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Khotyaintsev, Yuri V.ORCID iD iconorcid.org/0000-0001-5550-3113
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Publications (10 of 298) Show all publications
Rojo, M., Persson, M., Sauvaud, J.-a. -., Aizawa, S., Nicolaou, G., Penou, E., . . . Murakami, G. (2024). Electron moments derived from the Mercury Electron Analyzer during the cruise phase of BepiColombo. Astronomy and Astrophysics, 683, Article ID A99.
Open this publication in new window or tab >>Electron moments derived from the Mercury Electron Analyzer during the cruise phase of BepiColombo
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2024 (English)In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 683, article id A99Article in journal (Refereed) Published
Abstract [en]

Aims. We derive electron density and temperature from observations obtained by the Mercury Electron Analyzer on board Mio during the cruise phase of BepiColombo while the spacecraft is in a stacked configuration. Methods. In order to remove the secondary electron emission contribution, we first fit the core electron population of the solar wind with a Maxwellian distribution. We then subtract the resulting distribution from the complete electron spectrum, and suppress the residual count rates observed at low energies. Hence, our corrected count rates consist of the sum of the fitted Maxwellian core electron population with a contribution at higher energies. We finally estimate the electron density and temperature from the corrected count rates using a classical integration method. We illustrate the results of our derivation for two case studies, including the second Venus flyby of BepiColombo when the Solar Orbiter spacecraft was located nearby, and for a statistical study using observations obtained to date for distances to the Sun ranging from 0.3 to 0.9 AU. Results. When compared either to measurements of Solar Orbiter or to measurements obtained by HELIOS and Parker Solar Probe, our method leads to a good estimation of the electron density and temperature. Hence, despite the strong limitations arising from the stacked configuration of BepiColombo during its cruise phase, we illustrate how we can retrieve reasonable estimates for the electron density and temperature for timescales from days down to several seconds.

Place, publisher, year, edition, pages
EDP Sciences, 2024
Keywords
plasmas, instrumentation: detectors, methods: data analysis
National Category
Astronomy, Astrophysics and Cosmology Fusion, Plasma and Space Physics
Identifiers
urn:nbn:se:uu:diva-533313 (URN)10.1051/0004-6361/202347843 (DOI)001182147100002 ()
Funder
Swedish National Space Board
Available from: 2024-06-26 Created: 2024-06-26 Last updated: 2024-06-26Bibliographically approved
Graham, D. B., Khotyaintsev, Y. V., Dimmock, A. P., Lalti, A., Boldu, J. J., Tigik, S. F. & Fuselier, S. A. (2024). Ion Dynamics Across a Low Mach Number Bow Shock. Journal of Geophysical Research - Space Physics, 129(4), Article ID e2023JA032296.
Open this publication in new window or tab >>Ion Dynamics Across a Low Mach Number Bow Shock
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2024 (English)In: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 129, no 4, article id e2023JA032296Article in journal (Refereed) Published
Abstract [en]

A thorough understanding of collisionless shocks requires knowledge of how different ion species are accelerated across the shock. We investigate a bow shock crossing using the Magnetospheric Multiscale spacecraft after a coronal mass ejection crossed Earth, which led to solar wind consisting of protons, alpha particles, and singly charged helium ions. The three species are resolved upstream of the shock. The low Mach number of the bow shock enabled the ions to be partly distinguished downstream of the shock due to the relatively low ion heating. Some of the protons are specularly reflected and produce quasi-periodic fine structures in the velocity distribution functions downstream of the shock. Heavier ions are shown to transit the shock without reflection. However, the gyromotion of the heavier ions partially obscures the fine structure of proton distributions. Additionally, the calculated proton moments are unreliable when the different ion species are not distinguished by the particle detector. The need for high time-resolution mass-resolving ion detectors when investigating collisionless shocks is discussed. One of the ongoing challenges when investigating collisionless shocks is determining the energy partition between electromagnetic fields and different particle species. Resolving this question requires detailed observations of the electromagnetic fields and particle distributions, and is challenging when multiple ion species are present. We investigate a crossing of Earth's bow shock for unusual solar wind conditions; three ion species are observed in the solar wind and behind the bow shock, namely protons, alpha particles, and singly charged helium ions. We investigate the ion dynamics and show that a small fraction of protons are reflected by the electric field associated with the shock, which results in complex ion distributions. However, since the highest time-resolution ion detectors cannot distinguish between different ion species, the heavier ions partly obscure the fine structure of the protons. The heavier ions lead to errors when calculating the bulk properties (e.g., moments) of protons. These observations illustrate the need for high time-resolution ion detectors, which can distinguish different ion species when studying shocks. Protons, singly charged helium ions, and alpha particles are observed upstream and downstream of a bow shock crossing The alpha particles and helium ions partly obscure the fine structure of the downstream proton distributions High time-resolution mass-resolving ion detectors are needed to study the ion dynamics across collisionless shocks

Place, publisher, year, edition, pages
American Geophysical Union (AGU), 2024
Keywords
shocks, bow shock, particle acceleration
National Category
Fusion, Plasma and Space Physics
Identifiers
urn:nbn:se:uu:diva-526200 (URN)10.1029/2023JA032296 (DOI)001193298300001 ()
Funder
EU, Horizon 2020, 101004131
Available from: 2024-04-11 Created: 2024-04-11 Last updated: 2024-04-11Bibliographically approved
Trotta, D., Larosa, A., Nicolaou, G., Horbury, T. S., Matteini, L., Hietala, H., . . . Wimmer-Schweingruber, R. F. (2024). Properties of an Interplanetary Shock Observed at 0.07 and 0.7 au by Parker Solar Probe and Solar Orbiter. Astrophysical Journal, 962(2), Article ID 147.
Open this publication in new window or tab >>Properties of an Interplanetary Shock Observed at 0.07 and 0.7 au by Parker Solar Probe and Solar Orbiter
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2024 (English)In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 962, no 2, article id 147Article in journal (Refereed) Published
Abstract [en]

The Parker Solar Probe (PSP) and Solar Orbiter (SolO) missions opened a new observational window in the inner heliosphere, which is finally accessible to direct measurements. On 2022 September 5, a coronal mass ejection (CME)-driven interplanetary (IP) shock was observed as close as 0.07 au by PSP. The CME then reached SolO, which was radially well-aligned at 0.7 au, thus providing us with the opportunity to study the shock properties at different heliocentric distances. We characterize the shock, investigate its typical parameters, and compare its small-scale features at both locations. Using the PSP observations, we investigate how magnetic switchbacks and ion cyclotron waves are processed upon shock crossing. We find that switchbacks preserve their V-B correlation while compressed upon the shock passage, and that the signature of ion cyclotron waves disappears downstream of the shock. By contrast, the SolO observations reveal a very structured shock transition, with a population of shock-accelerated protons of up to about 2 MeV, showing irregularities in the shock downstream, which we correlate with solar wind structures propagating across the shock. At SolO, we also report the presence of low-energy (similar to 100 eV) electrons scattering due to upstream shocklets. This study elucidates how the local features of IP shocks and their environments can be very different as they propagate through the heliosphere.

Place, publisher, year, edition, pages
Institute of Physics (IOP), 2024
National Category
Astronomy, Astrophysics and Cosmology
Identifiers
urn:nbn:se:uu:diva-524413 (URN)10.3847/1538-4357/ad187d (DOI)001162940600001 ()
Funder
EU, Horizon 2020, 101004159EU, European Research Council, IN110921
Available from: 2024-03-06 Created: 2024-03-06 Last updated: 2024-03-06Bibliographically approved
Colomban, L., Kretzschmar, M., Krasnoselkikh, V., Agapitov, O. V., Froment, C., Maksimovic, M., . . . Bale, S. (2024). Quantifying the diffusion of suprathermal electrons by whistler waves between 0.2 and 1 AU with Solar Orbiter and Parker Solar Probe. Astronomy and Astrophysics, 684, Article ID A143.
Open this publication in new window or tab >>Quantifying the diffusion of suprathermal electrons by whistler waves between 0.2 and 1 AU with Solar Orbiter and Parker Solar Probe
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2024 (English)In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 684, article id A143Article in journal (Refereed) Published
Abstract [en]

Context. The evolution of the solar wind electron distribution function with heliocentric distance exhibits different features that are still unexplained, in particular, the fast decrease in the electron heat flux and the increase in the Strahl pitch angle width. Wave-particle interactions between electrons and whistler waves are often proposed to explain these phenomena.

Aims. We aim to quantify the effect of whistler waves on suprathermal electrons as a function of heliocentric distance.

Methods. We first performed a statistical analysis of whistler waves (occurrence and properties) observed by Solar Orbiter and Parker Solar Probe between 0.2 and 1 AU. The wave characteristics were then used to compute the diffusion coefficients for solar wind suprathermal electrons in the framework of quasi-linear theory. These coefficients were integrated to deduce the overall effect of whistler waves on electrons along their propagation.

Results. About 110 000 whistler wave packets were detected and characterized in the plasma frame, including their direction of propagation with respect to the background magnetic field and their radial direction of propagation. Most waves are aligned with the magnetic field and only ∼0.5% of them have a propagation angle greater than 45°. Beyond 0.3 AU, it is almost exclusively quasi-parallel waves propagating anti-sunward (some of them are found sunward but are within switchbacks with a change of sign of the radial component of the background magnetic) that are observed. Thus, these waves are found to be Strahl-aligned and not counter-streaming. At 0.2 AU, we find both Strahl-aligned and counter-streaming quasi-parallel whistler waves.

Conclusions. Beyond 0.3 AU, the integrated diffusion coefficients show that the observed waves are sufficient to explain the measured Strahl pitch angle evolution and effective in isotropizing the halo. Strahl diffusion is mainly attributed to whistler waves with a propagation angle of θ ∈ [15.45]°, although their origin has not yet been fully determined. Near 0.2 AU, counter-streaming whistler waves are able to diffuse the Strahl electrons more efficiently than the Strahl-aligned waves by two orders of magnitude.

Place, publisher, year, edition, pages
EDP Sciences, 2024
Keywords
diffusion, plasmas, waves, Sun: heliosphere, solar wind
National Category
Astronomy, Astrophysics and Cosmology Fusion, Plasma and Space Physics
Identifiers
urn:nbn:se:uu:diva-527987 (URN)10.1051/0004-6361/202347489 (DOI)001203444100014 ()
Available from: 2024-05-13 Created: 2024-05-13 Last updated: 2024-05-13Bibliographically approved
Richard, L., Sorriso-Valvo, L., Yordanova, E., Graham, D. B. & Khotyaintsev, Y. V. (2024). Turbulence in Magnetic Reconnection Jets from Injection to Sub-Ion Scales. Physical Review Letters, 132(10), Article ID 105201.
Open this publication in new window or tab >>Turbulence in Magnetic Reconnection Jets from Injection to Sub-Ion Scales
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2024 (English)In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 132, no 10, article id 105201Article in journal (Refereed) Published
Abstract [en]

We investigate turbulence in magnetic reconnection jets in the Earth’s magnetotail using data from the Magnetospheric Multiscale spacecraft. We show that signatures of a limited inertial range are observed in many reconnection jets. The observed turbulence develops on the timescale of a few ion gyroperiods, resulting in intermittent multifractal energy cascade from the characteristic scale of the jet down to the ion scales. We show that at sub-ion scales, the fluctuations are close to monofractal and predominantly kinetic Alfvén waves. The observed energy transfer rate across the inertial range is ∼108  J kg−1 s−1, which is the largest reported for space plasmas so far.

Place, publisher, year, edition, pages
American Physical Society, 2024
National Category
Fusion, Plasma and Space Physics
Identifiers
urn:nbn:se:uu:diva-516435 (URN)10.1103/PhysRevLett.132.105201 (DOI)001196477400008 ()38518330 (PubMedID)
Funder
Swedish National Space Board, 139/18Swedish National Space Board, 145/18Swedish Research Council, 2022-03352
Available from: 2023-11-21 Created: 2023-11-21 Last updated: 2024-04-19Bibliographically approved
Svenningsson, I., Yordanova, E., Khotyaintsev, Y. V., André, M., Cozzani, G. & Steinvall, K. (2024). Whistler Waves in the Quasi-Parallel and Quasi-Perpendicular Magnetosheath. Journal of Geophysical Research - Space Physics, 129(6), Article ID e2024JA032661.
Open this publication in new window or tab >>Whistler Waves in the Quasi-Parallel and Quasi-Perpendicular Magnetosheath
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2024 (English)In: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 129, no 6, article id e2024JA032661Article in journal (Refereed) Published
Abstract [en]

In the Earth's magnetosheath (MSH), several processes contribute to energy dissipation and plasma heating, one of which is wave-particle interactions between whistler waves and electrons. However, the overall impact of whistlers on electron dynamics in the MSH remains to be quantified. We analyze 18 hr of burst-mode measurements from the Magnetospheric Multiscale (MMS) mission, including data from the unbiased magnetosheath campaign during February-March 2023. We present a statistical study of 34,409 whistler waves found using automatic detection. We compare wave occurrence in the different MSH geometries and find three times higher occurrence in the quasi-perpendicular MSH compared to the quasi-parallel case. We also study the wave properties and find that the waves propagate quasi-parallel to the background magnetic field, have a median frequency of 0.2 times the electron cyclotron frequency, median amplitude of 0.03-0.06 nT (30-60 pT), and median duration of a few tens of wave periods. The whistler waves are preferentially observed in local magnetic dips and density peaks and are not associated with an increased temperature anisotropy. Also, almost no whistlers are observed in regions with parallel electron plasma beta lower than 0.1. Importantly, when estimating pitch-angle diffusion times we find that the whistler waves cause significant pitch-angle scattering of electrons in the MSH. Whistlers exist throughout the magnetosheath with higher occurrence in the quasi-perpendicular geometry and in local magnetic field dips Whistlers are observed in regions with electron beta above 0.1 and are not correlated with electron temperature anisotropy Whistlers cause significant pitch-angle scattering of magnetosheath electrons

Place, publisher, year, edition, pages
American Geophysical Union (AGU), 2024
Keywords
magnetosheath, whistler waves, pitch-angle diffusion, cyclotron resonance
National Category
Fusion, Plasma and Space Physics Astronomy, Astrophysics and Cosmology
Identifiers
urn:nbn:se:uu:diva-534073 (URN)10.1029/2024JA032661 (DOI)001247258800001 ()
Funder
Swedish Research CouncilSwedish National Space Board, 145/18Swedish National Space Board, 192/20
Available from: 2024-07-03 Created: 2024-07-03 Last updated: 2024-07-03Bibliographically approved
Gao, C.-H., Tang, B.-B., Guo, X.-C., Li, W. Y., Khotyaintsev, Y. V., Graham, D. B., . . . Wang, C. (2023). Agyrotropic Electron Distributions in the Terrestrial Foreshock Transients. Geophysical Research Letters, 50(4), Article ID e2022GL102235.
Open this publication in new window or tab >>Agyrotropic Electron Distributions in the Terrestrial Foreshock Transients
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2023 (English)In: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 50, no 4, article id e2022GL102235Article in journal (Refereed) Published
Abstract [en]

Agyrotropic electron distributions are frequently taken as an indicator of electron diffusion regions of magnetic reconnection. However, they have also been found at electron-scale boundaries of the non-reconnecting magnetopause and are generated by the electron finite gyroradius effect. Here, we present magnetospheric multiscale observations of agyrotropic electron distributions in the foreshock region. These distributions are generated by the electron finite gyroradius effect after magnetic curvature scattering at a thin electron-scale boundary. Meanwhile, the signatures of magnetic reconnection are absent at this boundary. The test-particle simulation is adopted to verify the generation of the agyrotropic electron distributions by assuming one-dimensional magnetic geometry. These observations suggest that agyrotropic electron distributions can be more widely formed at electron-scale boundaries in space plasma environment.

Plain Language Summary

The agyrotropic electron distributions, which could be unstable to generate high frequency electrostatic waves, reveal valuable information of electron dynamics at electron scales. However, due to electron's small mass, the related observational study becomes only possible with the high-resolution magnetospheric multiscale data. In this study, we show that the agyrotropic electron distributions can be also formed in the foreshock transients such as inside an hot flow anomaly, suggesting that agyrotropic electron distributions are ubiquitous in space plasma.

Place, publisher, year, edition, pages
American Geophysical Union (AGU), 2023
Keywords
agyrotropic electron distributions, foreshock transients
National Category
Geophysics
Identifiers
urn:nbn:se:uu:diva-500026 (URN)10.1029/2022GL102235 (DOI)000949576300001 ()
Available from: 2023-04-11 Created: 2023-04-11 Last updated: 2023-04-18Bibliographically approved
Dimmock, A. P., Gedalin, M., Lalti, A., Trotta, D., Khotyaintsev, Y. V., Graham, D. B., . . . Wimmer-Schweingruber, R. F. (2023). Backstreaming ions at a high Mach number interplanetary shock: Solar Orbiter measurements during the nominal mission phase. Astronomy and Astrophysics, 679, Article ID A106.
Open this publication in new window or tab >>Backstreaming ions at a high Mach number interplanetary shock: Solar Orbiter measurements during the nominal mission phase
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2023 (English)In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 679, article id A106Article in journal (Refereed) Published
Abstract [en]

Context: Solar Orbiter, a mission developed by the European Space Agency, explores in situ plasma across the inner heliosphere while providing remote-sensing observations of the Sun. The mission aims to study the solar wind, but also transient structures such as interplanetary coronal mass ejections and stream interaction regions. These structures often contain a leading shock wave that can differ from other plasma shock waves, such as those around planets. Importantly, the Mach number of these interplanetary shocks is typically low (1-3) compared to planetary bow shocks and most astrophysical shocks. However, our shock survey revealed that on 30 October 2021, Solar Orbiter measured a shock with an Alfven Mach number above 6, which can be considered high in this context.

Aims: Our study examines particle observations for the 30 October 2021 shock. The particles provide clear evidence of ion reflection up to several minutes upstream of the shock. Additionally, the magnetic and electric field observations contain complex electromagnetic structures near the shock, and we aim to investigate how they are connected to ion dynamics. The main goal of this study is to advance our understanding of the complex coupling between particles and the shock structure in high Mach number regimes of interplanetary shocks.

Methods: We used observations of magnetic and electric fields, probe-spacecraft potential, and thermal and energetic particles to characterize the structure of the shock front and particle dynamics. Furthermore, ion velocity distribution functions were used to study reflected ions and their coupling to the shock. To determine shock parameters and study waves, we used several methods, including cold plasma theory, singular-value decomposition, minimum variance analysis, and shock Rankine-Hugoniot relations. To support the analysis and interpretation of the experimental data, test-particle analysis, and hybrid particle in-cell simulations were used.

Results: The ion velocity distribution functions show clear evidence of particle reflection in the form of backstreaming ions several minutes upstream. The shock structure has complex features at the ramp and whistler precursors. The backstreaming ions may be modulated by the complex shock structure, and the whistler waves are likely driven by gyrating ions in the foot. Supra-thermal ions up to 20 keV were observed, but shock-accelerated particles with energies above this were not.

Place, publisher, year, edition, pages
EDP Sciences, 2023
Keywords
Sun: coronal mass ejections (CMEs), solar wind, shock waves, plasmas, waves, instabilities
National Category
Astronomy, Astrophysics and Cosmology Fusion, Plasma and Space Physics
Identifiers
urn:nbn:se:uu:diva-522677 (URN)10.1051/0004-6361/202347006 (DOI)001112445000021 ()
Funder
Swedish National Space Board, 2020-00111EU, Horizon 2020, 101004131EU, Horizon 2020, 101004159
Available from: 2024-02-08 Created: 2024-02-08 Last updated: 2024-02-08Bibliographically approved
Cozzani, G., Khotyaintsev, Y. V., Graham, D. B. & André, M. (2023). Direct Observations of Electron Firehose Fluctuations in the Magnetic Reconnection Outflow. Journal of Geophysical Research - Space Physics, 128(5), Article ID e2022JA031128.
Open this publication in new window or tab >>Direct Observations of Electron Firehose Fluctuations in the Magnetic Reconnection Outflow
2023 (English)In: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 128, no 5, article id e2022JA031128Article in journal (Refereed) Published
Abstract [en]

Electron temperature anisotropy-driven instabilities such as the electron firehose instability (EFI) are especially significant in space collisionless plasmas, where collisions are so scarce that wave-particle interactions are the leading mechanisms in the isotropization of the distribution function and energy transfer. Observational statistical studies provided convincing evidence in favor of the EFI constraining the electron distribution function and limiting the electron temperature anisotropy. Magnetic reconnection is characterized by regions of enhanced temperature anisotropy that could drive instabilities-including the electron firehose instability-affecting the particle dynamics and the energy conversion. However, in situ observations of the fluctuations generated by the EFI are still lacking and the interplay between magnetic reconnection and EFI is still largely unknown. In this study, we use high-resolution in situ measurements by the Magnetospheric Multiscale spacecraft to identify and investigate EFI fluctuations in the magnetic reconnection exhaust in the Earth's magnetotail. We find that the wave properties of the observed fluctuations largely agree with theoretical predictions of the non-propagating EF mode. These findings are further supported by comparison with the linear kinetic dispersion relation. Our results demonstrate that the magnetic reconnection outflow can be the seedbed of EFI and provide the first direct in situ observations of EFI-generated fluctuations.

Place, publisher, year, edition, pages
American Geophysical Union (AGU), 2023
Keywords
plasma instabilities, electron firehose instability, magnetic reconnection, collisionless plasmas, spacecraft observations
National Category
Astronomy, Astrophysics and Cosmology Fusion, Plasma and Space Physics
Identifiers
urn:nbn:se:uu:diva-505236 (URN)10.1029/2022JA031128 (DOI)001000427100001 ()
Funder
Swedish National Space Board, 128/17
Available from: 2023-06-26 Created: 2023-06-26 Last updated: 2023-06-26Bibliographically approved
Wang, H.-W. -., Tang, B.-B. -., Li, W. Y., Zhang, Y.-C. -., Graham, D. B., Khotyaintsev, Y. V., . . . Wang, C. (2023). Electron Dynamics in the Electron Current Sheet During Strong Guide-Field Reconnection. Geophysical Research Letters, 50(10), Article ID e2023GL103046.
Open this publication in new window or tab >>Electron Dynamics in the Electron Current Sheet During Strong Guide-Field Reconnection
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2023 (English)In: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 50, no 10, article id e2023GL103046Article in journal (Refereed) Published
Abstract [en]

In this study, we investigate detailed electron dynamics in strong guide-field reconnection (the normalized guide field is similar to 1.5). This reconnection event is observed by the Magnetospheric Multiscale (MMS) spacecraft at the center of a flux rope in the magnetotail. With the presence of a large parallel electric field (E-||) in the electron current sheet, electrons are accelerated when streaming into this E-|| region from one direction, and decelerated from the other direction. Some decelerated electrons can reduce the parallel speed to similar to 0 to form relatively isotropic electron distributions at one side of the electron current sheet, as the estimated acceleration potential satisfies the relation e Phi(||) >= kT(e,||), where T-e,T-|| is the electron temperature parallel to the magnetic field. Therefore, a large E-|| is generated to balance the parallel electron pressure gradient across the electron current sheet, since electrons at the other side of the current sheet are still anisotropic. Based on these observations, we further show that the electron beta is an important parameter in guide-field reconnection, providing a new perspective to solve the large parallel electric field puzzle in guide-field reconnection. Plain Language Summary Magnetic reconnection is a universal process that rapidly converts energy from the magnetic field to plasma. The energy conversion at kinetic scales is of particular interest to researchers, as it is directly related to reconnection process in the central diffusion region. In general, the reconnecting magnetic fields do not have to be antiparallel, and an additional magnetic component known as the guide field (B-g) can appear in the direction perpendicular to the reconnecting plane. Recently, observations from Magnetospheric Multiscale (MMS) mission show a large electric field parallel to the local magnetic field, which is several times larger than the reconnection electric field, can appear in guide-field reconnection, and impact electrons significantly. However, the generation of this large parallel electric field in strong guide-field reconnection is still not fully understood. In this study, we suggest that the electron beta (ratio of the electron thermal pressure to the magnetic pressure) is an important parameter in guide-field reconnection. Only within some proper electron beta range, a parallel pressure gradient across the electron current sheet can form to balance the large parallel electric field.

Place, publisher, year, edition, pages
American Geophysical Union (AGU), 2023
National Category
Fusion, Plasma and Space Physics
Identifiers
urn:nbn:se:uu:diva-505286 (URN)10.1029/2023GL103046 (DOI)000999864200001 ()
Available from: 2023-06-29 Created: 2023-06-29 Last updated: 2023-06-30Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0001-5550-3113

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