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Littérature scientifique sur le sujet « Electromagnetic ion temperature »

Auteur : Grafiati

Publié le 6 septembre 2023

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Articles de revues sur le sujet "Electromagnetic ion temperature"

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SHUKLA, NITIN, A. STOCKEM, F. FIÚZA et L. O. SILVA. « Enhancement in the electromagnetic beam-plasma instability due to ion streaming ». Journal of Plasma Physics 78, n^o 2 (16 décembre 2011) : 181–87. http://dx.doi.org/10.1017/s0022377811000559.

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AbstractWe investigate the Weibel instability in counter-propagating electron–ion plasmas with focus on the ion contribution, considering a realistic mass ratio. A generalized dispersion relation is derived from the relativistic theory by assuming an initially anisotropic temperature, which is represented by a waterbag distribution in momentum space, which shows an enhanced growth rate due to ion response. Two-dimensional particle-in-cell simulations support the theoretical analysis, showing a further amplification of magnetic field on ion time scale. The effect of an initial anisotropic temperature is investigated showing that the growth rate is monotonously decreased if the transverse spread is increased. Nevertheless, the presence of ions generates that the instability can develop for significantly higher electron temperatures. Suppression of oblique mode is also explored by introducing a parallel velocity spread.

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Kim, J. Y., W. Horton et J. Q. Dong. « Electromagnetic effect on the toroidal ion temperature gradient mode ». Physics of Fluids B : Plasma Physics 5, n^o 11 (novembre 1993) : 4030–39. http://dx.doi.org/10.1063/1.860623.

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Chong, T. H., M. Fukuda, T. Yorita, H. Kanda, Y. Yasuda, H. W. Koay, Y. Morita et al. « Development of ECR ion source with high-temperature superconducting REBCO coils ». Journal of Physics : Conference Series 2244, n^o 1 (1 avril 2022) : 012108. http://dx.doi.org/10.1088/1742-6596/2244/1/012108.

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Abstract A new High-Temperature Superconducting ECR (HTS-ECR) ion source is under development in Research Center for Nuclear Physics (RCNP), Osaka University. This ion source will be used for production of high intensity proton, deuteron and He ion beams. The HTS-ECR magnets are composed of three solenoid coils and a set of sextupole coils made of REBCO tapes, a high-temperature superconductor. The HTS-ECR ion source is designed to operate at frequency of 2.45 GHz and 10 GHz. Performance test of the HTS coils had been carried out at 31 K and 77 K. This HTS coil technology will be applied to development of a meter-size HTS coil system of a high intensity compact AVF cyclotron. This paper introduces the basic design of the HTS-ECR ion source. The performance test results showed that REBCO solenoids remain superconducting state with a current up to 400 A. Simulation results of the magnetic field and electromagnetic field distributions in a plasma chamber fulfilled the requirements of electron cyclotron resonance conditions at 2.45 GHz and 10 GHz. Simulation result of mirror ratios and electromagnetic field amplitudes are also presented in this paper.

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Barghouthi, I. A., N. M. Doudin, A. A. Saleh et V. Pierrard. « High-altitude and high-latitude O<sup>+</sup> ; and H<sup>+</sup> ; outflows : the effect of finite electromagnetic turbulence wavelength ». Annales Geophysicae 25, n^o 10 (6 novembre 2007) : 2195–202. http://dx.doi.org/10.5194/angeo-25-2195-2007.

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Abstract. The energization of ions, due to interaction with electromagnetic turbulence (i.e. wave-particle interactions), has an important influence on H+ and O+ ions outflows in the polar region. The effects of altitude and velocity dependent wave-particle interaction on H+ and O+ ions outflows in the auroral region were investigated by using Monte Carlo method. The Monte Carlo simulation included the effects of altitude and velocity dependent wave-particle interaction, gravity, polarization electrostatic field, and divergence of auroral geomagnetic field within the simulation tube (1.2–10 earth radii, RE). As the ions are heated due to wave-particle interactions (i.e. ion interactions with electromagnetic turbulence) and move to higher altitudes, the ion gyroradius ρi may become comparable to the electromagnetic turbulence wavelength λ⊥ and consequently (k⊥ρi) becomes larger than unity. This turns the heating rate to be negligible and the motion of the ions is described by using Liouville theorem. The main conclusions are as follows: (1) the formation of H+ and O+ conics at lower altitudes and for all values of λ⊥; (2) O+ toroids appear at 3.72 RE, 2.76 RE and 2 RE, for λ⊥=100, 10, and 1 km, respectively; however, H+ toroids appear at 6.6 RE, 4.4 RE and 3 RE, for λ⊥=100, 10, and 1 km, respectively; and H+ and O+ ion toroids did not appear for the case λ⊥ goes to infinity, i.e. when the effect of velocity dependent wave-particle interaction was not included; (3) As λ⊥ decreases, H+ and O+ ion drift velocity decreases, H+ and O+ ion density increases, H+ and O+ ion perpendicular temperature and H+ and O+ ion parallel temperature decrease; (4) Finally, including the effect of finite electromagnetic turbulence wavelength, i.e. the effect of velocity dependent diffusion coefficient and consequently, the velocity dependent wave-particle interactions produce realistic H+ and O+ ion temperatures and H+ and O+ toroids, and this is, qualitatively, consistent with the observations of H+ and O+ ions in the auroral region at high altitudes.

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Cremer, M., et M. Scholer. « On a nonlinear state of the electromagnetic ion/ion cyclotron instability ». Nonlinear Processes in Geophysics 7, n^o 3/4 (31 décembre 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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Weiland, J., et A. Hirose. « Electromagnetic and kinetic effects on the ion temperature gradient mode ». Nuclear Fusion 32, n^o 1 (janvier 1992) : 151–55. http://dx.doi.org/10.1088/0029-5515/32/1/i13.

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Peng, Shuitao, Lu Wang et Yuan Pan. « Intrinsic parallel rotation drive by electromagnetic ion temperature gradient turbulence ». Nuclear Fusion 57, n^o 3 (12 décembre 2016) : 036003. http://dx.doi.org/10.1088/1741-4326/aa4e57.

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Lashmore-Davies, C. N., R. O. Dendy et K. F. Kam. « Electromagnetic ion cyclotron instability driven by a hot minority ion species with temperature anisotropy ». Plasma Physics and Controlled Fusion 35, n^o 11 (1 novembre 1993) : 1529–40. http://dx.doi.org/10.1088/0741-3335/35/11/003.

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Lashmore-Davies, C. N., R. O. Dendy et K. F. Kam. « Electromagnetic ion cyclotron instability driven by a hot minority ion species with temperature anisotropy ». Plasma Physics and Controlled Fusion 36, n^o 3 (1 mars 1994) : 581. http://dx.doi.org/10.1088/0741-3335/36/3/015.

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Kumar, Amit, Ruby Gupta et Jyotsna Sharma. « Electromagnetic Weibel instability in spatial anisotropic electron–ion plasmas ». AIP Advances 12, n^o 6 (1 juin 2022) : 065013. http://dx.doi.org/10.1063/5.0092835.

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The Weibel instability due to temperature anisotropy of electrons and ions in a plasma in the presence of cold and warm ions is reported. Numerical calculations of the normalized growth rate are carried out when the frequency of electromagnetic waves is greater than or less than the thermal velocity of electrons for typical existing plasma parameters. The normalized growth rate increases with an increasing normalized wave number, and after attaining maxima, it decreases due to thermal effects. Therefore, a parabolic plot is obtained for the growth rate. The threshold values of the growth rate depend on the anisotropy parameters. On increasing the value of the temperature anisotropy ratio of either plasma component, the observed growth rate increases. There is a considerable and contrasting effect of the presence of cold and warm ions on the growth rate of the Weibel instability in the plasma. The addition of cold ions stabilizes the instability and reduces the maximum growth rate values, while the addition of warm ions to the plasma increases the instability with a considerable decrease in the domain of instability. Our theoretical investigations of the effect of temperature anisotropy on the growth rate of the Weibel instability are in good agreement with the existing experimental results.

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Livres sur le sujet "Electromagnetic ion temperature"

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Weiland, J. Electromagnetic and kinetic effects on the ion temperature gradient mode. Saskatoon, Sask : Plasma Physics Laboratory, University of Saskatchewan, 1990.

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Asai, H. Theoretical Study of THz Emission from HTS Cuprate. Sous la direction de A. V. Narlikar. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780198738169.013.9.

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This article examines the THz emission from high-temperature superconducting (HTS) cuprates in the mesoscopic state using the intrinsic Josephson junction model. Cuprate superconductors are high-temperature superconductors that exhibit exotic electromagnetic properties. One of the remarkable features of HTS cuprates is high anisotropy due to their layered structures. Almost all HTS cuprates are composed of stacks of CuO2 layers and blocking layers which supply charge carriers to the CuO2 layers. The crystal structures of the HTS cuprates naturally form Josephson junctions known as intrinsic Josephson junctions (IJJs). This article first describes the basic theory of IJJ and the mechanism of THz emission before discussing the effect of temperature inhomogeneity on the emission properties. It then introduces a novel IJJ-based THz emitter that utilizes laser heating. Theoretical results show that the THz emission is caused by the strong excitation of transverse Josephson plasma waves in IJJs under a direct current bias.

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Wolf, E. L. Solar Radiation through the Atmosphere. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198769804.003.0003.

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Maxwell’s equations describe radiated power from the Sun through space and the atmosphere to the Earth. Black-body radiation arises from matter in thermal equilibrium, as is derived in this chapter. The Stefan–Boltzmann power law is derived, and its consequences are discussed. Basics of the atmosphere are discussed, including kinetic energy arising from the condensation of water vapor to liquid water. The temperatures in the atmosphere are discussed in a layered model. The Sun’s light arrives at Earth through vacuum and the Earth’s atmosphere as electromagnetic waves described by Maxwell’s equations. In contemporary electrical engineering jargon, this is “wireless”, that connects cellphones.

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Wright, A. G. Photocathodes. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780199565092.003.0002.

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Optical properties of photocathodes and their characterization in terms of absorptance, transparency, and reflectance in mixed dielectric media are presented. Photometric units and international standards are based on a specified white light source. The electromagnetic spectrum covers about a decade in wavelength and there is a relationship between photon energy and wavelength. Spectral responsivity can be specified in milliamps per watt or as quantum efficiency, η‎(λ‎), in terms of photoelectrons per incident photon. Empirical specifications, based on filtered light from a standard white light source give a measure of the photocathode response to blue, red, and infrared light. Bialkali photocathodes laid on a conducting substrate can operate at ultra-low temperatures approaching absolute zero, while others can survive operation at 200 °C. End window and side window photomultipliers are available in a range of diameters and photocathode types.

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Chapitres de livres sur le sujet "Electromagnetic ion temperature"

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Khoo, T. L. « Evolution of Nuclear Structure with Spin and Temperature ». Dans Weak and Electromagnetic Interactions in Nuclei, 98–105. Berlin, Heidelberg : Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71689-8_25.

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Bernardi, Paolo, Stefano Pisa, Marta Cavagnaro, Emanuel Piuzzi et James C. Lin. « Dosimetry and Temperature Aspects of Mobile-Phone Exposures ». Dans Advances in Electromagnetic Fields in Living Systems, 221–76. New York, NY : Springer New York, 2009. http://dx.doi.org/10.1007/978-0-387-92736-7_7.

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Stochniol, A., et V. S. Nemkov. « Numerical Analysis of Electromagnetic and Temperature Fields in Induction Heated Ferromagnetic Slabs ». Dans Electromagnetic Fields in Electrical Engineering, 243–48. Boston, MA : Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-0721-1_44.

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Ge, Yifan, Shihong Qin et Lixue Chen. « Coupling Analysis of Transient Electromagnetic Field and Temperature Field in Electromagnetic Launch Rail ». Dans Lecture Notes in Electrical Engineering, 1–11. Singapore : Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1870-4_1.

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Bauer, R. W., G. J. Mathews, J. A. Becker, R. E. Howe et R. A. Ward. « Neutron Capture Cross Sections for 86Sr and 87Sr at Stellar Temperatures ». Dans Weak and Electromagnetic Interactions in Nuclei, 984–85. Berlin, Heidelberg : Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-71689-8_188.

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Shevtsov, A. N., et A. A. Zhamaletdinov. « On the Study of Lithosphere Temperature from Electromagnetic Sounding Results ». Dans Springer Proceedings in Earth and Environmental Sciences, 43–53. Cham : Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-35906-5_7.

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Ogi, H., G. Shimoike, M. Hirao, K. Takashima, H. Ohtani et H. Ledbetter. « Electromagnetic Acoustic Resonance of SiCf/Ti Composites at Elevated Temperatures ». Dans Review of Progress in Quantitative Nondestructive Evaluation, 1337–42. Boston, MA : Springer US, 1999. http://dx.doi.org/10.1007/978-1-4615-4791-4_171.

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Ju, Dong Ying, et Pei Bian. « Low-Temperature Sintering and Electromagnetic Properties Evaluation of (Ni/Mn)CuZn Ferrite ». Dans Progress in Powder Metallurgy, 557–60. Stafa : Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-419-7.557.

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Palka, Ryszard, Hardo May et Wolf-Rüdiger Canders. « Nondestructive Quality Testing of High Temperature Superconducting Bulk Material Used in Electrical Machines and Magnetic Bearings ». Dans Optimization and Inverse Problems in Electromagnetism, 303–12. Dordrecht : Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-2494-4_31.

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Buikis, Andris, et Harijs Kalis. « Creation of Temperature Field in a Finite Cylinder by Alternated Electromagnetic Force ». Dans Progress in Industrial Mathematics at ECMI 2002, 247–51. Berlin, Heidelberg : Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-662-09510-2_31.

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Actes de conférences sur le sujet "Electromagnetic ion temperature"

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Araneda, Jaime A. « Electromagnetic Ion/Beam Instabilities In The Fast Solar Wind : Proton Core Temperature Anisotropy Effects On The Relative Drift Speed And Ion Heating ». Dans SOLAR WIND TEN : Proceedings of the Tenth International Solar Wind Conference. AIP, 2003. http://dx.doi.org/10.1063/1.1618649.

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Walther, H. « Spectroscopy of Single Trapped Ions and Application to Frequency Standards ». Dans The European Conference on Lasers and Electro-Optics. Washington, D.C. : Optica Publishing Group, 1998. http://dx.doi.org/10.1364/cleo_europe.1998.ctud1.

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Single ions trapped and laser cooled provide ideal objects for high resolution spectroscopy and frequency standards. For the latter purpose we are investigating the 5s2 1S0 → 5s5p 3P0 transition of In+. With a natural linewidth of only 1.1 Hz this resonance offers very high resolution and is highly immune to frequency shifts due to external electromagnetic fields, because it connects two levels with vanishing electronic magnetic momenta [1]. The wavelength of this clock transition is 236.5 nm and is technically very convenient, since it coincides with the fourth harmonic of the 946 nm Nd:YAG laser line. So this intrinsically frequency stable solid-state laser can be used to excite the transition [2]. For laser cooling and fluorescence detection of the indium ion the 5s2 1So -> 5s5p 3P1 transition at 230.6 nm can be employed. The use of the relatively narrow intercombination line for laser cooling allows us to study optical sideband cooling in the strong binding regime, where the oscillation frequencies of the ion in the trap (around 1 MHz) are larger than the optical linewidth of 360 kHz. In this parameter range laser cooling is possible to the quantum ground state of the vibrational motion in the trap corresponding to a temperature of roughly 100 μK. The same low temperature was obtained with sideband cooling of a small Coulomb crystal consisting of two ions, creating an interesting new quantum few-particle system.

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Alabastri, Alessandro, Andrea Toma, Mario Malerba et Remo Proietti Zaccaria. « Temperature modulated nanoplasmonics ». Dans 2016 Progress in Electromagnetic Research Symposium (PIERS). IEEE, 2016. http://dx.doi.org/10.1109/piers.2016.7734765.

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Lontano, Maurizio. « Relativistic electromagnetic solitons in a high temperature plasma ». Dans SUPERSTRONG FIELDS IN PLASMAS : Second International Conference on Superstrong Fields in Plasmas. AIP, 2002. http://dx.doi.org/10.1063/1.1470332.

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Muzalevskiy, K. V., Z. Ruzicka, L. G. Kosolapova et V. L. Mironov. « Temperature dependence of SMOS/MIRAS, GCOM-W1/AMSR2 brightness temperature and ALOS/PALSAR radar backscattering at arctic test sites ». Dans 2016 Progress in Electromagnetic Research Symposium (PIERS). IEEE, 2016. http://dx.doi.org/10.1109/piers.2016.7735375.

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Pekala, Robert, Bogdan Kwiatkowski et Tadeusz Kwater. « Electromagnetic and Temperature Fields Calculations in the Ferromagnetic Medium ». Dans 2018 Progress in Applied Electrical Engineering (PAEE). IEEE, 2018. http://dx.doi.org/10.1109/paee.2018.8441110.

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Fan, Xinyan, Guochun Wan et Meisong Tong. « Temperature and strain properties of photonic bandgap fiber sensors ». Dans 2016 Progress in Electromagnetic Research Symposium (PIERS). IEEE, 2016. http://dx.doi.org/10.1109/piers.2016.7734682.

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Hernandez-Valle, F., S. Dixon, Donald O. Thompson et Dale E. Chimenti. « PULSED ELECTROMAGNET EMAT FOR HIGH TEMPERATURES ». Dans REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION VOLUME 29. AIP, 2010. http://dx.doi.org/10.1063/1.3362535.

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Artamonov, E. V. « Investigation of Electromagnetic Properties of Tool Hard Alloys under the Influence of High Temperatures ». Dans Modern Trends in Manufacturing Technologies and Equipment. Materials Research Forum LLC, 2022. http://dx.doi.org/10.21741/9781644901755-57.

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Abstract. The article shows the developed installation for determination of temperature of maximum operability of replaceable cutting hard-alloy plates on the basis of study of change of electromagnetic properties. The method of research is given. Tests of images were carried out to time of heating of the replaceable cutting plates from solid B35 alloy. The heating temperature interval was selected according to the temperature mode of the process of cutting difficult materials. Heating was carried out to 1000˚ C. The results of the study were obtained to determine the temperature of maximum operability of replaceable cutting hard alloy plates based on the study of the change in electromagnetic properties for alloy В35 amounted to 460-730 ° С.

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Lu, Tien-Chang. « Robust and ultracompact room temperature operated surface plasmon polariton nanolasers ». Dans 2016 Progress in Electromagnetic Research Symposium (PIERS). IEEE, 2016. http://dx.doi.org/10.1109/piers.2016.7734213.

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Rapports d'organisations sur le sujet "Electromagnetic ion temperature"

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Galperin, Yu M., D. A. Parshin et V. N. Solovyev. Nonlinear Low-Temperature Absorption of Ultrasound and Electromagnetic Waves in Glasses. [б. в.], août 1989. http://dx.doi.org/10.31812/0564/1243.

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Our aim is to consider nonlinear absorption of ultrasonic (or electromagnetic) waves by two-level systems (TLS's ) in glasses. We are interested in the relaxational contribution to the absorption (the resonant one, if present, saturates at very low intensity of the wave).

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Samn, Sherwood W. Mathematical Modeling of the Temperature Rise in a Thin Cell Culture Exposed to High Frequency Electromagnetic Irradiation. Fort Belvoir, VA : Defense Technical Information Center, juin 2003. http://dx.doi.org/10.21236/ada416616.

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Friedman, Shmuel, Jon Wraith et Dani Or. Geometrical Considerations and Interfacial Processes Affecting Electromagnetic Measurement of Soil Water Content by TDR and Remote Sensing Methods. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7580679.bard.

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Time Domain Reflectometry (TDR) and other in-situ and remote sensing dielectric methods for determining the soil water content had become standard in both research and practice in the last two decades. Limitations of existing dielectric methods in some soils, and introduction of new agricultural measurement devices or approaches based on soil dielectric properties mandate improved understanding of the relationship between the measured effective permittivity (dielectric constant) and the soil water content. Mounting evidence indicates that consideration must be given not only to the volume fractions of soil constituents, as most mixing models assume, but also to soil attributes and ambient temperature in order to reduce errors in interpreting measured effective permittivities. The major objective of the present research project was to investigate the effects of the soil geometrical attributes and interfacial processes (bound water) on the effective permittivity of the soil, and to develop a theoretical frame for improved, soil-specific effective permittivity- water content calibration curves, which are based on easily attainable soil properties. After initializing the experimental investigation of the effective permittivity - water content relationship, we realized that the first step for water content determination by the Time Domain Reflectometry (TDR) method, namely, the TDR measurement of the soil effective permittivity still requires standardization and improvement, and we also made more efforts than originally planned towards this objective. The findings of the BARD project, related to these two consequential steps involved in TDR measurement of the soil water content, are expected to improve the accuracy of soil water content determination by existing in-situ and remote sensing dielectric methods and to help evaluate new water content sensors based on soil electrical properties. A more precise water content determination is expected to result in reduced irrigation levels, a matter which is beneficial first to American and Israeli farmers, and also to hydrologists and environmentalists dealing with production and assessment of contamination hazards of this progressively more precious natural resource. The improved understanding of the way the soil geometrical attributes affect its effective permittivity is expected to contribute to our understanding and predicting capability of other, related soil transport properties such as electrical and thermal conductivity, and diffusion coefficients of solutes and gas molecules. In addition, to the originally planned research activities we also investigated other related problems and made many contributions of short and longer terms benefits. These efforts include: Developing a method and a special TDR probe for using TDR systems to determine also the soil's matric potential; Developing a methodology for utilizing the thermodielectric effect, namely, the variation of the soil's effective permittivity with temperature, to evaluate its specific surface area; Developing a simple method for characterizing particle shape by measuring the repose angle of a granular material avalanching in water; Measurements and characterization of the pore scale, saturation degree - dependent anisotropy factor for electrical and hydraulic conductivities; Studying the dielectric properties of cereal grains towards improved determination of their water content. A reliable evaluation of the soil textural attributes (e.g. the specific surface area mentioned above) and its water content is essential for intensive irrigation and fertilization processes and within extensive precision agriculture management. The findings of the present research project are expected to improve the determination of cereal grain water content by on-line dielectric methods. A precise evaluation of grain water content is essential for pricing and evaluation of drying-before-storage requirements, issues involving energy savings and commercial aspects of major economic importance to the American agriculture. The results and methodologies developed within the above mentioned side studies are expected to be beneficial to also other industrial and environmental practices requiring the water content determination and characterization of granular materials.

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