Three-Dimensional Cosmic-Ray Simulations: Heliographic Latitude and Current-Sheet Tilt

The theoretical analyses of the extensive air showers developing from the cosmic radiation has its origins in the work of Carlson and Oppenheimer (1937) and Bhabha and Heitler (1937), at a time when it was thought that such showers were initiated by electrons. The realization that protons and other nuclei were the primary particles led to a reformulation of the theory by Heitler and Janossy (1949), Messel and Green (1952) and others, in which the production of energetic pions and the three-dimensional development of air showers were accounted for. But as the soft (electromagnetic) component of the cosmic radiation is the most prominent feature of air showers at sea level, there has been a sustained interest in the theory of this component. Most of the more recent work, such as that by Butcher and Messel (1960) and Thielheim and Zöllner (1972) has relied on computer simulation; but this method has disadvantages in terms of accuracy and presentation of results, especially where a simultaneous analysis of the development of air showers in terms of several physical variables is required. This is so for instance when the time of arrival is one of the variables. Moyal (1956) played an important part in the analytical formulation of a stochastic theory of cosmic ray showers, with time as an explicit variable, and it is essentially this approach which will be adopted in the following. The actual distribution of arrival times is cosmic ray showers, for which results are obtained, is of current experimental interest (McDonald, Clay and Prescott (1977)).

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Numerical study of the reconnection process between magnetic cloud and heliospheric current sheet

Astronomy and Astrophysics ◽

10.1051/0004-6361/201832951 ◽

2018 ◽

Vol 619 ◽

pp. A82

Author(s):

Man Zhang ◽

Yu Fen Zhou ◽

Xue Shang Feng ◽

Bo Li ◽

Ming Xiong

Keyword(s):

Magnetic Reconnection ◽

Current Sheet ◽

Dynamic Process ◽

Large Scale ◽

Magnetic Cloud ◽

Numerical Study ◽

Three Dimensional ◽

Heliospheric Current Sheet ◽

Reconnection Process ◽

Magnetic Filed

In this paper, we have used a three-dimensional numerical magnetohydrodynamics model to study the reconnection process between magnetic cloud and heliospheric current sheet. Within a steady-state heliospheric model that gives a reasonable large-scale structure of the solar wind near solar minimum, we injected a spherical plasmoid to mimic a magnetic cloud. When the magnetic cloud moves to the heliospheric current sheet, the dynamic process causes the current sheet to become gradually thinner and the magnetic reconnection begin. The numerical simulation can reproduce the basic characteristics of the magnetic reconnection, such as the correlated/anticorrelated signatures in V and B passing a reconnection exhaust. Depending on the initial magnetic helicity of the cloud, magnetic reconnection occurs at points along the boundary of the two systems where antiparallel field lines are forced together. We find the magnetic filed and velocity in the MC have a effect on the reconnection rate, and the magnitude of velocity can also effect the beginning time of reconnection. These results are helpful in understanding and identifying the dynamic process occurring between the magnetic cloud and the heliospheric current sheet.

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The Effects of Three Dimensional Structures on Cosmic-Ray Propagation and Interstellar Emissions

10.22323/1.236.0517 ◽

2016 ◽

Author(s):

Gudlaugur Johannesson ◽

I. V. Moskalenko ◽

Elena Orlando ◽

Troy Porter ◽

Andy Strong

Keyword(s):

Three Dimensional ◽

Cosmic Ray

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Formation of Dawn-Dusk Asymmetry in Earth's Magnetotail Thin Current Sheet: A Three-Dimensional Particle-In-Cell Simulation

Journal of Geophysical Research Space Physics ◽

10.1002/2017ja025095 ◽

2018 ◽

Vol 123 (4) ◽

pp. 2801-2814 ◽

Cited By ~ 6

Author(s):

San Lu ◽

P. L. Pritchett ◽

V. Angelopoulos ◽

A. V. Artemyev

Keyword(s):

Current Sheet ◽

Three Dimensional ◽

Particle In Cell ◽

Thin Current Sheet ◽

Cell Simulation

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Three-Dimensional Structure of the Heliospheric Current Sheet

Astrophysics and Space Science Library - The Sun and the Heliosphere in Three Dimensions ◽

10.1007/978-94-009-4612-5_35 ◽

1986 ◽

pp. 287-293 ◽

Cited By ~ 1

Author(s):

Craig D. Fry ◽

S.-I. Akasofu

Keyword(s):

Current Sheet ◽

Three Dimensional ◽

Heliospheric Current Sheet ◽

Dimensional Structure ◽

Three Dimensional Structure

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3D turbulent reconnection driven current-sheet dynamics: solar applications

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311007484 ◽

2010 ◽

Vol 6 (S274) ◽

pp. 458-460

Author(s):

Lapo Bettarini ◽

Giovanni Lapenta

Keyword(s):

Current Sheet ◽

Characteristic Time ◽

Three Dimensional ◽

Reynolds Numbers ◽

Anomalous Effect ◽

Instability Modes ◽

Diffusive Dynamics ◽

Three Dimensional Configuration ◽

A Current ◽

Dimensional Picture

AbstractWe provide a complete three-dimensional picture of the reconnecting dynamics of a current-sheet. Recently, a two-dimensional non-steady reconnection dynamics has been proved to occur without the presence of any anomalous effect (Lapenta, 2008, Skender & Lapenta, 2010, Bettarini & Lapenta, 2010) but such a picture must be confirmed in a full three-dimensional configuration wherein all instability modes are allowed to drive the evolution of the system, i.e. to sustain a reconnection dynamics or to push the system along a different instability path. Here we propose a full-space analysis allowing us to determine the longitudinal and, possibly, the transversal modes driving the different current-sheet disruption regimes, the corresponding characteristic time-scales and to study system's instability space- parameter (plasma beta, Lundquist and Reynolds numbers, system's aspect ratio). The conditions leading to an explosive evolution rather then to a diffusive dynamics as well as the details of the reconnection inflow/outflow regime at the disruption phase are determined. Such system embedded in a solar-like environment and undergoing a non-steady reconnection evolution may determine the formation both of jets and waves influencing the dynamics and energetic of the upper layers and of characteristic down-flows as observed in the low solar atmosphere.

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