G. P. Lyubimov

Local Radiation Belts of the Sun (Quasi-Stationary Coronal and Heliospheric Giant Traps for Solar Cosmic Rays)

The local radiation belts of the Sun are defined as giant quasi-stationary coronal and heliospheric traps for solar cosmic rays. These traps are formed by loop magnetic fields, both solar and interplanetary. Using observational data, some experimental examples of the local radiation belts of the Sun are considered. The hypotheses on the origin of energetic particles in the outer heliosphere and on the local radiation belts of the Sun are discussed.

Some features of solar cosmic ray penetration into the Earth’s magnetosphere

We compared fluxes of the 1–100 MeV solar energetic particles (SEP) measured in the interplanetary medium (ACE) and in the magnetosphere (Universitetsky-Tatiana, POES—in polar caps, and GOES-11—at geosynchronous orbit) during several SEP events of 2005–2006. Peak intensities of the SEP fluxes inside and outside the magnetosphere were compared for each event. It is shown that observed inside-outside difference depends mainly on direction of interplanetary magnetic field (IMF), on degree of the SEP anisotropy (pitch-angle distribution) in IMF, and on distance of the dayside magnetopause from the Earth.

Specific features of solar cosmic ray fluxes and geomagnetic conditions on December 5–18, 2006

Results of the analysis of specific features of solar activity, dynamics of solar cosmic ray fluxes, and state of the interplanetary medium are presented for the period December 5–18, 2006. The data analysis is based on new model concepts on coronal and interplanetary propagation of solar cosmic rays: partial capture into the magnetic field traps and oscillations at reflections from magnetic mirrors. Some new hypotheses about possible relations of the features of the interplanetary medium with processes in the Earth’s magnetosphere are put forward: the influence of the discrete interplanetary medium on processes in the Earth’s magnetosphere does exist always and, in this sense, it is a fundamental phenomenon; the discreteness of the inter-planetary medium can be one of the causes of geomagnetic substorms.

The reflection model for propagation of solar cosmic rays

The principles of constructing the model are considered in this paper, together with the issues of its components and physical algorithm. The main emphasis is placed on the cause-and-effect relationships between the structure and dynamics of the solar and interplanetary media and the motion of solar cosmic ray particles. The specific features of the initial phase of motion of the particles after their acceleration in a solar flare are considered, as well as the subsequent phase of further particle propagation in the solar corona, and the phase of motion in the heliosphere. The processes of transport of charged particles in flare plasma ejections are considered in detail.

Model of the solar cosmic ray burst on March 19, 1990

The causes of oscillation of the solar cosmic ray flux and alternating-sign anisotropy with a period of three hours to two minutes in March 1990 measured on the Granat satellite are analyzed in this paper. It is shown that they are caused by the motion of solar cosmic ray protons with the energy 1–100 MeV in loop structures of solar magnetic fields of the chromosphere and the corona transferred into the interplanetary medium by plasma of the solar wind. A model description of the observation data is presented.

A Series of Proton Flares in July 1985 from Observations by the Prognoz-10 Satellite and Vega-1, 2 Spacecraft

The enhancements of solar protons with an energy of more than 30 MeV, originating from flares in one active region and observed simultaneously aboard three spacecraft Vega-1, 2 and Prognoz-10 in July 1985, are analyzed and approximated in this work by using the reflection model [2]. The numerical values of several physical parameters (the parameters of distribution of solar cosmic ray (SCR) particles inside heliosphere traps, the coefficients of trap transparency) that are not observed by direct measurements are estimated.

Solar Flare Peculiarities: A Hypothesis for a New Phenomenological Model

An intensity time-profile of the hard X-ray emission in two cores of a small impulsive solar flare is analyzed. The emission in the cores proved to evolve in the opposite phases. The phases of growth and decay are also shown to be modulated by the slower oscillatory variations. It is suggested that acceleration processes may be oscillating and a collapsing acceleration process may occur above and below the photosphere.

Motion and Transport of Solar Cosmic Rays in Heliospheric Traps: The Event on January 28–31, 2001

The results of studying the enhancement of solar cosmic ray fluxes on January 28–31, 2001 in a wide energy range are presented using the ACE spacecraft data. A comparative analysis of temporal variations of the fluxes of charged particles and of the interplanetary medium parameters (interplanetary magnetic field and solar wind) has been performed on the basis of the “reflection” model of motion, accumulation, and modulation of cosmic rays. It is shown that a magnetic trap for solar cosmic rays was created by a plasma stream and flare ejection from an active region in the western part of the solar disk. Particles of low energies (<10 MeV) were captured inside the trap; the dispersion of distribution of particles with different energies inside the trap being determined by its complicated magnetic structure. The power-low dependence of the time of maximum for the flux of particles on their energy is found, and softer energy spectrum inside the trap is explained.

“Meander”-like and “slit”-like variations in the flux of solar cosmic rays

Results of studying the origin of “meander”-like and “slit”-like variations in fluxes of solar cosmic rays (SCR) are presented as exemplified by the events that occurred on March 19, 1990 and December 14–15, 2006. Experimental data that were obtained by the GRANAT, ACE, Wind, STEREO-A, and STEREO-B spasecrafts are used. The analysis is based on the data of observations of dynamic structures in the solar atmosphere and their continuation in the heliosphere, as well as on an empirical “reflection” model of the movement, accumulation, and modulation of cosmic rays. A structural source of these variations on the Sun is discussed, which is shaped as discrete magnetic plasma loops and arches located between active regions. Such structures in the form of magnetic-plasma tubes transferred from the chromosphere and corona and filled with SCR rotate together with the Sun and, when crossing the detector location region, cause space-time variations in meander-like and slit-like variations in SCR.

Modulation of galactic cosmic ray intensities by coronal mass ejections into interplanetary space

The data on the measurements of the intensities of galactic cosmic rays with proton energies greater than 30 MeV are compared with the data on the solar wind and interplanetary magnetic field measured on board the Vega-1 and Vega-2 automated interplanetary stations. Modulation structures with characteristic shapes and durations, namely quasi-symmetric (“bays”) short-term Forbush decreases of intensity, are revealed. It is shown that these Forbush decreases were recorded due to the stations flying through coronal mass-ejection regions.