scholarly journals Theoretical Studies of Low Frequency Instabilities in the Ionosphere. Final Report

2003 ◽  
Author(s):  
Y. S. Dimant
Keyword(s):  
Low Frequency ◽  
Final Report ◽  
Theoretical Studies

scholarly journals MHD-waves in the geomagnetic tail: A review

10.12737/7168 ◽  
2015 ◽  
Vol 1 (1) ◽  
pp. 4-22 ◽  
Author(s):  
Анатолий Леонович ◽  
Anatoliy Leonovich ◽  
Виталий Мазур ◽  
Vitaliy Mazur ◽  
Даниил Козлов ◽  
...  
Keyword(s):  
Numerical Models ◽  
Experimental Studies ◽  
Low Frequency ◽  
Detailed Comparison ◽  
Mhd Waves ◽  
Theoretical Studies ◽  
Geomagnetic Tail ◽  
Magnetopause Oscillations ◽  
Experimental And Theoretical Studies ◽  
Theoretical Results

This article presents the review of experimental and theoretical studies on ultra-low-frequency MHD oscillations of the geomagnetic tail. We consider the Kelvin–Helmholtz instability at the magnetopause, oscillations with a discrete spectrum in the “magic frequencies” range, the ballooning instability of coupled Alfvén and slow magnetosonic waves, and “flapping” oscillations of the current sheet of the geomagnetic tail. Over the last decade, observations from THEMIS, CLUSTER and Double Star satellites have been of great importance for experimental studies. The use of several spacecraft allows us to study the structure of MHD oscillations with high spatial resolution. Due to this, we can make a detailed comparison between theoretical results and those obtained from multi-spacecraft studies. To make such comparisons in theoretical studies, in turn, we have to use the numerical models closest to the real magnetosphere.

scholarly journals Low frequency RF current drive. Final report, January 1, 1988--May 31, 1997

1999 ◽  
Author(s):  
N. Hershkowitz
Keyword(s):  
Low Frequency ◽  
Current Drive ◽  
Final Report

scholarly journals Coupled models in low-frequency electromagnetic simulation LDRD Final Report 94-ERI-004

1997 ◽  
Author(s):  
D.W. Hewett ◽  
D. Bateson ◽  
M. Gibbons ◽  
M. Lambert ◽  
L. Tung ◽  
...  
Keyword(s):  
Low Frequency ◽  
Electromagnetic Simulation ◽  
Final Report ◽  
Coupled Models

scholarly journals Study of spider pulsar binary eclipses and discovery of an eclipse mechanism transition

2020 ◽  
Vol 494 (2) ◽  
pp. 2948-2968 ◽  
Author(s):  
E J Polzin ◽  
R P Breton ◽  
B Bhattacharyya ◽  
D Scholte ◽  
C Sobey ◽  
...  
Keyword(s):  
Direct Evidence ◽  
Low Frequency ◽  
Line Of Sight ◽  
Observational Constraints ◽  
Main Body ◽  
Theoretical Studies ◽  
Wide Range ◽  
Order Of Magnitude ◽  
Mechanism Transition ◽  
Hubble Time

ABSTRACT We present a comparative study of the low-frequency eclipses of spider (compact and irradiating binary) PSRs B1957+20 and J1816+4510. Combining these data with those of three other eclipsing systems we study the frequency dependence of the eclipse duration. PSRs B1957+20 and J1816+4510 have similar orbital properties, but the companions to the pulsars have masses that differ by an order of magnitude. A dedicated campaign to simultaneously observe the pulsed and imaged continuum flux densities throughout the eclipses reveals many similarities between the excess material within the two binaries, irrespective of the companion star properties. The observations show that the pulsar fluxes are removed from the line of sight throughout the main body of the eclipses. For PSR J1816 + 4510, we present the first direct evidence of an eclipse mechanism that transitions from one that removes the pulsar flux from the line of sight to one that merely smears out pulsations, and claim that this is a consequence of scattering in a tail of material flowing behind the companion. Inferred mass-loss rates from the companion stars are found to be $\dot{M}_{\text{C}} \sim 10^{-12}$ and $\sim 2 \times 10^{-13}\,\mathrm{M}_\odot$ yr−1 for PSR B1957+20 and PSR J1816 + 4510, respectively; seemingly too low to evaporate the stars within Hubble time. Measurements of eclipse durations over a wide range of radio frequencies show a significant dependence of eclipse duration on frequency for all pulsars, with wider eclipses at lower frequencies. These results provide a marked improvement in the observational constraints available for theoretical studies of the eclipse mechanisms.

scholarly journals Dielectric Constants of a Binary Solution Near the Critical Solution Temperature

1973 ◽  
Vol 51 (4) ◽  
pp. 545-550 ◽  
Author(s):  
I. Lubezky ◽  
R. McIntosh
Keyword(s):  
High Frequency ◽  
Binary Solution ◽  
Critical Concentration ◽  
Low Frequency ◽  
Dielectric Constants ◽  
Solution Temperature ◽  
Dielectric Losses ◽  
Theoretical Studies ◽  
Critical Solution Temperature ◽  
Experimental Knowledge

The dielectric constants and dielectric losses of solutions of nitrobenzene and 2,2,4-trimethyl pentane have been measured near the critical solution temperature over a concentration range of 22–75% by weight and in the frequency regions of 5–60 and 1000 – 4000 kHz. It was found that below a critical concentration of 35% maxima existed in ε′ and ε″ at a temperature of 0.3 °C above the critical solution temperature. At higher concentrations the maxima disappeared and phase separation was preceded only by changes in the thermal coefficients dε′/dT and dε″/dT. The present study combined with others indicates that two regions of loss exist for the system near the critical temperature: low frequency losses of a conductive nature and high frequency losses of the Debye type. The published experimental knowledge of such systems remains insufficient to enable a thorough test of the theoretical studies published recently by Snider.

scholarly journals Theoretical studies of edge physics and plasma-wall interactions: Final report

1989 ◽  
Author(s):  
D. Harned ◽  
C. Birdsall
Keyword(s):  
Final Report ◽  
Theoretical Studies ◽  
Wall Interactions
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