Results 21 to 30 of about 30,961 (212)

Interpretation of core ion cyclotron emission driven by sub-Alfvénic beam-injected ions via magnetoacoustic cyclotron instability [PDF]

Nuclear Fusion, 2019
Core ion cyclotron emission (ICE) signals have recently been observed in beam-heated plasmas on several tokamaks. In this manuscript we present experimental evidence in support of core ICE being generated by the magnetoacoustic cyclotron instability (MCI), itself driven by the velocity-space inversion of sub-Alfvenic beam-injected ions.
R. Ochoukov, K.G. McClements, R. Bilato, V. Bobkov, B. Chapman, S.C. Chapman, R.O. Dendy, M. Dreval, H. Faugel, J.-M. Noterdaeme, M. Salewski, M. Weiland   +11 more
openaire   +3 more sources

Discovery of proton hill in the phase space during interactions between ions and electromagnetic ion cyclotron waves

Scientific Reports, 2021
A study using Arase data gives the first observational evidence that the frequency drift of electromagnetic ion cyclotron (EMIC) waves is caused by cyclotron trapping.
Masafumi Shoji, Yoshizumi Miyoshi, Lynn M. Kistler, Kazushi Asamura, Ayako Matsuoka, Yasumasa Kasaba, Shoya Matsuda, Yoshiya Kasahara, Iku Shinohara   +8 more
doaj   +1 more source

Parametric Decay Instabilities during Electron Cyclotron Resonance Heating of Fusion Plasmas, Problems and Possibilities [PDF]

EPJ Web of Conferences, 2023
We review parametric decay instabilities (PDIs) expected in connection with electron cyclotron resonance heating (ECRH) of magnetically confined fusion plasmas, with a specific focus on conditions relevant for the ITER tokamak.
Hansen S.K., Nielsen S.K., Stober J., Rasmussen J., Salewski M., Willensdorfer M., Hoelzl M., Stejner M.   +7 more
doaj   +1 more source

Toroidal flow measurements of impurity ions in QUEST ECH plasmas using multiple viewing chords emission spectroscopy

Nuclear Materials and Energy, 2021
A spectroscopic system with multiple viewing chords was developed for QUEST (Q-shu University Experiment with Steady-State Spherical Tokamak) to measure the spatial distribution of ion toroidal velocities in discharges sustained by electron cyclotron ...
N. Yoneda, T. Shikama, K. Hanada, S. Mori, T. Onchi, K. Kuroda, M. Hasuo, A. Ejiri, K. Matsuzaki, Y. Osawa, Y. Peng, Y. Kawamata, S. Sakamoto, H. Idei, T. Ido, K. Nakamura, Y. Nagashima, R. Ikezoe, M. Hasegawa, A. Higashijima, T. Nagata, S. Shimabukuro   +21 more
doaj   +1 more source

Electrodynamics of Magnetars: Implications for the Persistent X-ray Emission and Spindown of the Soft Gamma Repeaters and Anomalous X-ray Pulsars [PDF]

, 2001
(ABBREVIATED) We consider the structure of neutron star magnetospheres threaded by large-scale electrical currents, and the effect of resonant Compton scattering by the charge carriers (both electrons and ions) on the emergent X-ray spectra and pulse ...
Basko M. M., Blandford R. D., C. Thompson, Fuchs Y., Golenetskii S. V., Haberl F., Lynden-Bell D., M. Lyutikov, Mazets E. P., Mestel L., Mitrofanov I. G., Neuhauser R., Oosterbroek T., Paczynski B., S. R. Kulkarni, Thompson C., Zeldovich Ya. B., Zheleznyakov V. V., Zheleznyakov V. V.   +18 more
core   +2 more sources

Two Dimensional Full‐Wave Modeling of Propagation of Low‐Altitude Hiss in the Ionosphere

Geophysical Research Letters, 2020
We investigate the propagation characteristics of low‐altitude hiss in the ionosphere by numerical simulation with a two‐dimensional full‐wave model. The simulation results demonstrate that linear mode conversion from whistler to H+ band electromagnetic ...
Xiang Xu, Chen Zhou, Lunjin Chen, Zhiyang Xia, Xu Liu, Jamesina J. Simpson, Yuannong Zhang   +6 more
doaj   +1 more source

On the Nature of Pulsar Radio Emission [PDF]

, 1998
A theory of pulsar radio emission generation, in which the observed waves are produced directly by maser-type plasma instabilities operating at the anomalous cyclotron-Cherenkov resonance $\omega- k_{\parallel} v_{\parallel} + \omega_B/ \gamma_{res}=0 ...
Arons, Arons, Arons, Arons, Blandford, Chugunov, Daugherty, Didenko, Galuzo, George Machabeli, Ginzburg, Gwinn, Hankins, Harrison, Kazbegi, Kazbegi, Kazbegi, Kazbegi, Kramer, Kramer, Lesch, Lominadze, Lominadze, Lorimer, Luo, Lyne, Lyutikov, Lyutikov, Lyutikov, Lyutikov, Lyutikov, Lyutikov, Machabeli, Manchester, Manchester, Markwardt, Maxim Lyutikov, Melrose, Melrose, Moffett, Nusinovich, Rankin, Roger D. Blandford, Schwinger, Tademaru, Usov, Volokitin, Yadigaroglu, Zheleznyakov   +48 more
core   +4 more sources

Resonance in radio frequency sheath admittance and enhanced impurity emission near the ion cyclotron frequency

Nuclear Fusion, 2023
Ion cyclotron resonance heating (ICRH) is of considerable interest among all auxiliary heating techniques, because it transfers power directly to ions, targets the high-density core, and involves the cheapest radio-frequency (RF) components.
Mikhail Rezazadeh, James R. Myra, Davide Curreli   +2 more
doaj   +1 more source

Atmospheres and Spectra of Strongly Magnetized Neutron Stars [PDF]

, 2001
We construct atmosphere models for strongly magnetized neutron stars with surface fields $B\sim 10^{12}-10^{15}$ G and effective temperatures $T_{\rm eff}\sim 10^6-10^7$ K.
Ho, Wynn C. G., Lai, Dong
core   +2 more sources

Ion Temperatures in the Low Solar Corona: Polar Coronal Holes at Solar Minimum [PDF]

, 2008
In the present work we use a deep-exposure spectrum taken by the SUMER spectrometer in a polar coronal hole in 1996 to measure the ion temperatures of a large number of ions at many different heights above the limb between 0.03 and 0.17 solar radii.
Avrett, Axford, Banerjee, Barakat, Barakat, Cranmer, Cranmer, Cranmer, Cranmer, Cranmer, Cranmer, Cranmer, Cranmer, Cranmer, Dum, E. Landi, Esser, Isenberg, Kellogg, Kohl, Laming, Landi, Landi, Lie-Svendsen, Markovskii, Markovskii, Marsch, Moran, Ruzmaikin, S. R. Cranmer, Spitzer, Verma, Zangrilli, Zhang   +33 more
core   +1 more source