scholarly journals Energy spectra and pitch angle distributions of auroral electrons observed in active and quiet auroras.

1988 ◽  
Vol 40 (7) ◽  
pp. 871-886 ◽  
Author(s):  
Hisao YAMAGISHI ◽  
Hiroshi MIYAOKA ◽  
Masaki EJIRI ◽  
Eiichi SAGAWA ◽  
Nobuyuki KAYA ◽  
...  
Keyword(s):  
Pitch Angle ◽  
Energy Spectra ◽  
Auroral Electrons

scholarly journals Excitation And Ionization By Auroral Protons

1966 ◽  
Vol 19 (3) ◽  
pp. 309 ◽  
Keyword(s):  
Magnetic Field ◽  
Energy Range ◽  
Pitch Angle ◽  
Proton Energy ◽  
Ionization Rate ◽  
Energy Spectra ◽  
Proton Fluxes ◽  
Atmospheric Ionization ◽  
The Magnetic Field

Height distributions are presented for the atmospheric ionization rate and Balmer radiation resulting from precipitation of auroral protons. These results have been computed assuming proton fluxes with several different energy spectra and pitch-angle distributions about the magnetic field, the total proton energy range being restricted to 1-1000 keY.

Energy and pitch angle-dispersed auroral electrons suggesting a time-variable, inverted-V potential structure

1999 ◽  
Vol 104 (A10) ◽  
pp. 22613-22621 ◽  
Author(s):  
R. L. Arnoldy ◽  
K. A. Lynch ◽  
J. B. Austin ◽  
P. M. Kintner
Keyword(s):  
Pitch Angle ◽  
Time Variable ◽  
Auroral Electrons ◽  
Potential Structure

Pitch angle diffusion of low-energy auroral electrons

1973 ◽  
Vol 78 (10) ◽  
pp. 1608-1614 ◽  
Author(s):  
B. A. Whalen ◽  
I. B. McDiarmid
Keyword(s):  
Pitch Angle ◽  
Low Energy ◽  
Auroral Electrons

Pitch angle and energy distributions of auroral electrons measured by the ESRO 4 satellite

1979 ◽  
Vol 27 (1) ◽  
pp. 87-97 ◽  
Author(s):  
Lars Eliasson ◽  
Lars-Åke Holmgren ◽  
Kjell Rönnmark
Keyword(s):  
Pitch Angle ◽  
Energy Distributions ◽  
Auroral Electrons

N2 positive and N2+ band systems and the energy spectra of auroral electrons

1972 ◽  
Vol 20 (6) ◽  
pp. 905-917 ◽  
Author(s):  
D.E. Shemansky ◽  
T.M. Donahue ◽  
E.C. Zipf
Keyword(s):  
Energy Spectra ◽  
Auroral Electrons

Energy spectra and pitch angle distributions of storm-time and substorm injected protons

1973 ◽  
Vol 78 (22) ◽  
pp. 4739-4744 ◽  
Author(s):  
A. Konradi ◽  
D. J. Williams ◽  
T. A. Fritz
Keyword(s):  
Pitch Angle ◽  
Energy Spectra

ROCKET MEASUREMENTS IN PROTON AURORA

1967 ◽  
Vol 45 (10) ◽  
pp. 3247-3255 ◽  
Author(s):  
B. A. Whalen ◽  
I. B. McDiarmid ◽  
E. E. Budzinski
Keyword(s):  
Pitch Angle ◽  
Energy Spectra ◽  
Angular Distributions ◽  
Electron Spectra ◽  
Source Mechanisms ◽  
Electron Intensity ◽  
Proton Precipitation ◽  
Rocket Measurements ◽  
Short Time ◽  
Proton Aurora

Proton and electron intensities, energy spectra, and angular distributions derived from a recent rocket flight launched into a 40-rayleigh Hβ aurora are reported. High-intensity proton precipitation (~0.45 erg cm−2 s−1 for protons with energies above 30 keV) was detected throughout the flight above 100 km, whereas the electron intensity was above the limit of detectability for only a short time. The proton and electron spectra and angular distributions in the 20–60 keV energy range were found to be remarkably similar, with angular distributions being isotropic over the pitch-angle range 0–90°, and with e-folding energies of about 12 keV and 18 keV for protons and electrons respectively. The results are interpreted in terms of current magnetospheric models, and are shown to place certain restrictions on the source mechanisms.

scholarly journals Particle acceleration with anomalous pitch angle scattering in 3D separator reconnection

2020 ◽  
Vol 635 ◽  
pp. A63
Author(s):  
A. Borissov ◽  
T. Neukirch ◽  
E. P. Kontar ◽  
J. Threlfall ◽  
C. E. Parnell
Keyword(s):  
Particle Acceleration ◽  
Magnetic Reconnection ◽  
Test Particle ◽  
Pitch Angle ◽  
High Energy ◽  
Energy Spectra ◽  
Mhd Simulation ◽  
Mhd Simulations ◽  
Angle Scattering ◽  
Particle Orbits

Context. Understanding how the release of stored magnetic energy contributes to the generation of non-thermal high energy particles during solar flares is an important open problem in solar physics. There is a general consensus that magnetic reconnection plays a fundamental role in the energy release and conversion processes taking place during flares. A common approach for investigating how reconnection contributes to particle acceleration is to use test particle calculations in electromagnetic fields derived from numerical magnetohydrodynamic (MHD) simulations of reconnecting magnetic fields. These MHD simulations use anomalous resistivities that are orders of magnitude larger than the Spitzer resistivity that is based on Coulomb collisions. The processes leading to such an enhanced resistivity should also affect the test particles, for example, through pitch angle scattering. This study explores the effect of such a link between the level of resistivity and its impact on particle orbits and builds on a previous study using a 2D MHD simulation of magnetic reconnection. Aims. This paper aims to extend the previous investigation to a 3D magnetic reconnection configuration and to study the effect on test particle orbits. Methods. We carried out orbit calculations using a 3D MHD simulation of reconnection in a magnetic field with a magnetic separator. The orbit calculations use the relativistic guiding centre approximation but, crucially, they also include pitch angle scattering using stochastic differential equations. The effects of varying the resistivity and the models for pitch angle scattering on particle orbit trajectories, final positions, energy spectra, final pitch angle distribution, and orbit duration are all studied in detail. Results. Pitch angle scattering widens highly collimated beams of unscattered orbit trajectories, allowing orbits to access previously unaccessible field lines; this causes final positions to spread along other topological structures which could not be accessed without scattering. Scattered orbit energy spectra are found to be predominantly affected by the level of anomalous resistivity, with the pitch angle scattering model only playing a role in specific, isolated cases. This is in contrast to the study involving a 2D MHD simulation of magnetic reconnection, where pitch angle scattering had a more noticeable effect on the energy spectra. Pitch scattering effects are found to play a crucial role in determining the pitch angle and orbit duration distributions.

Sign in / Sign up

Export Citation Format

Share Document