Articles | Volume 37, issue 2
https://doi.org/10.5194/angeo-37-243-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/angeo-37-243-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
17 Apr 2019
Regular paper |
| 17 Apr 2019
| 17 Apr 2019
Reflection of the strahl within the foot of the Earth's bow shock
Christopher A. Gurgiolo
Bitterroot Basic Research, Hamilton, MT 59840, USA
deceased
Melvyn L. Goldstein
CORRESPONDING AUTHOR
Space Science Institute, Boulder, CO 80301, USA
Adolfo Viñas
Department of Physics, American University, Washington, DC 20016,
USA, and Geospace Physics Laboratory, NASA Goddard Space Flight Center,
Greenbelt, MD 20771, USA
Related authors
Chris Gurgiolo and Melvyn L. Goldstein
Ann. Geophys., 35, 71–85, https://doi.org/10.5194/angeo-35-71-2017, https://doi.org/10.5194/angeo-35-71-2017, 2017
Short summary
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Observations during periods when the solar wind has a speed < 425 km s−1 show that it is not uncommon to find no strahl present in the data. The research was done in response to observations and was performed through a detailed study of the electron velocity distribution functions. The conclusion arrived at is that the absence of the strahl appears to occur within individual flux tubes, which may indicate that the source lies in the solar corona where the strahl is formed.
Chris Gurgiolo and Melvyn L. Goldstein
Ann. Geophys., 34, 1175–1189, https://doi.org/10.5194/angeo-34-1175-2016, https://doi.org/10.5194/angeo-34-1175-2016, 2016
Short summary
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Using Cluster data we have noted observations of diffusion-like signatures in the energy range where the the solar wind halo and strahl populations overlap. This includes the development of a proto-halo. At present the source of this diffusion is not known or understood. The prime analysis was carried out through the use of phi–theta plots at individual energy steps. The motivation was to understand if repartitioning in energy was occurring at these locations.
Chris Gurgiolo and Melvyn L. Goldstein
Ann. Geophys., 35, 71–85, https://doi.org/10.5194/angeo-35-71-2017, https://doi.org/10.5194/angeo-35-71-2017, 2017
Short summary
Short summary
Observations during periods when the solar wind has a speed < 425 km s−1 show that it is not uncommon to find no strahl present in the data. The research was done in response to observations and was performed through a detailed study of the electron velocity distribution functions. The conclusion arrived at is that the absence of the strahl appears to occur within individual flux tubes, which may indicate that the source lies in the solar corona where the strahl is formed.
Chris Gurgiolo and Melvyn L. Goldstein
Ann. Geophys., 34, 1175–1189, https://doi.org/10.5194/angeo-34-1175-2016, https://doi.org/10.5194/angeo-34-1175-2016, 2016
Short summary
Short summary
Using Cluster data we have noted observations of diffusion-like signatures in the energy range where the the solar wind halo and strahl populations overlap. This includes the development of a proto-halo. At present the source of this diffusion is not known or understood. The prime analysis was carried out through the use of phi–theta plots at individual energy steps. The motivation was to understand if repartitioning in energy was occurring at these locations.
C. P. Escoubet, A. Masson, H. Laakso, and M. L. Goldstein
Ann. Geophys., 33, 1221–1235, https://doi.org/10.5194/angeo-33-1221-2015, https://doi.org/10.5194/angeo-33-1221-2015, 2015
Short summary
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This paper presents recent highlights from the Cluster mission on solar wind turbulence, magnetopause asymmetries and magnetosheath density enhancements, dipolarisation currents, reconnection variability, FTE in greatest detail, plasmaspheric wind and re-filling of the plasmasphere, radiation belts, updates of magnetospheric electric and magnetic field models, and magnetosheath and magnetopause properties under low Mach number. Public access to all high-resolution data (CSA) is also presented.
C. Gurgiolo, M. L. Goldstein, W. H. Matthaeus, A. Viñas, and A. N. Fazakerley
Ann. Geophys., 31, 2063–2075, https://doi.org/10.5194/angeo-31-2063-2013, https://doi.org/10.5194/angeo-31-2063-2013, 2013
C. P. Escoubet, M. G. G. T. Taylor, A. Masson, H. Laakso, J. Volpp, M. Hapgood, and M. L. Goldstein
Ann. Geophys., 31, 1045–1059, https://doi.org/10.5194/angeo-31-1045-2013, https://doi.org/10.5194/angeo-31-1045-2013, 2013
Related subject area
Subject: Magnetosphere & space plasma physics | Keywords: Bow shock and foreshock
Short large-amplitude magnetic structures (SLAMS) at Mercury observed by MESSENGER
Fine structure and motion of the bow shock and particle energisation mechanisms inferred from Magnetospheric Multiscale (MMS) observations
Foreshock cavitons and spontaneous hot flow anomalies: a statistical study with a global hybrid-Vlasov simulation
Evidence of the nonstationarity of the terrestrial bow shock from multi-spacecraft observations: methodology, results, and quantitative comparison with particle-in-cell (PIC) simulations
A deep insight into the ion foreshock with the help of test particle two-dimensional simulations
Helium in the Earth's foreshock: a global Vlasiator survey
Non-locality of Earth's quasi-parallel bow shock: injection of thermal protons in a hybrid-Vlasov simulation
Low-frequency magnetic variations at the high-β Earth bow shock
Comment on “Cavitons and spontaneous hot flow anomalies in a hybrid-Vlasov global magnetospheric simulation” by Blanco-Cano et al. (2018)
Cavitons and spontaneous hot flow anomalies in a hybrid-Vlasov global magnetospheric simulation
Tomas Karlsson, Ferdinand Plaschke, Austin N. Glass, and Jim M. Raines
Ann. Geophys., 42, 117–130, https://doi.org/10.5194/angeo-42-117-2024, https://doi.org/10.5194/angeo-42-117-2024, 2024
Short summary
Short summary
The solar wind interacts with the planets in the solar system and creates a supersonic shock in front of them. The upstream region of this shock contains many complicated phenomena. One such phenomenon is small-scale structures of strong magnetic fields (SLAMS). These SLAMS have been observed at Earth and are important in determining the properties of space around the planet. Until now, SLAMS have not been observed at Mercury, but we show for the first time that SLAMS also exist there.
Krzysztof Stasiewicz and Zbigniew Kłos
Ann. Geophys., 40, 315–325, https://doi.org/10.5194/angeo-40-315-2022, https://doi.org/10.5194/angeo-40-315-2022, 2022
Short summary
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The acceleration, or energisation, of particles is a common and fundamental process throughout the universe. This study presents new observations of the acceleration of protons by waves at the bow shock upstream of the Earth, where the solar wind first encounters Earth’s magnetic field. The results are important, because they provide insight into acceleration processes that can create high-energy particles both near the Earth and at other astrophysical systems.
Vertti Tarvus, Lucile Turc, Markus Battarbee, Jonas Suni, Xóchitl Blanco-Cano, Urs Ganse, Yann Pfau-Kempf, Markku Alho, Maxime Dubart, Maxime Grandin, Andreas Johlander, Konstantinos Papadakis, and Minna Palmroth
Ann. Geophys., 39, 911–928, https://doi.org/10.5194/angeo-39-911-2021, https://doi.org/10.5194/angeo-39-911-2021, 2021
Short summary
Short summary
We use simulations of Earth's magnetosphere and study the formation of transient wave structures in the region where the solar wind first interacts with the magnetosphere. These transients move earthward and play a part in the solar wind–magnetosphere interaction. We show that the transients are a common feature and their properties are altered as they move earthward, including an increase in temperature, decrease in solar wind speed and an alteration in their propagation properties.
Christian Mazelle and Bertrand Lembège
Ann. Geophys., 39, 571–598, https://doi.org/10.5194/angeo-39-571-2021, https://doi.org/10.5194/angeo-39-571-2021, 2021
Short summary
Short summary
Nonstationarity of the quasi-perpendicular terrestrial bow shock is analyzed from magnetic field measurements, comparison with 2D particle-in-cell (PIC) simulations, and a careful and accurate methodology in the data processing. The results show evidence of a strong variability of the microstructures of the shock front (foot and ramp), confirming the importance of dissipative effects. These results indicate that these features can be signatures of the shock front self-reformation.
Philippe Savoini and Bertrand Lembège
Ann. Geophys., 38, 1217–1235, https://doi.org/10.5194/angeo-38-1217-2020, https://doi.org/10.5194/angeo-38-1217-2020, 2020
Short summary
Short summary
Numerical simulations have been used to investigate some acceleration mechanisms in order to explain the origin of the energized back-streaming ions observed at the Earth's bow shock. This paper used test particles in two different configurations with self-consistent and fixed shock front profiles. The comparison of these two configurations allows us to analyze, in detail, the impact of the shock front nonstationarity and the role of the built-up electric field in the acceleration process.
Markus Battarbee, Xóchitl Blanco-Cano, Lucile Turc, Primož Kajdič, Andreas Johlander, Vertti Tarvus, Stephen Fuselier, Karlheinz Trattner, Markku Alho, Thiago Brito, Urs Ganse, Yann Pfau-Kempf, Mojtaba Akhavan-Tafti, Tomas Karlsson, Savvas Raptis, Maxime Dubart, Maxime Grandin, Jonas Suni, and Minna Palmroth
Ann. Geophys., 38, 1081–1099, https://doi.org/10.5194/angeo-38-1081-2020, https://doi.org/10.5194/angeo-38-1081-2020, 2020
Short summary
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We investigate the dynamics of helium in the foreshock, a part of near-Earth space found upstream of the Earth's bow shock. We show how the second most common ion in interplanetary space reacts strongly to plasma waves found in the foreshock. Spacecraft observations and supercomputer simulations both give us a new understanding of the foreshock edge and how to interpret future observations.
Markus Battarbee, Urs Ganse, Yann Pfau-Kempf, Lucile Turc, Thiago Brito, Maxime Grandin, Tuomas Koskela, and Minna Palmroth
Ann. Geophys., 38, 625–643, https://doi.org/10.5194/angeo-38-625-2020, https://doi.org/10.5194/angeo-38-625-2020, 2020
Short summary
Short summary
The structure and medium-scale dynamics of Earth's bow shock and how charged solar wind particles are reflected by it are studied in order to better understand space weather effects. We use advanced supercomputer simulations to model the shock and reflected ions. We find that the thickness of the shock depends on solar wind conditions but also has small-scale variations. Charged particle reflection is shown to be non-localized. Magnetic fields are important for ion reflection.
Anatoli A. Petrukovich, Olga M. Chugunova, and Pavel I. Shustov
Ann. Geophys., 37, 877–889, https://doi.org/10.5194/angeo-37-877-2019, https://doi.org/10.5194/angeo-37-877-2019, 2019
Short summary
Short summary
Earth's bow shock in solar wind with high thermal and low magnetic pressure is a rare phenomenon. However, such an object is ubiquitous in astrophysical plasmas.
We surveyed statistics of such shock observations since 1995. About 100 crossings were initially identified. In this report 22 crossings from the Cluster project were studied using multipoint analysis, which allowed for the determination of the spatial scales of the shock transition and of the dominant magnetic variations
Gábor Facskó
Ann. Geophys., 37, 763–764, https://doi.org/10.5194/angeo-37-763-2019, https://doi.org/10.5194/angeo-37-763-2019, 2019
Short summary
Short summary
Blanco-Cano et al. (2018) intended to find a type of transient event in the solar wind before the terrestrial bow shock using a special type of simulation. However, the simulation results cannot reproduce the main features of the event. Based on the remarks described below, I am sure that the features in the simulations are not those types of events. The Vlasiator code simulated proto-SHFAs.
Xochitl Blanco-Cano, Markus Battarbee, Lucile Turc, Andrew P. Dimmock, Emilia K. J. Kilpua, Sanni Hoilijoki, Urs Ganse, David G. Sibeck, Paul A. Cassak, Robert C. Fear, Riku Jarvinen, Liisa Juusola, Yann Pfau-Kempf, Rami Vainio, and Minna Palmroth
Ann. Geophys., 36, 1081–1097, https://doi.org/10.5194/angeo-36-1081-2018, https://doi.org/10.5194/angeo-36-1081-2018, 2018
Short summary
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We use the Vlasiator code to study the characteristics of transient structures that exist in the Earth's foreshock, i.e. upstream of the bow shock. The structures are cavitons and spontaneous hot flow anomalies (SHFAs). These transients can interact with the bow shock. We study the changes the shock suffers via this interaction. We also investigate ion distributions associated with the cavitons and SHFAs. A very important result is that the arrival of multiple SHFAs results in shock erosion.
Cited articles
Anderson, K. A., Lin, R. P., Gurgiolo, C., Parks, G. K., Potter, D. W., Werden,
S., and Rème, H.: A component of nongyrotropic (phase bunched)
electrons upstream from the Earth's bow shock, J. Geophys. Res.-Atmos., 90, 10809, https://doi.org/10.1029/JA090iA11p10809, 1985. a
Bale, S. D., Burgess, D., Kellogg, P. J., Goetz, K., and Monson, S. J.: On the
amplitude of intense Langmuir waves in the terrestrial electron foreshock,
J. Geophys. Res.-Atmos., 102, 11281–11286, https://doi.org/10.1029/97JA00938, 1997. a
Balogh, A., Dunlop, M. W., Cowley, S. W. H., Southwood, D. J., Thomlinson,
J. G., Glassmeier, K. H., Musmann, G., Luhr, H., Buchert, S., Acuna, M. H.,
Fairfield, D. H., Slavin, J. A., Riedler, W., Schwingenschuh, K., and
Kivelson, M. G.: The Cluster Magnetic Field Investigation, Space Sci.
Rev., 79, 65–91, https://doi.org/10.1023/A:1004970907748, 1997. a
Bonifazi, C. and Moreno, G.: Reflected and diffuse ions backstreaming from the
earth's bow shock, 1, Basic Properties, J. Geophys. Res.-Atmos., 86, 4397–4413, 1981a. a
Bonifazi, C. and Moreno, G.: Reflected and diffuse ions backstreaming from the
earth's bow shock, 2, Origin, J. Geophys. Res.–Atmos., 86, 4405–4414, https://doi.org/10.1029/JA086iA06p04405, 1981b. a
Burgess, D. and Schwartz, S. J.: The dynamics and upstream distributions of
ions reflected at the Earth's bow shock, J. Geophys. Res.-Atmos., 89, 7407–7422, 1984. a
Décréau, P. M. E., Fergeau, P., Krannosels'kikh, V., Leveque, M.,
Martin, P., Randriamboarison, O., Sene, F. X., Trotignon, J. G., Canu, P.,
and Mogensen, P. B.: Whisper, a Resonance Sounder and Wave Analyser:
Performances and Perspectives for the Cluster Mission, Space Sci. Rev.,
79, 157–193, https://doi.org/10.1023/A:1004931326404, 1997. a
Fazakerley, A. N., Lahiff, A. D., Wilson, R. J., Rozum, I., Anekallu, C., West,
M., and Bacai, H.: PEACE Data in the Cluster Active Archive, The Cluster
Active Archive, Studying the Earth's Space Plasma Environment, edited by:
Laakso, H., Taylor, M. G. T. T., and Escoubet, C. P., Astrophysics Space, 11, 129–144,
https://doi.org/10.1007/978-90-481-3499-1_8, 2010. a
Fitzenreiter, R. J., Viňas, A. F., Klimas, A. J., Lepping, R. P., Kaiser,
M. L., and Onsager, T. G.: Wind observations of the electron foreshock,
Geophys. Res. Lett., 23, 1235–1238, https://doi.org/10.1029/96GL00826, 1996. a
Fuselier, S. A. and Schmidt, W. K. H.: H+ and He2+ heating at the Earth's bow
shock, J. Geophys. Res.-Atmos., 99, 11539–11546, https://doi.org/10.1029/94JA00350, 1994. a
Gedalin, M.: Transmitted, reflected, quasi-reflected, and multiply reflected
ions in low-Mach number shocks, J. Geophys. Res.-Space, 121, 10754–10767, https://doi.org/10.1002/2016JA023395, 2016. a
Gloag, J. M., Lucek, E. A., Alconcel, L.-N., Balogh, A., Brown, P., Carr,
C. M., Dunford, C. N., Oddy, T., and Soucek, J.: FGM Data Products in the
CAA, The Cluster Active Archive, Studying the Earth's Space Plasma
Environment, edited by: Laakso, H., Taylor, M. G. T. T., and Escoubet, C. P.,
Astrophysics Space, 11, 109–128, https://doi.org/10.1007/978-90-481-3499-1_7, 2010. a
Gosling, J. T., Asbridge, J. R., Bame, S. J., Paschmann, G., and Sckopke, N.:
Observations of two distinct populations of bow shock ions in the upstream
solar wind, Geophys. Res. Lett., 5, 957–960, https://doi.org/10.1029/GL005i011p00957, 1978. a
Gosling, J. T., Thomsen, M. F., Bame, S. J., Feldman, W. C., Paschmann, G., and
Sckopke, N.: Evidence for specularly reflected ions upstream from the
quasi-parallel bow shock, Geophys. Res. Lett., 9, 1333–1336,
https://doi.org/10.1029/GL009i012p01333, 1982. a
Greenstadt, E. W., Le, G., and Strangeway, R. J.: ULF waves in the foreshock,
Adv. Space Res., 15, 71–84, 1995. a
Gurgiolo, C. and Goldstein, M. L.: Observations of diffusion in the electron
halo and strahl, Ann. Geophys., 34, 1175–1189,
https://doi.org/10.5194/angeo-34-1175-2016, 2016. a
Gurgiolo, C., Parks, G. K., and Mauk, B. H.: Upstream gyrophase bunched ions: A
mechanism for creation at the bow shock and the growth of velocity space
structure through gyrophase mixing, J. Geophys. Res., 88, 9093–9100, https://doi.org/10.1029/JA088iA11p09093, 1983. a
Gurgiolo, C., Wong, H. K., and Winske, D.: Low and high frequency waves
generated by gyrophase bunched ions at oblique shocks, Geophys. Res.
Lett., 20, 783–786, https://doi.org/10.1029/93GL00854, 1993. a, b
Gurgiolo, C., Larson, D., Lin, R. P., and Wong, H. K.: A gyrophase-bunched
electron signature upstream of the Earth's bow shock, Geophys. Res. Lett., 27, 3153–3156, https://doi.org/10.1029/2000GL000065, 2000. a
Gurgiolo, C., Goldstein, M. L., Narita, Y., Glassmeier, K. H., and Fazakerley,
A. N.: A phase locking mechansim for non-gyrotropic electron distributions
upstream of the Earth's bow shock, J. Geophys. Res.-Atmos., 110, A06206,
https://doi.org/10.1029/2005JA011010, 2005. a, b, c
Gurgiolo, C., Goldstein, M. L., Viñas, A. F., and Fazakerley, A. N.: First
measurements of electron vorticity in the foreshock and solar wind, Ann.
Geophys., 28, 2187–2200, https://doi.org/10.5194/angeo-28-2187-2010, 2010. a
Gurnett, D. A. and Frank, L. A.: Ion acoustic waves in the solar wind, J.
Geophys. Res., 83, 58–74, https://doi.org/10.1029/JA083iA01p00058, 1978. a
Gustafsson, G., Bostrom, R., Holback, B., Holmgren, G., Lundgren, A.,
Stasiewicz, K., Ahlen, L., Mozer, F. S., Pankow, D., Harvey, P., Berg, P.,
Ulrich, R., Pedersen, A., Schmidt, R., Butler, A., Fransen, A. W. C., Klinge,
D., Thomsen, M., Falthammar, C.-G., Lindqvist, P.-A., Christenson, S.,
Holtet, J., Lybekk, B., Sten, T. A., Tanskanen, P., Lappalainen, K., and
Wygant, J.: The Electric Field and Wave Experiment for the Cluster Mission,
Space Sci. Rev., 79, 137–156, https://doi.org/10.1023/A:1004975108657, 1997. a
Hoppe, M. and Russell, C. T.: Whistler mode wave packets in the earth's
foreshock region, Nature, 287, 417–420,
https://doi.org/10.1038/287417a0, 1980. a
Hoppe, M. M., Russell, C. T., Frank, L. A., Eastman, T. E., and Greenstadt,
E. W.: Upstream hydromagnetic waves and their association with backstreaming
ion populations: ISEE 1 and 2 observations, J. Geophys. Res., 86, 4471–4492, 1981. a
Johnstone, A. D., Alsop, C., Burge, S., Carter, P. J., Coates, A. J., Coker,
A. J., Fazakerley, A. N., Grande, M., Gowen, R. A., Gurgiolo, C., Hancock,
B. K., Narheim, B., Preece, A., Sheather, P. H., Winningham, J. D., and
Woodliffe, R. D.: Peace: a Plasma Electron and Current Experiment, Space
Sci. Rev., 79, 351–398, https://doi.org/10.1023/A:1004938001388, 1997. a
Khotyaintsev, Y., Lindqvist, P.-A., Eriksson, A., and André, M.: The EFW
Data in the CAA, The Cluster Active Archive, Studying the Earth's Space
Plasma Environment, edited by: Laakso, H., Taylor, M. G. T. T., and Escoubet, C.
P., Astrophysics Space, 11, 97–108,
https://doi.org/10.1007/978-90-481-3499-1_6, 2010. a
Kis, A., Scholer, M., Klecker, B., Kucharek, H., Lucek, E. A., and Réme, H.:
Scattering of field-aligned beam ions upstream of Earth's bow shock, Ann.
Geophys., 25, 785–799, https://doi.org/10.5194/angeo-25-785-2007, 2007. a
Krauss-Varban, D. and Wu, C. S.: Fast Fermi and gradient drift acceleration of
electrons at nearly perpendicular collisionless shocks, J.
Geophys. Res., 94, 15367–15372, https://doi.org/10.1029/JA094iA11p15367, 1989. a
Kucharek, H., Möbius, E., Scholer, M., Mouikis, C., Kistler, L. M., Horbury,
T., Balogh, A., Réme, H., and Bosqued, J. M.: On the origin of field-aligned
beams at the quasi-perpendicular bow shock: multi-spacecraft observations by
Cluster, Ann. Geophys., 22, 2301–2308,
https://doi.org/10.5194/angeo-22-2301-2004, 2004. a
Larson, D. E., Lin, R. P., McFadden, J. P., Ergun, R. E., Carlson, C. W.,
Anderson, K. A., Phan, T. D., McCarthy, M. P., Parks, G. K., Rème, H.,
Bosqued, J. M., d'Uston, C., Sanderson, T. R., Wenzel, K. P., and Lepping,
R. P.: Probing the Earth's bow shock with upstream electrons, Geophys.
Res. Lett., 23, 2203–2206, https://doi.org/10.1029/96GL02382, 1996. a
Leroy, M. M. and Mangeney, A.: A theory of energization of solar wind electrons
by the earth's bow shock, Ann. Geophys., 2, 449–456, 1984. a
Leroy, M. M., Goodrich, C. C., Winske, D., Wu, C. S., and Papadopoulos, K.:
Simulation of a perpendicular bow shock, Geophys. Res. Lett., 8,
1269–1272, https://doi.org/10.1029/GL008i012p01269, 1981. a
Leroy, M. M., Winske, D., Goodrich, C. C., Wu, C. S., and Papadopoulos, K.: The
structure of perpendicular bow shocks, J. Geophys. Res., 87, 5081–5094,
https://doi.org/10.1029/JA087iA07p05081, 1982. a
Mesiane, K., Mazelle, C., Lin, R. P., LeQuéau, D., Larson, D. E., Parks,
G. K., and Lepping, R. P.: Three-dimensional observations of gyrating ion
distributions far upstream of the Earth's bow shock and their association
with low-frequency waves, J. Geophys. Res.-Atmos., 106, 5731–5742, 2001. a
Meziane, K., Mazelle, C., Wilber, M., LeQuéau, D., Eastwood, J. P., Rème, H.,
Dandouras, I., Sauvaud, J. A., Bosqued, J. M., Parks, G. K., Kistler, L. M.,
McCarthy, M., Klecker, B., Korth, A., Bavassano-Cattaneo, M.-B., Lundin, R.,
and Balogh, A.: Bow shock specularly reflected ions in the presence of
low-frequency electromagnetic waves: a case study, Ann. Geophys., 22,
2325–2335, https://doi.org/10.5194/angeo-22-2325-2004, 2004. a
Paschmann, G. and Sckopke, N.: Ion reflection and heating at the Earth's bow
shock, in: Topics in plasma-astro-, and space physics, edited by: Haerendel,
G. and Battrick, B., Max-Plank-Institute fur Physick and Astrophysik,
Garching, Germany, 139–146, 1983. a
Paschmann, G., Sckopke, N., Asbridge, J. R., Bame, S. J., and Gosling, J. T.:
Energization of solar wind ions by reflection from the earth's bow shock,
J. Geophys. Res., 85, 4689–4693, https://doi.org/10.1029/JA085iA09p04689, 1980. a, b, c
Paschmann, G., Sckopke, N., Papamastorakis, I., Asbridge, J. R., Bame, S. J.,
and Gosling, J. T.: Characteristics of reflected and diffuse ions upstream
from the earth's bow shock, Upstream Wave and Particle Workshop, California
Institute of Technology, Jet Propulsion Laboratory, Pasadena, CA, Apr. 15,
16, 1980, J. Geophys. Res., 86, 4355–4364,
https://doi.org/10.1029/JA086iA06p04355, 1981. a, b
Robert, P., Roux, A., Harvey, C. C., Dunlop, M. W., Daly, P. W., and
Glassmeier, K. H.: Tetrahedron Geometry Factors, in: Analysis methods for
multi-spacecraft data, edited by: Paschmann, G. and Daly, P. W.,
ESA Publications Division, Keplerlaan 1, 2200 AG Noordwijk, the Netherlands, 323–348,
1998. a
Russell, C. T., Childers, D. D., and Coleman, P. J., J.: Ogo 5 observations of
upstream waves in the interplanetary medium: Discrete wave packets, J.
Geophys. Res., 76, 845, https://doi.org/10.1029/JA076i004p00845, 1971.
a
Savoini, P., Lembége, B., and Stienlet, J.: Origin of backstreaming
electrons within the quasi-perpendicular foreshock region: Two-dimensional
self-consistent PIC simulation, J. Geophys. Res., 115, A09104, https://doi.org/10.1029/2010JA015263, 2010. a
Scholer, M. and Terasawa, T.: Ion reflection and dissipation at
quasi-parallel collisionless shocks, Geophys. Res. Lett., 17, 119–122,
https://doi.org/10.1029/GL017i002p00119, 1990. a
Schwartz, S. J. and Marsch, E.: The radial evolution of a single solar wind
plasma parcel, J. Geophys. Res., 88, 9919–9932, https://doi.org/10.1029/JA088iA12p09919, 1983. a
Shen, C., Dunlop, M., Li, X., Liu, Z. X., Balogh, A., Zhang, T. L., Carr,
C. M., Shi, Q. Q., and Chen, Z. Q.: New approach for determining the normal
of the bow shock based on Cluster four-point magnetic field measurements,
J. Geophys. Res.-Space, 112, A03201, https://doi.org/10.1029/2006JA011699, 2007. a, b
Smith, C. W., Goldstein, M. L., Gary, S. P., and Russell, C. T.: Beam-driven
ion cyclotron harmonic resonances in the terrestrial foreshock, J.
Geophys. Res., 90, 1429–1434, https://doi.org/10.1029/JA090iA02p01429,
1985. a
Sonnerup, B.: Acceleration of particles reflected at a shock front, J.
Geophys. Res.-Space, 74, 1301–1304, https://doi.org/10.1029/JA074i005p01301, 1969. a, b
Thomsen, M. F.: Upstream suprathermal ions, in: Collision Shocks in the
Heliosphere: Reviews of Current Research, Geophys. Monograph 35, American Geophysical Union, Washington DC, USA, 253–270, https://doi.org/10.1029/GM035p0253, 1985. a
Thomsen, M. F., Schwartz, S. J., and Gosling, J. T.: Observational evidence on
the origin of ions upstream of the earth's bow shock, J. Geophys. Res., 88, 7843–7852,
https://doi.org/10.1029/JA088iA10p07843, 1983. a
Trotignon, J. G., Décréau, P. M. E., Rauch, J. L., Vallières,
X., Rochel, A., Kougblénou, S., Lointier, G., Facskó, G., Canu,
P., Darrouzet, F., and Masson, A.: The WHISPER Relaxation Sounder and the
CLUSTER Active Archive, The Cluster Active Archive, Studying the Earth's
Space Plasma Environment, edited by: Laakso, H., Taylor, M. G. T. T., and
Escoubet, C. P., Astrophysics Space, 11,
185–208, https://doi.org/10.1007/978-90-481-3499-1_12, 2010. a
Yuan, X., Cairns, I. H., Robinson, P. A., and Kuncic, Z.: Effects of overshoots
on electron distributions upstream and downstream of quasi-perpendicular
collisionless shocks, J. Geophys. Res.-Space, 112, A05108, https://doi.org/10.1029/2006JA011684,
2007. a, b
Zhang, Y., Matsumoto, H., and Kojima, H.: Bursts of whistler mode waves in the
upstream of the bow shock: Geotail observations, J. Geophys.
Res., 103, 20529–20540, https://doi.org/10.1029/98JA01371, 1998. a
Short summary
The reflection of solar wind electrons at the bow shock helps define the physical properties of the foreshock, the region where the interplanetary magnetic field directly connects to the bow shock. We report that the strahl, the field-aligned component of the electron solar wind distribution, appears to be nearly fully reflected at the bow shock and that the reflection occurs in the foot of the shock, implying that mirroring is not the primary cause of the electron reflection.
The reflection of solar wind electrons at the bow shock helps define the physical properties of...
