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Artykuły w czasopismach na temat „Ion cyclotron waves”

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Data publikacji: 6 września 2023

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1

Haridas, Annex Edappattu, i Rama Shankar Pandey. "Study of Low-Frequency Electromagnetic Ion-Cyclotron Wave for Ring Distribution in Magnetosphere of Saturn". Trends in Sciences 19, nr 22 (5.11.2022): 1329. http://dx.doi.org/10.48048/tis.2022.1329.

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Magnetic cyclotron waves were discovered by the Cassini-Huygens spacecraft in Saturn's atmospheric torus’ magnetic layer. They are left-handed and propagate at a minor angle to the ambient magnetic field in most areas because their frequency is close to the frequency of the aqua ions. The ion cyclotron instability caused by Saturn's neutral cloud ions helps explain their formation. They can be classified as n = 2 mode fluctuations because of the ion-ring distribution. We planned the characteristics of these waves in advance of starting this project. Our dispersion growth rates are evaluated using kinetic method analysis as well. The results were calculated and explained for the exemplary values of the magnetosphere parameters suitable for Saturn. Another potential free energy source for ion cyclotrons is temperature anisotropy. Instead of the standard Maxwell distribution, a ring distribution is employed in this study. The focus of this research is EMIC waves’ oblique propagation in the magnetic field, which changes their temperature anisotropy, ion energy density, and propagation angle. The interaction of relativistic particles with ion cyclotron waves is also included in this extension. EMIC wave size decreases with the increasing density of particles, as shown by a numerical study. A comparison of planetary studies based on data from space plasma environments and magnetospheric systems produced these results. HIGHLIGHTS Temperature anisotropy - free energy source for Ion Cyclotron waves EMIC wave size decreases with the increasing density of particles Saturn's neutral cloud ions helps the formation of ion cyclotron instability GRAPHICAL ABSTRACT

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2

Pokhotelov, O. A., L. Stenflo i P. K. Shukla. "Nonlinear interaction of electrostatic ion-cyclotron and drift waves in plasmas". Journal of Plasma Physics 56, nr 1 (sierpień 1996): 187–91. http://dx.doi.org/10.1017/s0022377800019176.

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Model equations describing the nonlinear coupling between electrostatic ion-cyclotron and drift waves are derived, taking into account the action of the low-frequency ponderomotive force associated with the ion-cyclotron waves. It is found that this interaction is governed by a pair of equations, which can be used for studying the modulational instability of a constant amplitude ion-cyclotron wave as well as the dynamics of nonlinearly coupled ion-cyclotron and drift waves.

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3

Bharuthram, R., S. V. Singh, S. K. Maharaj, S. Moolla, I. J. Lazarus, R. V. Reddy i G. S. Lakhina. "Do nonlinear waves evolve in a universal manner in dusty and other plasma environments?" Journal of Plasma Physics 80, nr 6 (14.07.2014): 825–32. http://dx.doi.org/10.1017/s0022377814000427.

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Using a fluid theory approach, this article provides a comparative study on the evolution of nonlinear waves in dusty plasmas, as well as other plasma environments, viz electron-ion, and electron-positron plasmas. Where applicable, relevance to satellite measurements is pointed out. A range of nonlinear waves from low frequency (ion acoustic and ion cyclotron waves), high frequency (electron acoustic and electron cyclotron waves) in electron-ion plasmas, ultra-low frequency (dust acoustic and dust cyclotron waves) in dusty plasmas and in electron-positron plasmas are discussed. Depending upon the plasma parameters, saw-tooth and bipolar structures are shown to evolve.

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4

Blanco-Cano, X., C. T. Russell, D. E. Huddleston i R. J. Strangeway. "Ion cyclotron waves near Io". Planetary and Space Science 49, nr 10-11 (sierpień 2001): 1125–36. http://dx.doi.org/10.1016/s0032-0633(01)00020-4.

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5

Russell, C. T., i D. E. Huddleston. "Ion-cyclotron waves at Io". Advances in Space Research 26, nr 10 (styczeń 2000): 1505–11. http://dx.doi.org/10.1016/s0273-1177(00)00090-9.

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6

Russell, C. T., H. Y. Wei, M. M. Cowee, F. M. Neubauer i M. K. Dougherty. "Ion cyclotron waves at Titan". Journal of Geophysical Research: Space Physics 121, nr 3 (marzec 2016): 2095–103. http://dx.doi.org/10.1002/2015ja022293.

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7

Narita, Y., E. Marsch, C. Perschke, K. H. Glassmeier, U. Motschmann i H. Comişel. "Wave–particle resonance condition test for ion-kinetic waves in the solar wind". Annales Geophysicae 34, nr 4 (7.04.2016): 393–98. http://dx.doi.org/10.5194/angeo-34-393-2016.

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Abstract. Conditions for the Landau and cyclotron resonances are tested for 543 waves (identified as local peaks in the energy spectra) in the magnetic field fluctuations of the solar wind measured by the Cluster spacecraft on a tetrahedral scale of 100 km. The resonance parameters are evaluated using the frequencies in the plasma rest frame, the parallel components of the wavevectors, the ion cyclotron frequency, and the ion thermal speed. The observed waves show a character of the sideband waves associated with the ion Bernstein mode, and are in a weak agreement with the fundamental electron cyclotron resonance in spite of the ion-kinetic scales. The electron cyclotron resonance is likely taking place in solar wind turbulence near 1 AU (astronomical unit).

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8

Thorne, R. M., i R. B. Horne. "Cyclotron absorption of ion-cyclotron waves at the bi-ion frequency". Geophysical Research Letters 20, nr 4 (19.02.1993): 317–20. http://dx.doi.org/10.1029/93gl00089.

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9

Sharma, Shatendra, i Jyotsna Sharma. "Spiraling ion beam driven electrostatic ion cyclotron wave instabilities in collisionless dusty plasma". International Journal of Modern Physics: Conference Series 32 (styczeń 2014): 1460352. http://dx.doi.org/10.1142/s2010194514603524.

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The numerical calculations of the growth rate in long parallel wavelength are made for a spiraling ion beam propagating through a collision less magnetized dusty plasma cylinder that drives electrostatic ion cyclotron waves to instability via cyclotron interaction. It is found that the growth rate of the instability of the electrostatic ion cyclotron waves increase in the long parallel limit with the density ratio of negatively charged dust grains to electrons. The growth rate of the unstable mode has the maximum value for the modes whose Eigen functions peak at the location of the beam and varies as the one-third power of the beam current in both the limits.

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10

Sharma, S. C., i V. K. Tripathi. "Excitation of ion-cyclotron waves by a spiralling ion beam in a plasma cylinder". Journal of Plasma Physics 50, nr 2 (październik 1993): 331–38. http://dx.doi.org/10.1017/s0022377800027112.

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A helical ion beam propagating through a plasma cylinder drives electrostatic ion-cyclotron waves to instability via cyclotron interaction. Higher harmonics of the beam cyclotron frequency can be generated in this way. The growth rate increases with the harmonic number. The efficiency of beam energy transfer to the wave can be of the order of a few per cent.

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11

Gary, S. Peter. "Low-frequency waves in a high-beta collisionless plasma: polarization, compressibility and helicity". Journal of Plasma Physics 35, nr 3 (czerwiec 1986): 431–47. http://dx.doi.org/10.1017/s0022377800011442.

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This paper considers the linear theory of waves near and below the ion cyclotron frequency in an isothermal electron-ion Vlasov plasma which is isotropic, homogeneous and magnetized. Numerical solutions of the full dispersion equation for the magnetosonic/whistler and Alfvén/ion cyclotron modes at βi = 1·0 are presented, and the polarizations, compressibilities, helicities, ion Alfvén ratios and ion cross-helicities are exhibited and compared. At sufficiently large βi and θ, the angle of propagation with respect to the magnetic field, the real part of the polarization of the Alfvén/ion cyclotron wave changes sign, so that, for such parameters, this mode is no longer left-hand polarized. The Alfvén/ion cyclotron mode becomes more compressive as the wavenumber ulereases, whereas the magnetosonic/whistler becomes more compressive with increasing θ, At oblique propagation, the helicity of both modes approaches zero in the long-wavelength limit; in contrast, the ion cross-helicity is of order unity for the Alfvén/ion cyclotron wave and decreases as θ increases for the magnetosonic/whistler mode.

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12

Kumar, Asheel, i V. K. Tripathi. "Excitation of ion Bernstein and ion cyclotron waves by a gyrating ion beam in a plasma column". Laser and Particle Beams 30, nr 1 (13.12.2011): 9–16. http://dx.doi.org/10.1017/s026303461100053x.

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AbstractGyrating ion beams, produced by quick ionization of neutral beams, employed for plasma heating, are susceptible to ion Bernstein and ion cyclotron instabilities. The Bernstein wave, having large parallel phase velocity, is excited via cyclotron interaction whereas the ion cyclotron wave with lower parallel phase velocity could be driven by Cerenkov interaction as well. The maximally growing modes have transverse wave number of the order of inverse ion Larmor radius. The nonlocal effects cause reduction in the growth rate.

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13

Bogdanov, A. T., K. H. Glassmeier, G. Musmann, M. K. Dougherty, S. Kellock, P. Slootweg i B. Tsurutani. "Ion cyclotron waves in the Earth’s magnetotail during CASSINI’s Earth swing-by". Annales Geophysicae 21, nr 10 (31.10.2003): 2043–57. http://dx.doi.org/10.5194/angeo-21-2043-2003.

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Abstract. The properties of low frequency magnetotail waves observed during CASSINI’s Earth swing-by are examined. A maximum in the distribution of the waves about half the proton cyclotron frequency and a peak at linear polarisation are found and their implications are analysed in detail. Data on the fluid plasma velocity for the observation interval are not available and thus no unique conclusions about Doppler shift influence on the properties of the waves can be made. This determines the need to analyse different hypotheses in order to understand the origin of the waves. The plausibility of competing interpretations, such as off-resonance proton cyclotron waves and bi-ion cyclotron waves at the gyrofrequency of a heavy ion component of the magneto-tail plasma in the form of He ++ ions of solar wind origin is questioned.Key words. Space plasma physics (waves and instabilities) – Magnetospheric physics (plasma waves and instabilities; magnetotail)

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14

KATO, Yoshio, i Yutaka TONEGAWA. "Ion cyclotron waves associated with substorm." Proceedings of the Japan Academy. Ser. B: Physical and Biological Sciences 65, nr 4 (1989): 57–59. http://dx.doi.org/10.2183/pjab.65.57.

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15

Nykyri, K., B. Grison, P. J. Cargill, B. Lavraud, E. Lucek, I. Dandouras, A. Balogh, N. Cornilleau-Wehrlin i H. Rème. "Origin of the turbulent spectra in the high-altitude cusp: Cluster spacecraft observations". Annales Geophysicae 24, nr 3 (19.05.2006): 1057–75. http://dx.doi.org/10.5194/angeo-24-1057-2006.

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Abstract. High-resolution magnetic field data from Cluster Flux Gate Magnetometer (FGM) and the Spatio-Temporal Analysis of Field Fluctuations (STAFF) instruments are used to study turbulent magnetic field fluctuations during the high-altitude cusp crossing on 17 March 2001. Despite the quiet solar wind conditions, the cusp was filled with magnetic field turbulence whose power correlates with the field-aligned ion plasma flux. The magnetic field wave spectra shows power law behavior with both double and single slopes with break in the spectra usually occurring in the vicinity of the local ion cyclotron frequency. Strong peaks in the wave power close to local ion cyclotron frequency were sometimes observed, with secondary peaks at higher harmonics indicative of resonant processes between protons and the waves. We show that the observed spectral break point may be caused partly by damping of obliquely propagating kinetic Alfvén (KAW) waves and partly by cyclotron damping of ion cyclotron waves.

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16

Crocker, N. A., S. X. Tang, K. E. Thome, J. B. Lestz, E. V. Belova, A. Zalzali, R. O. Dendy i in. "Novel internal measurements of ion cyclotron frequency range fast-ion driven modes". Nuclear Fusion 62, nr 2 (5.01.2022): 026023. http://dx.doi.org/10.1088/1741-4326/ac3d6a.

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Abstract Novel internal measurements and analysis of ion cyclotron frequency range fast-ion driven modes in DIII-D are presented. Observations, including internal density fluctuation ( n ~ ) measurements obtained via Doppler backscattering, are presented for modes at low harmonics of the ion cyclotron frequency localized in the edge. The measurements indicate that these waves, identified as coherent ion cyclotron emission (ICE), have high wave number, k ⊥ ρ fast ≳ 1, consistent with the cyclotron harmonic wave branch of the magnetoacoustic cyclotron instability, or electrostatic instability mechanisms. Measurements show extended spatial structure (at least ∼1/6 the minor radius). These edge ICE modes undergo amplitude modulation correlated with edge localized modes (ELM) that is qualitatively consistent with expectations for ELM-induced fast-ion transport.

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17

Luo, Qiaowen, Xingyu Zhu, Jiansen He, Jun Cui, Hairong Lai, Daniel Verscharen i Die Duan. "Coherence of Ion Cyclotron Resonance in Damped Ion Cyclotron Waves in Space Plasmas". Astrophysical Journal 928, nr 1 (1.03.2022): 36. http://dx.doi.org/10.3847/1538-4357/ac52a9.

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Abstract Ion cyclotron resonance is one of the fundamental energy-conversion processes through field–particle interaction in collisionless plasmas. However, the key evidence for ion cyclotron resonance (i.e., the coherence between electromagnetic fields and the ion phase-space density) and the resulting damping of ion cyclotron waves (ICWs) has not yet been directly observed. Investigating the high-quality measurements of space plasmas by the Magnetospheric Multiscale (MMS) satellites, we find that both the wave electromagnetic field vectors and the bulk velocity of the disturbed ion velocity distribution rotate around the background magnetic field. Moreover, we find that the absolute gyrophase angle difference between the center of the fluctuations in the ion velocity distribution functions and the wave electric field vectors falls in the range of (0, 90)°, consistent with an ongoing energy conversion from wave fields to particles. By invoking plasma kinetic theory, we demonstrate that the field–particle correlation for the damped ICWs in our theoretical model matches well with our observations. Furthermore, the wave electric field vectors ( δ E wave , ⊥ ′ ), ion current density (δ J i,⊥), and energy transfer rate ( δ J i , ⊥ · δ E wave , ⊥ ′ ) exhibit quasiperiodic oscillations, and the integrated work done by the electromagnetic field on the ions is positive, indicating that ions are mainly energized by the perpendicular component of the electric field via cyclotron resonance. Therefore, our combined analysis of MMS observations and kinetic theory provides direct, thorough, and comprehensive evidence for ICW damping in space plasmas.

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18

Cremer, M., i M. Scholer. "On a nonlinear state of the electromagnetic ion/ion cyclotron instability". Nonlinear Processes in Geophysics 7, nr 3/4 (31.12.2000): 173–77. http://dx.doi.org/10.5194/npg-7-173-2000.

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Abstract. We have investigated the nonlinear properties of the electromagnetic ion/ion cyclotron instability (EMIIC) by means of hybrid simulations (macroparticle ions, massless electron fluid). The instability is driven by the relative (super-Alfvénic) streaming of two field-aligned ion beams in a low beta plasma (ion thermal pressure to magnetic field pressure) and may be of importance in the plasma sheet boundary layer. As shown in previously reported simulations the waves propagate obliquely to the magnetic field and heat the ions in the perpendicular direction as the relative beam velocity decreases. By running the simulation to large times it can be shown that the large temperature anisotropy leads to the ion cyclotron instability (IC) with parallel propagating Alfvén ion cyclotron waves. This is confirmed by numerically solving the electromagnetic dispersion relation. An application of this property to the plasma sheet boundary layer is discussed.

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19

T Ball, Lewis. "Heavy Ion Acceleration by Double-cyclotron Absorption: Some Analytic Approximations". Australian Journal of Physics 42, nr 5 (1989): 493. http://dx.doi.org/10.1071/ph890493.

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possible to accelerate heavy ions in a magnetised plasma via a process where an ion simultaneously absorbs two gyromagnetic waves whose frequencies sum to the ion gyrofrequency. Analytic approximations to the probability of such double-cyclotron absorption are derived. A particularly simple approximation is presented for the special case where the waves all have frequencies very close to half the ion gyrofrequency. The rate of perpendicular acceleration of the ions due to double-cyclotron absorption is considered, and a simple analytic expression is derived for the case here the waves have the quasimonochromatic distribution mentioned above. One possible application of these proximatio.ns is to investigate the proposal that perpendicular acceleration of oxygen (0+) ions in the Earth's magnetosphere, due to double-cyclotron absorption, may give rise to O+-conic distributions

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20

Reddy, R. V., G. S. Lakhina, N. Singh i R. Bharuthram. "Spiky parallel electrostatic ion cyclotron and ion acoustic waves". Nonlinear Processes in Geophysics 9, nr 1 (28.02.2002): 25–29. http://dx.doi.org/10.5194/npg-9-25-2002.

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Abstract. One of the interesting observations from the FAST satellite is the detection of strong spiky waveforms in the parallel electric field in association with ion cyclotron oscillations in the perpendicular electric fields. We report here an analytical model of the coupled nonlinear ion cyclotron and ion-acoustic waves, which could explain the observations. Using the fluid equations for the plasma consisting of warm electrons and cold ions, a nonlinear wave equation is derived in the rest frame of the propagating wave for any direction of propagation oblique to the ambient magnetic field. The equilibrium bulk flow of ions is also included in the model to mimic the field-aligned current. Depending on the wave Mach number M defined by M = V/Cs with V and Cs being the wave phase velocity and ion-acoustic speed, respectively, we find a range of solutions varying from a sinusoidal wave form for small amplitudes and low M to sawtooth and highly spiky waveforms for nearly parallel propagation. The results from the model are compared with the satellite observations.

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21

Volwerk, M., C. Koenders, M. Delva, I. Richter, K. Schwingenschuh, M. S. Bentley i K. H. Glassmeier. "Ion cyclotron waves during the Rosetta approach phase: a magnetic estimate of cometary outgassing". Annales Geophysicae 31, nr 12 (17.12.2013): 2201–6. http://dx.doi.org/10.5194/angeo-31-2201-2013.

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Abstract. A theoretical model for the ion cyclotron wave generation during the approach phase of Rosetta to 67P/Churyumov–Gerasimenko is presented. For various activity levels of the comet, the crossing of the observational threshold is determined, whose level is derived from the wave power in the undisturbed solar wind near the comet's location during the approach phase at the appropriate frequency. The Giotto flyby at 27P/Grigg–Skjellerup is used to obtain an estimate of how often water-group ion cyclotron waves are observed, and to get insight into the wave forms. At 67P/Churyumov–Gerasimenko one can expect to observe water-group ion cyclotron waves already at a distance of 600 000 km from the nucleus for a nominal outgassing rate of Q = 350 × 1023 molecules per second. The observed first location of cyclotron waves during the Rosetta approach phase will give an indication of the actual outgassing rate of the comet.

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22

SHUKLA, P. K., i A. A. MAMUN. "Low-frequency electrostatic waves in a bounded dusty magnetoplasma". Journal of Plasma Physics 65, nr 2 (luty 2001): 97–105. http://dx.doi.org/10.1017/s0022377801008698.

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A rigorous theoretical investigation is made of obliquely propagating low-frequency electrostatic waves in a cylindrically bounded magnetized dusty plasma. A number of different modes, such as modified convective cells, coupled ion-cyclotron and dust-ion-acoustic waves, modified lower-hybrid waves, coupled dust-cyclotron and dust-acoustic waves, etc., are investigated. It is shown that the effects of the cylindrical boundary of the dusty plasma system, the external magnetic field, and the obliqueness (of the propagating modes) significantly modify the dispersion properties of these different low-frequency electrostatic waves. The implications of our results for laboratory dusty magnetoplasmas are briefly pointed out.

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23

SORASIO, G., i M. ROSENBERG. "Instability of higher-harmonic electrostatic dust cyclotron waves". Journal of Plasma Physics 65, nr 4 (maj 2001): 319–29. http://dx.doi.org/10.1017/s0022377801001118.

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Conditions for exciting higher-harmonic electrostatic dust cyclotron waves in a collisional dusty plasma are investigated. Linear kinetic theory is used, and the effects of neutral–charged particle collisions are taken into account. In a plasma with negatively charged dust, electrostatic dust cyclotron waves can be driven unstable by ions drifting along the magnetic field. It is found that, under certain conditions, the critical ion drift for the excitation of higher-harmonic electrostatic dust cyclotron waves (i.e., ω ∼ mΩd, where m [ges ] 2 and Ωd is the dust cyclotron frequency) can be comparable to the critical drift for the excitation of the fundamental cyclotron harmonic (i.e., ω ∼ Ωd). Stability conditions are investigated for ranges of parameters that may be relevant to laboratory dusty plasmas.

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24

Rönnmark, Kjell, i Mats André. "Convection of ion cyclotron waves to ion-heating regions". Journal of Geophysical Research 96, A10 (1991): 17573. http://dx.doi.org/10.1029/91ja01793.

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25

Dolla, L., i J. Solomon. "Solar off-limb line widths with SUMER: revised value of the non-thermal velocity and new results". Annales Geophysicae 27, nr 9 (25.09.2009): 3551–58. http://dx.doi.org/10.5194/angeo-27-3551-2009.

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Abstract. Alfvén waves and ion-cyclotron absorption of high-frequency waves are frequently brought into models devoted to coronal heating and fast solar-wind acceleration. Signatures of ion-cyclotron resonance have already been observed in situ in the solar wind and in the upper corona. In the lower corona, one can use the line profiles to infer the ion temperatures. But the value of the so-called "non-thermal" (or "unresolved") velocity, potentially related to the amplitude of Alfvén waves propagating in the corona, is critical in firmly identifying ion-cyclotron preferential heating. In a previous paper, we proposed a method to constrain both the Alfvén wave amplitude and the preferential heating, above a polar coronal hole observed with the SUMER/SOHO spectrometer. Taking into account the effect of instrumental stray light before analysing the line profiles, we ruled out any direct evidence of damping of the Alfvén waves and showed that ions with the lowest charge-to-mass ratios were preferentially heated. We re-analyse these data here to correct the derived non-thermal velocity, and we discuss the consequences on the main results. We also include a measure of the Fe VIII 1442.56 Å line width (second order), thus extending the charge-to-mass ratio domain towards ions more likely to experience cyclotron resonance.

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26

Boardsen, S. A., D. A. Gurnett i W. K. Peterson. "Double-peaked electrostatic ion cyclotron harmonic waves". Journal of Geophysical Research 95, A7 (1990): 10591. http://dx.doi.org/10.1029/ja095ia07p10591.

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27

Doğan, S., i E. R. Pekünlü. "Ion-cyclotron waves in solar coronal hole". New Astronomy 17, nr 3 (kwiecień 2012): 316–24. http://dx.doi.org/10.1016/j.newast.2011.08.008.

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28

Russell, C. T., X. Blanco-Cano i M. G. Kivelson. "Ion cyclotron waves in Io's wake region". Planetary and Space Science 51, nr 3 (marzec 2003): 233–38. http://dx.doi.org/10.1016/s0032-0633(02)00198-8.

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29

Dougherty, M. K., D. J. Southwood i A. Lachin. "Ion cyclotron waves in the Jovian magnetosphere". Advances in Space Research 20, nr 2 (styczeń 1997): 215–19. http://dx.doi.org/10.1016/s0273-1177(97)00536-x.

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30

Fraser, B. J., J. C. Samson, R. L. McPherron i C. T. Russell. "Ion cyclotron waves observed near the plasmapause". Advances in Space Research 6, nr 3 (1986): 223–26. http://dx.doi.org/10.1016/0273-1177(86)90336-4.

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31

Bortnik, J., N. Omidi, L. Chen, R. M. Thorne i R. B. Horne. "Saturation characteristics of electromagnetic ion cyclotron waves". Journal of Geophysical Research: Space Physics 116, A9 (wrzesień 2011): n/a. http://dx.doi.org/10.1029/2011ja016638.

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32

Bräysy, T., i K. Mursula. "Conjugate observations of electromagnetic ion cyclotron waves". Journal of Geophysical Research: Space Physics 106, A4 (1.04.2001): 6029–41. http://dx.doi.org/10.1029/2000ja003009.

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33

Silin, I., R. D. Sydora, I. R. Mann, K. Sauer i R. L. Mace. "Nonlinear evolution of electromagnetic ion cyclotron waves". Physics of Plasmas 18, nr 4 (kwiecień 2011): 042108. http://dx.doi.org/10.1063/1.3571598.

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34

Brodin, G., i L. Stenflo. "Coupling Coefficients for Ion-Cyclotron Alfvén Waves". Contributions to Plasma Physics 30, nr 3 (1990): 413–19. http://dx.doi.org/10.1002/ctpp.2150300308.

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35

Bahcivan, H., i R. Cosgrove. "Enhanced ion acoustic lines due to strong ion cyclotron wave fields". Annales Geophysicae 26, nr 8 (31.07.2008): 2081–95. http://dx.doi.org/10.5194/angeo-26-2081-2008.

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Abstract. The Fast Auroral Snapshot Explorer (FAST) satellite detected intense and coherent 5–20 m electric field structures in the high-latitude topside auroral ionosphere between the altitudes of 350 km and 650 km. These electric fields appear to belong to electrostatic ion cyclotron (EIC) waves in terms of their frequency and wavelengths. Numerical simulations of the response of an electron plasma to the parallel components of these fields show that the waves are likely to excite a wave-driven parallel ion acoustic (IA) instability, through the creation of a highly non-Maxwellian electron distribution function, which when combined with the (assumed) Maxwellian ion distribution function provides inverse Landau damping. Because the counter-streaming threshold for excitation of EIC waves is well below that for excitation of IA waves (assuming Maxwellian statistics) our results suggest a possible two step mechanism for destabilization of IA waves. Combining this simulation result with the observational fact that these EIC waves share a common phenomenology with the naturally enhanced IA lines (NEIALS) observed by incoherent scatter radars, especially that they both occur near field-aligned currents, leads to the proposition that this two-step mechanism is an alternative path to NEIALS.

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36

Wessen, K. P., i N. F. Cramer. "Finite-frequency surface waves on current sheets". Journal of Plasma Physics 45, nr 3 (czerwiec 1991): 389–406. http://dx.doi.org/10.1017/s0022377800015798.

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The dispersion relation for low-frequency surface waves at a current sheet between two magnetized plasmas is derived using the cold-plasma dielectric tensor with finite ion-cyclotron frequency. The magnetic field direction is allowed to change discontinuously across the sheet, but the plasma density remains constant. The cyclotron frequency causes a splitting of the dispersion relation into a number of mode branches with frequencies both less than and greater than the ion-cyclotron frequency. The existence of these modes depends in particular upon the degree of magnetic field discontinuity and the direction of wave propagation in the sheet relative to the magnetic field directions. Sometimes two modes can exist for the same direction of propagation. The existence of modes undamped by Alfvén resonance absorption is predicted. Analytical solutions are obtained in the low-frequency and magnetic-field-reversal limits. The solutions are obtained numerically in the general case.

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37

Long, Minyi, Xing Cao, Xudong Gu, Binbin Ni, Shaojie Qu, Shengyi Ye, Zhonghua Yao, Siyuan Wu i Yan Xu. "Statistics of Water-group Band Ion Cyclotron Waves in Saturn's Inner Magnetosphere Based on 13 yr of Cassini Measurements". Astrophysical Journal 932, nr 1 (1.06.2022): 56. http://dx.doi.org/10.3847/1538-4357/ac6bf0.

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Abstract Based on Cassini observations from 2004 to 2016, we perform a comprehensive analysis of the statistical distribution of the occurrence rate, averaged amplitude, wave normal angle (WNA), ellipticity, and power spectral intensity of ion cyclotron waves in Saturn's inner magnetosphere. Our results show that ion cyclotron waves mainly occur between the orbits of Enceladus and Dione near the equatorial region (∣λ∣ < 20°), with higher occurrence rates in the northern hemisphere than the southern hemisphere. The averaged wave amplitudes vary between 0.1 and 2 nT with a strong day–night asymmetry and a pronounced minimum at the equator. Saturnian ion cyclotron waves are predominantly left-handed polarized with small WNAs near the equator and become linearly polarized with larger WNAs at higher latitudes. The major wave power occurs frequently at frequencies of 0.5–1.2 f w + , where f w + is the equatorial gyrofrequency of H2O+ ions, with the strongest intensity (>∼10 nT2 Hz−1) at L ∼ 6.5 statistically present in the midnight sector.

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38

Terasaka, K., i S. Yoshimura. "Plasma–neutral coupling allows electrostatic ion cyclotron waves to propagate below ion cyclotron frequency". Physics of Plasmas 29, nr 2 (luty 2022): 022103. http://dx.doi.org/10.1063/5.0078192.

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Mousavi, Ameneh, Kaijun Liu i Sina Sadeghzadeh. "Particle-in-cell simulations of high-frequency waves driven by pickup ion ring-beam distributions in the outer heliosheath". Monthly Notices of the Royal Astronomical Society 512, nr 3 (21.03.2022): 4291–97. http://dx.doi.org/10.1093/mnras/stac748.

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ABSTRACT Scattering of pickup ion ring-beam distributions in the outer heliosheath is a fundamental element in the spatial retention scenario of the energetic neutral atom (ENA) ribbon observed by the Interstellar Boundary EXplorer (IBEX). According to our earlier linear instability analysis, pickup ion ring-beam distributions trigger magnetic field-aligned, right-hand polarized unstable waves in two separate frequency ranges which are near and far above the proton cyclotron frequency, respectively. We have performed hybrid simulations to study the unstable waves near the proton cyclotron frequency. However, the high-frequency waves well above the proton cyclotron frequency are beyond the reach of hybrid simulations. In this paper, particle-in-cell simulations are carried out to study the parallel- and antiparallel-propagating high-frequency waves excited by the outer heliosheath pickup ions at different pickup angles as well as the scattering of the pickup ions by the waves excited. In the early stages of the simulations, the results confirm the excitation of the parallel-propagating, right-hand polarized high-frequency waves as predicted by the earlier linear analysis. Later in the simulations, enhanced antiparallel-propagating modes also emerge. Furthermore, the evolution of the pickup ion ring-beam distributions of the selected pickup angles reveals that the high-frequency waves do not significantly contribute to the pickup ion scattering. These results are favourable regarding the plausibility of the spatial retention scenario of the IBEX ENA ribbon.

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40

Kitamura, N., M. Kitahara, M. Shoji, Y. Miyoshi, H. Hasegawa, S. Nakamura, Y. Katoh i in. "Direct measurements of two-way wave-particle energy transfer in a collisionless space plasma". Science 361, nr 6406 (6.09.2018): 1000–1003. http://dx.doi.org/10.1126/science.aap8730.

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Particle acceleration by plasma waves and spontaneous wave generation are fundamental energy and momentum exchange processes in collisionless plasmas. Such wave-particle interactions occur ubiquitously in space. We present ultrafast measurements in Earth’s magnetosphere by the Magnetospheric Multiscale spacecraft that enabled quantitative evaluation of energy transfer in interactions associated with electromagnetic ion cyclotron waves. The observed ion distributions are not symmetric around the magnetic field direction but are in phase with the plasma wave fields. The wave-ion phase relations demonstrate that a cyclotron resonance transferred energy from hot protons to waves, which in turn nonresonantly accelerated cold He+ to energies up to ~2 kilo–electron volts. These observations provide direct quantitative evidence for collisionless energy transfer in plasmas between distinct particle populations via wave-particle interactions.

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41

MCKENZIE, J. F., i Q. HU. "Interaction of positive and negative energy waves in a magnetized bi-ion plasma with differential ion streaming". Journal of Plasma Physics 74, nr 3 (czerwiec 2008): 345–52. http://dx.doi.org/10.1017/s0022377807006770.

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AbstractIn this paper the concept of negative energy waves facilitates the analysis of instability in a magnetized bi-ion plasma with differential ion streaming. There are three frequency regimes in which instability may arise. For frequencies less than the alpha particle gyrofrequency, a negative energy alpha ion-cyclotron mode can interact with a positive energy proton-cyclotron mode. In the intermediate frequency regime lying between the alpha and proton gyrofrequencies, a negative energy alpha-acoustic mode interacts with a positive energy proton-cyclotron mode. In the high-frequency regime above the proton-cyclotron frequency a negative energy alpha-acoustic mode interacts with a positive energy proton-acoustic mode. The resonance (or coalescence) condition which lends itself to a simple geometrical interpretation as the intersection between the proton and alpha mode wave normal diagrams with differential streaming permits the evaluation of the instability growth rate in each frequency regime, which is calculated for both subsonic and supersonic differential streaming.

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42

Shi, Zhaodong, Patricio A. Muñoz, Jörg Büchner i Siming Liu. "Proton and Helium Heating by Cascading Turbulence in a Low-beta Plasma". Astrophysical Journal 941, nr 1 (1.12.2022): 39. http://dx.doi.org/10.3847/1538-4357/ac9fd7.

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Abstract How ions are energized and heated is a fundamental problem in the study of energy dissipation in magnetized plasmas. In particular, the heating of heavy ions (including 4He2+, 3He2+, and others) has been a constant concern for understanding the microphysics of impulsive solar flares. In this article, via two-dimensional hybrid-kinetic particle-in-cell simulations, we study the heating of helium ions (4He2+) by turbulence driven by cascading waves launched at large scales from the left-handed polarized helium ion cyclotron wave branch of a multi-ion plasma composed of electrons, protons, and helium ions. We find significant parallel (to the background magnetic field) heating for both helium ions and protons due to the formation of beams and plateaus in their velocity distribution functions along the background magnetic field. The heating of helium ions in the direction perpendicular to the magnetic field starts with a lower rate than that in the parallel direction, but overtakes the parallel heating after a few hundreds of the proton gyro-periods due to cyclotron resonances with mainly obliquely propagating waves induced by the cascade of injected helium ion cyclotron waves at large scales. There is, however, little evidence for proton heating in the perpendicular direction due to the absence of left-handed polarized cyclotron waves near the proton cyclotron frequency. Our results are useful for understanding the preferential heating of 3He and other heavy ions in the 3He-rich solar energetic particle events, in which helium ions play a crucial role as a species of background ions regulating the kinetic plasma behavior.

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Shaposhnikov, V. E., G. V. Litvinenko, V. V. Zaitsev, V. V. Zakharenko i A. A. Konovalenko. "Origin of the zebra structure in the Jovian decameter radio emission". Astronomy & Astrophysics 645 (23.12.2020): A31. http://dx.doi.org/10.1051/0004-6361/202039304.

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Context. We discuss the origin of quasi-harmonic emission bands that have been observed in the dynamic spectra of the Jovian decameter emission. Aims. We aim to show that the interpretation of the observed structure can be based on the effect of double plasma resonance (DPR) at ion cyclotron harmonics. Methods. According to the proposed model, in the extended source in the upper ionosphere of Jupiter, where the DPR condition is satisfied for one of the ion cyclotron frequency harmonics, the ion cyclotron waves are effectively excited at the frequency of the lower hybrid resonance. The observed electromagnetic radiation with a quasi-harmonic structure arises due to scattering of ion cyclotron waves by supra-thermal electrons. Results. Based on the VIP4 magnetic field model, we determine the longitudes at which the source of the considered radiation can be located. The obtained estimates of the plasma density and its height distribution in the source, as well as the energies of emitting ions and scattering electrons provide information about the plasma parameters in the upper ionosphere of Jupiter. Furthermore, these estimates are in good agreement with the observational data.

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Milić, B. S. "Excitation of long-wave quasi-perpendicular electrostatic ion-cyclotron waves in multi-species weakly ionized plasmas". Journal of Plasma Physics 43, nr 1 (luty 1990): 23–50. http://dx.doi.org/10.1017/s0022377800014604.

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It is shown, using kinetic equations with BGK model collision integrals, that in a multi-species weakly ionized plasma the quasi-perpendicular ion-cyclotron instability (waves of growing amplitude) excited by the electron drift parallel to the background magnetic field first sets in for long waves (modal wavelengths much larger than the electron mean free path) as the drift is gradually increased, much as in plasmas with only one ion species. Only waves with modal frequencies close to some cyclotron harmonics of some of the ion species present are taken into account in the present work. Owing to the mutual commensurability of all the ion-cyclotron frequencies, more than one species of ions may be ‘resonant’ with any mode of the type considered. The role of ‘resonant’ and ‘non-resonant’ ion species is investigated, both in general and for some particular plasmas. Some numerical details are also given. It is shown that although in most instances the threshold drifts vary monotonically (but not linearly) as the plasma composition is varied, there are cases in which maxima or minima (often depending on the degree of non-isothermality) of the threshold drift magnitude are predicted for some specific plasma compositions. These are usually encountered in plasmas containing ions with different charge numbers.

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45

Suszcynsky, D. M., R. L. Merlino i N. D'Angelo. "Electrostatic ion-cyclotron waves in a two-ion component plasma". IEEE Transactions on Plasma Science 16, nr 3 (czerwiec 1988): 396–98. http://dx.doi.org/10.1109/27.3849.

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EL MEKKI, O. M. "Over-reflection of magnetoacoustic ion-cyclotron plasma waves". Journal of Plasma Physics 59, nr 1 (styczeń 1998): 1–14. http://dx.doi.org/10.1017/s0022377897006247.

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The over-reflection of magnetoacoustic ion-cyclotron waves in a warm Hall plasma is investigated. It is shown that the effect of the Hall term is to strongly support over-reflection, thereby destabilizing the flow. Its relevance to the current-vortex sheet of the magnetosheath resulting from the interaction of the solar wind and the Earth's magnetopause is pointed out.

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ZHANG, T. X. "Anisotropic model for resonant heating of ions by Alfvén waves". Journal of Plasma Physics 79, nr 5 (9.08.2013): 963–71. http://dx.doi.org/10.1017/s0022377813000871.

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AbstractAnisotropic heating of ions by Alfvén waves with frequency in the ion–cyclotron frequency range and propagation parallel to the magnetic field lines is investigated. First, particle–Alfvén wave interactions are quasilinearly examined from the kinetic theory in a hot multi-ion-magnetized plasma. As a result, the parallel and perpendicular heating rates of ions are derived analytically. Then, in terms of this anisotropic heating model and the dispersion relation of magnetic field-aligned left-hand polarized electromagnetic ion–cyclotron–Alfvén (EMICA) waves, the resonant heating of H, 2H, 3H, 3He, and 4He ions in a typical preheated laboratory plasma is numerically studied. It is shown that the EMICA waves can efficiently heat ions through cyclotron resonances primarily in the perpendicular direction. The perpendicular temperatures of H, 2H, 3H, 3He, and 4He increase much faster than the parallel ones. In comparison with the result from the previously developed isotropic heating model, the parallel heating by the EMICA waves is about much weaker, while the perpendicular heating is more efficient. Parameters such as density, temperature, magnetic field, wave-energy density, and ion species can affect the efficiency of the Alfvén wave heating in a similar way as shown in the isotropic heating model. The anisotropic model can be applied to explain the measurements of why O+5 and Mg+9 are heated extreme perpendicularly in solar coronal holes.

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Telloni, Daniele, Gary P. Zank, Laxman Adhikari, Lingling Zhao, Roberto Susino, Ester Antonucci, Silvano Fineschi i in. "Does Turbulence along the Coronal Current Sheet Drive Ion Cyclotron Waves?" Astrophysical Journal 944, nr 2 (1.02.2023): 227. http://dx.doi.org/10.3847/1538-4357/acb693.

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Abstract Evidence for the presence of ion cyclotron waves (ICWs), driven by turbulence, at the boundaries of the current sheet is reported in this paper. By exploiting the full potential of the joint observations performed by Parker Solar Probe and the Metis coronagraph on board Solar Orbiter, local measurements of the solar wind can be linked with the large-scale structures of the solar corona. The results suggest that the dynamics of the current sheet layers generates turbulence, which in turn creates a sufficiently strong temperature anisotropy to make the solar-wind plasma unstable to anisotropy-driven instabilities such as the Alfvén ion cyclotron, mirror-mode, and firehose instabilities. The study of the polarization state of high-frequency magnetic fluctuations reveals that ICWs are indeed present along the current sheet, thus linking the magnetic topology of the remotely imaged coronal source regions with the wave bursts observed in situ. The present results may allow improvement of state-of-the-art models based on the ion cyclotron mechanism, providing new insights into the processes involved in coronal heating.

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KATO, Yoshio, i Yutaka TONEGAWA. "Ion Cyclotron Waves Associated with ssc and si." Proceedings of the Japan Academy. Ser. B: Physical and Biological Sciences 68, nr 4 (1992): 37–40. http://dx.doi.org/10.2183/pjab.68.37.

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Shukla, P. K., i L. Stenflo. "Nonlinear propagation of electromagnetic ion-cyclotron Alfvén waves". Physics of Fluids 28, nr 5 (1985): 1576. http://dx.doi.org/10.1063/1.864946.

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