Single-Particle Radiation Processes in a Plasma with Magnetic Fields

Current work presents an optical setup, its calibration and reference process and the first results from single particle emissivity measurements of pulverized biomass and coal fuel particles. In contrast to earlier attempts, the setup offers the possibility of emissivity measurements during the whole particle burn-off. A laser ignites a single particle, placed in the center of the setup. Two photomultipliers observe the emitted particle radiation in the visible range (550 nm and 700 nm) for temperature calculation, using two-color pyrometry. An InSb-detector records the emitted particle radiation between 2.4 µm and 5.5 µm, which is later used to calculate particle emissivity in this range. The conclusion of multiple particle measurements lead to decreasing particle emissivity with increasing temperature. For coal particles the emissivity decreases from 0.45 at 2300 K to 0.03 at 3400 K. Biomass char shows a similar trend with a decrease from 0.18 (2100 K) to 0.03 (2900 K).

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Width dependent collisionless electron dynamics in the static fields of the shock ramp, 1, Single particle behavior and implications for downstream distribution

Nonlinear Processes in Geophysics ◽

10.5194/npg-4-167-1997 ◽

1997 ◽

Vol 4 (3) ◽

pp. 167-172 ◽

Cited By ~ 2

Author(s):

M. Gedalin ◽

M. A. Balikhin

Keyword(s):

Magnetic Fields ◽

Electron Temperature ◽

Single Particle ◽

Electron Distribution ◽

Trajectory Analysis ◽

Electron Motion ◽

Electron Dynamics ◽

Electron Trajectories ◽

Electric And Magnetic Fields ◽

Downstream Distribution

Abstract. We study the collisionless dynamics of electrons in the shock ramp using the numerical trajectory analysis in the model electric and magnetic fields of the shock. Even with very modest assumptions about the cross-shock potential the electron trajectories are very sensitive to the width of the ramp. The character of electron motion changes from the fully adiabatic (with conservation of v2<perp> /B) when the ramp is wide, to the nonadiabatic one, when the ramp becomes sufficiently narrow. The downstream electron distribution also changes drastically, although this change depends on the initial electron temperature.

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Fault Tolerant Memories for Single Particle Radiation Effects

IEEE Transactions on Nuclear Science ◽

10.1109/tns.1981.4335662 ◽

1981 ◽

Vol 28 (6) ◽

pp. 3998-4003 ◽

Cited By ~ 4

Author(s):

John P. Retzler

Keyword(s):

Single Particle ◽

Radiation Effects ◽

Fault Tolerant ◽

Particle Radiation

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Locating Schumann Resonant Frequencies on a Single Particle Radiation Patterns Using Golden Ratio Spiral and Octave Relationship of Schumann Points.

10.5194/egusphere-egu21-9927 ◽

2021 ◽

Author(s):

Mert Yucemoz

Keyword(s):

Radiation Pattern ◽

Single Particle ◽

High Frequency ◽

Numerical Models ◽

Golden Ratio ◽

Lightning Discharge ◽

Low Frequency ◽

Radiation Patterns ◽

Particle Radiation ◽

Schumann Resonances

<p>Although lightning discharge is not the only source or only physical phenomenon that affects the Schumann resonances, they have the highest contribution to the Schumann resonances oscillating between the ground the ionosphere. Schumann resonances are predicted through several different numerical models such as the transmission-line matrix model or partially uniform knee model. This contribution reports a different prediction method for Schumann resonances derived from the first principle of fundamental physics combining both particle radiation patterns and the mathematical concept of the Golden ratio. This prediction allows the physical understanding of where Schumann resonances originate from radiation emitted by a particle that involves many frequencies that are not related to Schumann resonances. In addition, this method allows predicting the wave propagation direction of each frequency value in the Schumann frequency spectrum. Particles accelerated by lightning leader tip electric fields are capable of contributing most of the Schumann resonances. The radiation pattern of a single particle consists of many frequencies. There are only specific ones within this pattern that contribute to the Schumann radiation. The vast majority of Schumann resonances distribute quite nicely obeying the Golden ratio interval. This property, used in conjunction with the full single-particle radiation patterns, also revealed that high-frequency forward-backward peaking radiation patterns, as well as low-frequency radiation patterns, can contribute to Schumann resonances. This method allows to locate them on the full radiation pattern. A theoretical analysis using the Golden ratio spiral, predict that there are more Schumann resonances in the high-frequency forward-backward peaking radiation pattern of a relativistic particle than low-frequency dipole radiation pattern. Extending the idea to an octave that identifies the identical sounding notes with different frequencies in standing waves. By knowing the value of the initial Schumann resonant frequency, this method allows us to predict the magnitude of other Schumann resonances on the radiation pattern of a single accelerated charged particle conveniently. In addition, it also allows us to find and match Schumann resonances that are on the same radiation lobe, which is named electromagnetic Schumann octaves. Furthermore, it is important to find Schumann octaves as they propagate in the same direction and have a higher likelihood of wave interference.</p>

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