar cap regions, while the GeV particles can arrive at equatorial latitudes. Solar protons with energies higher than 100 MeV may be observed in the atmosphere above $30 km, and those with energies more than 1 GeV may be recorded even at the sea level. There are some observational evidences of SEP influence on atmospheric processes. Intruding into the atmosphere, SEPs affect middle atmosphere odd-nitrogen and ozone chemistry. Since spatial and temporal variations of SEP fluxes in the near Earth space are controlled by solar activity, SEPs may present an important link between solar activity and climate. The paper outlines dynamics of SEP fluxes in the near Earth space during the last decades. This can be useful for tracing relationship between SEPs and atmospheric processes.

Journal of Space Weather and Space Climate, 2013

A brief review of the study during COST Action ES0803 of effects due to cosmic rays (CR) and solar energetic particles (SEP) in the ionosphere and atmosphere is presented. Models CORIMIA (COsmic Ray Ionization Model for Ionosphere and Atmosphere) and application of CORSIKA (COsmic Ray SImulations for KAscade) code are considered. They are capable to compute the cosmic ray ionization profiles at a given location, time, solar and geomagnetic activity. Intercomparison of the models, as well as comparison with direct measurements of the atmospheric ionization, validates their applicability for the entire atmosphere and for the different levels of the solar activity. The effects of CR and SEP can be very strong locally in the polar cap regions, affecting the physical-chemical and electrical properties of the ionosphere and atmosphere. Contributions here were also made by the anomalous CR, whose ionization is significant at high geomagnetic latitudes (above 65°-70°). Several recent achievements and application of CR ionization models are briefly presented. This work is the output from the SG 1.1 of the COST ES0803 action (2008-2012) and the emphasis is given on the progress achieved by European scientists involved in this collaboration.