Equatorial Pitch Angle Research Articles

ELFIN‐GPS Comparison of Energetic Electron Fluxes: Modeling Low‐Altitude Electron Flux Mapping to the Equatorial Magnetosphere

AbstractNear‐equatorial measurements of energetic electron fluxes, in combination with numerical simulation, are widely used for monitoring of the radiation belt dynamics. However, the long orbital periods of near‐equatorial spacecraft constrain the cadence of observations to once per several hours or greater, that is, much longer than the mesoscale injections and rapid local acceleration and losses of energetic electrons of interest. An alternative approach for radiation belt monitoring is to use measurements of low‐altitude spacecraft, which cover, once per hour or faster, the latitudinal range of the entire radiation belt within a few minutes. Such an approach requires, however, a procedure for mapping the flux from low equatorial pitch angles (near the loss cone) as measured at low altitude, to high equatorial pitch angles (far from the loss cone), as necessitated by equatorial flux models. Here we do this using the high energy resolution ELFIN measurements of energetic electrons. Combining those with GPS measurements we develop a model for the electron anisotropy coefficient, , that describes electron flux dependence on equatorial pitch‐angle, , . We then validate this model by comparing its equatorial predictions from ELFIN with in‐situ near‐equatorial measurements from Arase (ERG) in the outer radiation belt.

Influence of Initial Proton Energy on the Nonlinear Interactions Between Ring Current Protons and He+ Band EMIC Waves

AbstractThe energy of ring current protons is believed to influence the pitch angle scattering due to electromagnetic ion cyclotron (EMIC) waves and is typically analyzed using quasi‐linear theory. However, nonlinear behavior becomes significant as the wave amplitude intensifies. In this study, we aim to explore how the nonlinear behavior depends on the initial proton energy under various background plasma density conditions. The frequency of EMIC waves is 0.96ΩHe (where ΩHe is the gyrofrequency of He+ at the equator). It is found that the higher energy protons with nonlinear phase trapping experience more resonances, causing these trapped protons to move away from the loss cone more quickly compared to lower energy protons. However, the proportion of phase‐trapped protons significantly decreases as the initial proton energy increases. This declining trend is more pronounced for a background plasma condition in the plasmapause than within the plasmasphere. The number of phase‐trapped protons goes to zero as initial proton energy increases to above approximately 60 keV. Additionally, nonlinear phase bunching is more pronounced for lower energy protons (e.g., below 60 keV) compared to higher energy protons. As a result, both nonlinear phase trapping and phase bunching contribute to larger standard deviations in the net changes of equatorial pitch angle (Δαeq), suggesting a larger pitch agnel diffusion coefficient compared to the prediction of quasi‐linear theory.

Separation of Electron Flux in Pitch Angle Distribution During the Drift Echo Event and Shabansky Orbits Effect

AbstractThe Shabansky orbit effect can exert a significant influence on the dynamics of particle motion. However, the north‐south asymmetry of the Shabansky orbits has received relatively little attention in previous research. This study investigates this asymmetry to elucidate the recently observed phenomenon of flux separation in the pitch angle distribution during drift echo events. The asymmetry in Shabansky orbits between the northern and southern hemispheres leads to two distinct drift periods for particles with specific equatorial pitch angles, resulting in the flux separation. To quantify this phenomenon, we develop a mathematical model for the magnetic field, enabling the generation of asymmetrical Shabansky orbits. The calculated drift periods for particles with different equatorial pitch angles corresponds with the characteristics of flux separation, providing evidence to support our hypothesis that the north‐south asymmetry of Shabansky orbits is responsible for flux separation.

A New Model of Electron Pitch Angle Distributions and Loss Timescales in the Earth's Radiation Belts

AbstractAs the number of satellites on orbit grows it is increasingly important to understand their operating environment. Physics‐based models can simulate the behavior of the Earth's radiation belts by solving a Fokker‐Planck equation. Three‐dimensional models use diffusion coefficients to represent the interactions between electromagnetic waves and the electrons. One‐dimensional radial diffusion models neglect the effects of energy diffusion and represent the losses due to the waves with a loss timescale. Both approaches may use pitch angle distributions (PADs) to create boundary conditions, to map observations from low to high equatorial pitch angles and to calculate phase‐space density from observations. We present a comprehensive set of consistent PADs and loss timescales for 2 ≤ L* ≤ 7, 100 keV ≤ E ≤ 5 MeV and all levels of geomagnetic activity determined by the Kp index. These are calculated from drift‐averaged diffusion coefficients that represent all the VLF waves that typically interact with radiation belt electrons and show good agreement with data. The contribution of individual waves is demonstrated; magnetosonic waves have little effect on loss timescales when lightning‐generated whistlers are present, and chorus waves contribute to loss even in low levels of geomagnetic activity. The PADs vary in shape depending on the dominant waves. When chorus is dominant the distributions have little activity dependence, unlike the corresponding loss timescales. Distributions peaked near 90° are formed by plasmaspheric hiss for L* ≤ 3 and E < 1 MeV, and by EMIC waves for L* > 3 and E > 1 MeV. When hiss dominates, increasing activity broadens the distribution but when EMIC waves dominate increasing activity narrows the distribution.

A method of reconstruction of anisotropic fluxes of geomagnetically trapped particles from in-flight measurements of high precision

High anisotropy of geomagnetically trapped particles’ fluxes requires utilization of a complex methodology for their reconstruction from in-flight measurements. For precise position-sensitive instruments operating in the event-by-event mode, a standard approach is the one originally developed for the SAMPEX/MAST experiment. It consists in calculation of the instrument’s effective areas averaged over gyro-phase angle as a function of pitch angle of detected particles for detector’s different orientations relative to the geomagnetic field vector. This orientation normally changes as the instrument moves in space. Moreover, some space vehicles bearing a measuring instrument may and do change their orientation during flight by rotation of the instrument or as a whole. Each possible orientation needs an independent calculation of effective areas for each possible pitch angle, which is usually done by means of Monte-Carlo simulation. Therefore, especially for sophisticated devices, the calculation of an accurate and representative response function (consisting of a set of effective areas) may involve a vast amount of computation.In this paper, we propose a simplified approach, which is based on the assumption that for an anisotropic flux, the angular sphere the particles come to the detector from can be split into solid angle domains, within which the flux can be treated as isotropic. This allows one to use much easier computed geometrical factor or acceptance of the instrument as the proportionality factor. This method suggests that it can be calculated with respect to registration of the particles from these domains (we call it partial acceptance). The main advantage of the presented method is that the whole set of partial acceptances for each instrument orientation relative to the geomagnetic field vector and for all available values of (equatorial) pitch-angle for this orientation can be obtained from one simulation sample (for the given energy) of isotropic flux.

Bounce Resonance Between Energetic Electrons and Magnetosonic Waves: A Parametric Study

AbstractMagnetosonic (MS) waves are electromagnetic emissions from a few to 100 Hz primarily confined near the magnetic equator both inside and outside the plasmasphere. Previous studies proved that MS waves can transport equatorially mirroring electrons from an equatorial pitch angle of 90° down to lower values by bounce resonance. However, the dependence of the bounce resonance effect on wave or background plasma parameters is still unclear. Here, we applied a test particle simulation to investigate electron transport coefficients, including diffusion and advection coefficients in energy and pitch angle, due to bounce resonance with MS waves. We investigate five wave field parameters, including wave frequency width, wave center frequency, latitudinal distribution width, wave normal angle root‐mean‐square of wave magnetic amplitude, and two background parameters, L‐shell value and plasma density. We find different transport coefficient peaks resulting from different bounce resonance harmonics. Higher‐order harmonic resonances exist, but the effect of fundamental resonance is much stronger. As the wave center frequency increases, higher‐order harmonics start to dominate. With wave frequency width increasing, the energy range of effective bounce resonance broadens, but the effect itself weakens. The bounce resonance effect will increase when we decrease the wave normal angle, or increase the wave amplitude, latitudinal distribution width, L‐shell value, and plasma density. The parametric study will advance our understanding of the favorable conditions of bounce resonance.

Cutoff Rigidities, Galactic Cosmic Ray Flux, and Heavy Ion Detections at Jupiter

AbstractA map of vertical cutoff rigidities has been calculated for galactic cosmic ray (GCR) entry into the atmosphere of Jupiter at the 1 bar pressure radius (1 RJ = 71,492 km) using the JRM33 comprehensive model of Jupiter's magnetic field (based on 32 close flybys of Jupiter by the Juno satellite) along with a particle trajectory code (Geomagnetic Cutoff Rigidity Computer Program). The map was combined with measurements of the GCR proton flux at Earth, from the BESS‐Polar ii campaign, to calculate a corresponding proton flux map at Jupiter. Additional cutoff rigidity maps were calculated for 1,000 km above the 1 bar level, and for 1.41 RJ. Furthermore, detections of heavy particles from Juno's Stellar Reference Unit were analyzed for their cutoff rigidities in multiple directions. Cutoff rigidities of 3.5–7.5 GV were found for five of the detections furthest out making them possible GCR candidates. The majority of points, located below 1.6 RJ are not likely to be GCR. Assuming instead that they are trapped particles we have calculated upper and lower limits on their equatorial pitch angles, resulting in a range from 10.1° to 27.1°, which can help constraining Jupiter's energetic radiation.

Simulation study on “Wisp” electron spectra generated by NWC very low frequency transmitter signals

Very low frequency (VLF) signals emitted by worldwide spread ground-based man-made transmitters mainly propagate in Earth-ionospheric waveguides and are used for submarine communication. A portion of these signals penetrate the ionosphere and leak into the magnetosphere when the ionospheric electron density decreases on the nightside due to the attenuated sunlight. The VLF transmitter signals in the magnetosphere can scatter electrons with energy of 100 Kev in the inner radiation belt into the drift loss cone through cyclotron resonance. This is an important loss mechanism for electrons in the inner radiation belt and plays an important role in transferring energy and mass from magnetosphere to ionosphere. Electrons scattered by transmitter signals exhibit a “wisp” characteristic in <i>L</i>-<i>E</i><sub><i>k</i></sub> spectrum, satisfying the first-order cyclotron resonance relationship between the electrons and the transmitter signals. The “wisp” spectrum can be clearly observed by low earth orbit satellites, presenting opportunities to study wave-particle interactions in near-Earth space. In this study, using the drift-diffusion-source model, we reproduce the “wisp” spectrum formed by scattering effects of NWC transmitter signals observed by DEMETER satellite on March 19, 2009. Our simulation results suggest that the equatorial pitch angle of electrons, observed by DEMETER, varies with the longitude, resulting in distinctions in the observed “wisp” spectrum along different longitudes. Specifically, as the satellite approaches South Atlantic Anomaly (SAA) region, both the energy range and flux level of the observed “wisp” spectrum gradually increase. When the previously studied wave normal angle model (with a central wave normal angle of 60°) and the background electron density model are used, the energy range of the simulated “wisp” spectra is higher than the observed value. Adjusting the central wave normal angle to 40° or increasing the background density by a factor of 1.3, the simulated results accord well with the observations. Our results elucidate the scattering effect of NWC transmitter signals on electrons in the radiation belt, and emphasize the importance of analyzing the formation of “wisp” spectrum for understanding wave-particle interactions in near-earth space. Additionally, the drift-diffusion-source model can be used to study wave-particle interactions in the inner radiation belt, providing an important basis for developing radiation belt remediation technology.

The Response of Electron Pitch Angle Distributions to the Upper Limit on Stably Trapped Particles

AbstractWe use Van Allen Probes electron data during 70 geomagnetic storms to examine the response of equatorial pitch angle distributions (PADs) at L* = 4.0–4.5 to a theoretical upper limit on stably trapped particle fluxes. Of the energies examined, 54 and 108 keV electron PADs isotropize to a previously assumed level within 6 hr of reaching the limit, near‐identically across all 70 storms, consistent with rapid pitch angle scattering due to chorus wave interactions. In around 30% of events, 54 keV electrons completely exceed the KP limit, before being quickly subdued. 470 and 749 keV PADs show clear indications of an upper limit, though less aligned with the calculated limit used here. The consistency of an absolute upper limit shown across all events demonstrates the importance of this phenomena in both the limiting effect on electron flux and consistently influencing electron PAD evolution during geomagnetic storms. These results also highlight the need for further investigation, particularly related to the limiting of higher energy electrons.

Quantifying the Absorption Loss of Radiation Belt Energetic Particles by Saturn's Inner Moons

AbstractSaturn owns various moons embedded in the magnetosphere, which results in the absorption loss of energetic particles in Saturn's radiation belts when they encounter the body of moons. In the present study, we perform a quantitative analysis of radiation belt energetic electron and proton lifetimes due to the absorption loss by five of inner moons of Saturn (Mimas, Enceladus, Tethys, Dione, and Rhea). Our results show that the resultant averaged lifetimes of energetic particles generally range from ∼0.01 days to infinity, depending strongly on particle energy, equatorial pitch angle, and moon orbit. The averaged lifetimes of energetic electrons increase with increasing electron energy at energies of <1 MeV and peak at the resonance energy, at which the electron drift velocities approach the Kepler velocities of moons. For >1 MeV electrons, the corresponding electron lifetimes decrease as electron energy increases. The averaged lifetimes of protons decrease monotonically with increasing equatorial pitch angles and kinetic energies. We find that the absorption loss by Tethys is the strongest, with the corresponding electron lifetimes shorter than 1 day and the corresponding proton lifetimes shorter than 10 days. The moon absorption effects due to Mimas are the weakest. Our results of energetic particle lifetimes due to the absorption loss by Saturn's moons can be incorporated into future modeling efforts of the radiation belt particle dynamics at Saturn.

Comparison of radiation belt electron fluxes simultaneously measured with PROBA-V/EPT and RBSP/MagEIS instruments

Abstract. Relativistic radiation belt electron observations from the Energetic Particle Telescope (EPT) on board the PROBA-V (Project for On-Board Autonomy and Vegetation) satellite are compared to those performed by the Magnetic Electron Ion Spectrometer (MagEIS) on board the Van Allen Probes formerly known as the Radiation Belt Storm Probes (RBSP). Despite their very different orbits, both instruments are able to measure fluxes of electrons trapped on a given magnetic shell. In the outer belt, the comparison of high- and low-altitude fluxes is performed during the first 3 months of 2014, featuring the most intense storms of the year. In the inner belt, measurements from the two instruments are compared only at conjunction, when the satellites are physically close to each other. Due to the low number of conjunctions, the whole period of mutual operation of both instruments is used (i.e., May 2013–October 2019). The comparisons show that flux variations appear simultaneously on both spacecraft, but the fluxes observed by the EPT are almost always lower than for MagEIS, as expected from their different orbits. In addition, this difference in flux intensity increases with electron energy. During geomagnetic storms, it is also shown that dropout events (i.e., sudden depletion of electrons) in the outer belt are more pronounced at low altitudes than near the geomagnetic Equator. The effect of the equatorial pitch angle value of electrons is investigated in the outer belt. Despite the difference in flux intensity observed by the two instruments, especially at high energies, a linear relationship with a linear correlation higher than 0.7 was found. The correlation is at its maximum when low-pitch-angle electrons near the Equator are considered.

Electron Lifetimes Measured at LEO: Comparison With RBSP Estimates and Pitch Angle Resolved Lifetimes

AbstractElectron lifetimes are important for understanding the dominant loss processes of radiation belt electrons to the atmosphere and for accurate radiation belt modeling. We estimate electron lifetimes from the precipitating population measured in Low Earth Orbit (LEO) from the Polar Orbiting Environmental Satellites (POES). We compare our estimates to previous estimates from the Radiation Belt Storm Probes (RBSP) by Claudepierre et al. (2020b, https://doi.org/10.1029/2019GL086053). We also present the first complete pitch angle resolved lifetimes in the radiation belts. Quasi‐linear theory predicts the pitch angle distribution decays uniformly, therefore if steady‐state decay is realized, POES and RBSP should measure similar lifetimes. Lifetime estimates from LEO are shown to be in good agreement with those from Van Allen Probes in the outer belt and pitch angle resolved lifetimes indicate that steady‐state decay is realized. However, a systematic slight overestimation of the POES lifetimes reveal that the POES instruments may suffer from bremsstrahlung contamination. At L = 2–3, no decay intervals were identified in the POES electron fluxes and the near loss cone RBSP electron fluxes. We show that at these L‐shells, where lifetimes are long, there is an apparent decoupling of the perpendicular and parallel flux. Large pitch angle anisotropy and processes that affect low pitch angle electrons are two explanations for this apparent decoupling. Electron lifetime models that use pitch angle independent lifetimes, derived from the equatorially mirroring electron flux, likely underestimate the amount of precipitating flux and may not capture the dynamics of low equatorial pitch angle electrons at L < 3.

Interaction of Relativistic Electrons with Packets of the Electromagnetic Ion Cyclotron Waves of Finite Length and Low Amplitude

Interaction of relativistic electrons with packets of the electromagnetic ion cyclotron waves of finite length and low amplitude in the Earth’s radiation belts is analyzed. The variance of the equatorial pitch angle of electrons for wave packets located near the Earth’s geomagnetic equator is estimated analytically within the linear approximation. The analytical estimates agree with the results of numerical test-particle simulation. It is demonstrated that reduction in the packet length extends the interaction range to lower energies beyond the range of resonant energies. Such an interaction can result in precipitation of electrons with energies on the order of several hundred kiloelectronvolts into the ionosphere.

Field‐Line Curvature Scattering at the Outer Boundary of the Proton Radiation Belt

AbstractA model balancing diffusive field‐line curvature (FLC) scattering loss with other local source, loss, and transport processes is used to compute the L‐shell location of the proton radiation belt outer boundary, where intensity falls below observable levels. The FLC scattering rate increases with increasing L and proton energy, decreasing equatorial pitch angle, and increasing geomagnetic activity, as determined with the Kp‐dependent T89 external magnetic field combined with a dipole internal field. Simulated proton intensity near the outer boundary is compared to measurements from both the low‐altitude SAMPEX satellite and the high‐altitude Van Allen Probes satellites, with correction for instrumental biases caused by field‐of‐view, energy range, and the east‐west effect. Good agreement between observations and simulations is obtained for average boundary locations, time‐dependent variations caused by magnetic storms, and average equatorial pitch‐angle distributions.

Proton Equatorial Pitch Angle Distributions in Jupiter's Inner Magnetosphere

AbstractWe use data from the plasma and energetic particle instruments on the Juno spacecraft, JADE and JEDI, to study the equatorial pitch angle distributions of energetic protons within Jupiter's inner magnetosphere during Juno's prime mission from 2016 to 2021. Averaging over all observations made by Juno within M‐shell bins between M = 6 and M = 30, we find protons at energies between 10 and 50 keV are predominantly field‐aligned at all M‐shells. In contrast, those at energies above 200 keV transition from being predominantly field‐aligned at M = 20 to having pancake‐like distributions at M < 10. We find the observed distributions are consistent either with charge exchange of protons with neutral toroidal clouds, or with adiabatic acceleration of protons originating from Jupiter that are transported inward from the middle magnetosphere.

Precipitation Rates of Electrons Interacting With Lower‐Band Chorus Emissions in the Inner Magnetosphere

AbstractElectrons trapped in the Earth's magnetic field can be scattered by whistler mode chorus emissions and precipitate into the Earth's upper atmosphere. Whistler mode chorus waves propagating in the Earth's inner magnetic field are usually observed with oblique wave normal angles (WNAs). In this study, we apply 12 chorus wave models with four various WNA sets (the maximum WNA are 0°, 20°, 60°, and 90% of resonance cone angles) and three wave amplitude sets (the maximum wave magnetic fields are 2.1 nT, 307 pT, and 49.4 pT) at L = 4.5. We use test‐particle simulations to trace electrons interacting with the waves and create Green's function sets for electrons initially at kinetic energies (K) 10–6,000 keV and equatorial pitch angles (α) 5°–89°. The simulation results show that in the 2.1 nT cases, the very oblique chorus waves contribute to more electron precipitation than the other three chorus wave models, especially at energies 50–100 keV. Checking the highest initial equatorial pitch angle of the precipitated electrons, we find that the very oblique chorus waves can precipitate electrons with α > 45°. In contrast, the other chorus waves can only precipitate electrons with α < 30°. Furthermore, the precipitation rates reveal that the anomalous trapping effect, which moves low equatorial pitch angle electrons away from the loss cone, in the oblique cases is much weaker than in the parallel case, resulting in higher precipitation rates. Finally, we derive the pitch angle scattering rates and verify the precipitation by nth cyclotron resonances with oblique chorus.

Search for Electron Bursts in the Inner Van Allen Belts with the CSES and NOAA POES Satellites

Earthquake monitoring plays a key role in human life protection, especially in highly populated areas of the Earth. First indications have been found in SAMPEX and NOAA satellite data that particle fluxes of trapped electrons in the Van Allen belts can be correlated to seismic activity on the ground. Within the framework of the CSES mission, a systematic analysis of the electron flux, within the invariant phase space in the L-shell and equatorial pitch angle, has started with the goal to identify short-term variations of the flux (particle bursts) in conjunction with seismic activity. This analysis is based on the statistical evaluation of the flux measurements and built to be potentially implemented in an online monitoring system. The first milestone in that direction has been achieved, providing a stable background estimation. With the injection of artificial signals, the efficiency of the method was evaluated and found to be better than 95% for isolated (one per day) and short (∼3 min) signals with a significance ≥ 5σ above the background. The developed method is set up in a manner to be easily applicable to data from different instruments and satellites. This article presents the studied datasets of the low-energy HEPP instrument onboard the CSES-01 satellite and the electron telescopes of the MEPED detector onboard the NOAA POES-19 satellite, introduces the method for the background estimation, and discusses the first correlation studies of particle bursts with geomagnetic indices obtained within this framework.

Pitch Angle Isotropy of Relativistic Electron Microbursts as Observed by SAMPEX/HILT: Statistical and Storm‐Time Properties

AbstractObservations of relativistic electron precipitation events from Earth's inner magnetosphere to the upper atmosphere provide essential information about the source/loss processes and dynamics of Earth's radiation belts. Equatorial electron pitch angle isotropy can be an indicator of electron precipitation into the atmosphere, with isotropic populations resulting in a full bounce loss cone (BLC) and anisotropic populations resulting in an emptier BLC. Here we study electron microbursts, which are ˜100 millisecond duration streams of relativistic electrons thought to be scattered into the BLC by particle‐wave scattering. By measuring the ratios of >1 MeV electron flux across different detector rows in the Heavy Ion Large Telescope (HILT) instrument onboard the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX) satellite, we quantify the pitch angle isotropy of an electron population. Applying this calculation to microburst events, we have determined the dependence of microburst pitch angle distributions on burst magnitude, magnetic local time (MLT), L‐Shell, and storm phase. We found that high flux magnitude microbursts are typically highly isotropic, while lower flux magnitude microbursts have varying degrees of anisotropy. Furthermore, microbursts are most isotropic as compared to the background population in the afternoon/evening sector as well as initial and main phases of geomagnetic storms. These results have important implications for microburst scattering mechanisms as well as quantification of precipitation driven by this process.

Scattering of energetic electrons through nonlinear cyclotron resonance with coherent whistler-mode hiss emissions

Recent observations have revealed that plasmaspheric hiss consists of many discrete waves called “hiss elements.” However, the interaction of energetic electrons (10 keV to several MeV) with the plasmaspheric hiss has only been simulated by the quasilinear (QL) diffusion theory, which does not take the fine wave structure into account. The QL theory cannot address nonlinear particle motions determined by the inhomogeneity factor, which influences the scattering of electrons in pitch angle and energy. This study aims to identify differences between the nonlinear wave–particle interaction and QL theory for plasmaspheric hiss emissions. We conduct test particle simulations to demonstrate the nonlinear interactions between hiss waves and electrons. The nonlinear theory is used to model hiss elements consisting of discrete frequencies and continuous phases. Unlike the other theories, the frequency and amplitude variations in time of the hiss packet are taken into account. Frequencies of the packets are determined to satisfy the separability criterion; when the criterion is met, resonance overlapping is absent, and the electrons can generate each wave element independently. The realistic simulation model of hiss waves reproduces the scattering of electrons by both first- and second-order resonances. We also evaluate the efficiency of electron scattering by calculating nonlinear diffusion coefficients. The diffusion coefficient of equatorial pitch angle is of the same order of magnitude as those calculated by the QL diffusion theory, while we find the effective acceleration of resonant electrons by successive nonlinear trapping, which is not evaluated by the QL theory.

Modeling the Effects of Drift Orbit Bifurcation on Radiation Belt Electrons

AbstractDrift orbit bifurcation (DOB) has been suggested to play a major role in the loss and transport of radiation belt electrons since it violates the second adiabatic invariants of particles and makes the third invariant undefined. Results from our guiding‐center test particle simulations using the Tsyganenko‐1989c magnetic field model show that the DOB could affect a broad region of the outer radiation belt, which can penetrate inside the geosynchronous orbit at Kp ≥ 3, and its effects are more significant further away from the Earth, at a higher Kp and for higher electron energies. Specifically, the short‐term simulation results after one electron drift show both traditional and nontraditional DOB transport of electrons, with the nontraditional DOB, caused by a third minimum of the magnetic field strength near the equator, reported here for the first time. Moreover, our results show large ballistic jumps in the second invariant and radial distance for electrons at high equatorial pitch angles after one drift. In addition, long‐term DOB transport coefficients of electrons over many drifts are calculated based on our simulation results. We find that the pitch angle and radial diffusion coefficients of electrons due to DOB could be comparable to or even larger than those caused by electron interactions with chorus and Ultra‐Low‐Frequency waves, respectively. In sum, our results demonstrate that DOB could cause effective loss and transport of radiation belt electrons even in the absence of waves.