Theory, lab and space experiments, and calculations related the physics of [plasmas](https://en.wikipedia.org/wiki/Plasma_(physics)), i.e., matter constituted by [ionized atoms](https://en.wikipedia.org/wiki/Ion).

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Possible Safe Areas In a Solar Flare

Which part of the earth would be the safest in case of the major solar flare? Will it be near equator or something like that?
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What causes a charged particle to follow circular motion in a magnetic field? [duplicate]

I would like to know why particles follow a circular path in a magnetic field, what path they trace and how this path is measured and controlled?
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Does the solar wind correspond to a net electrical current?

The solar wind is a stream of ions emitted from the sun. Are there more positive than negative charges released? That is, is there any imbalance in the charge emitted from the sun in the solar wind?
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Why does an oscillating electric field couple more strongly to electrons than to ions?

As stated in Principles of Plasma Discharges and Materials Processing, by M. A. Lieberman and A. J. Lichtenberg, about capacitively coupled plasmas: (...) the light and heavy charged particles in ...
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The velocity of the charged particle in the magnetic field [duplicate]

Enrico Fermi considered that moving charged particle gains energy in the magnetic field, so its velocity increases. According to the Lorentz Law $\vec F=q\vec v\times\vec B$. Work is $A=\vec ...
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Why doesn't the group velocity of a plasma EM wave equal the phase velocity here?

For plasma EM waves we have the dispersion relation $$\omega^2=\omega_p^2+c^2k^2$$ where the plasma frequency $$\omega_p^2=\frac{n_e e^2}{\epsilon_0 m_e}$$ One can show that $v_p v_g=c^2$, i.e., the ...
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What is the role of plasma in nuclear fusion energy production?

I read that confined plasma in electromagnetic field uses in TOKAMARK nuclear fusion reaction.But I don't know what is the main role of plasma in fusion reaction. Is it use for producing energy ...
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Can conducting electrons in a metal be modeled at all as classical particles?

I have seen computational models that treat the highest energy electrons in a conducting metal as classical particles in a plasma, the ions being held in place with some sort of heuristic ...
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What is the difference between metallic hydrogen and plasma of hydrogen?

As far as I know, metallic hydrogen and plasma seems share some common properties, eg:conduct electricity, nuclei share electrons, high temperatures... So my question is, is metallic hydrogen in fact ...
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Is there any electric current in a continuous medium of moving charges?

Suppose that unlike in real life where charge is carried in fixed discrete chunks like electrons that one has a continuous fluid in a bottle that carries charges. Suppose that the fluid is stirred in ...
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Project Orion pusher plate computer modeling

Linked from the space.stackexchange forum: http://space.stackexchange.com/questions/15051/orion-project-npp-pusher-plate-computer-models-and-survivability Project Orion is discussed as if it is a ...
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Do stars remain electrically neutral? [duplicate]

How electrically neutral do stars remain through their lifetime? As an example, I could imagine processes such as coronal mass ejections leaving the Sun in a slightly charged state. Are there such ...
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A question about the Fermi acceleration

In high school physics, we know that a charged particle cannot gain energy from a magnetic field. But, it seems that in the so-called Fermi acceleration, the particle is accelerated by the magnetic ...
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GEN3's 10nm-30nm Contiuum Radiation Measurements

What is the most likely explanation for the 10nm-30nm continuum radiation reported in "Validation of the Observation of Soft X-ray Continuum Radiation from Low-Energy Pinch Discharges in the Presence ...
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39 views

Does nuclear fusion of light nuclei occur in fire or boiling water?

At the temperature range of ordinary fire or maybe even ordinary boiling water, is the Coulomb potential between light atomic nuclei occasionally overcome to give way to fusion? Basically, how are ...
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Plasma Seperation Technique

Is it possible to break a gas sample in ions and separate those ions and store in two different tubes? If there is an experiment and formula related to it then please mention that too.
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Is the permeability of plasma equal to the permeability of free space?

I learned that in Maxwell equations for plasma, the permeability is equal to the permeability of free space so that means the relative permeability is equal to the unit tensor. Also we have always ...
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What causes polarization current density in plasma?

Plasma current density is defined as $\textbf{j}=-\mathrm{e}n_e\textbf{u}_e$ where $\mathrm{e}$ is electron charge, $n_e$ is electron concentration and $\textbf{u}_e$ is electron velocity. What ...
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Schwinger metals?

Consider an electromagnetic field that does reach values above the Schwinger limit inside a region of space $R$, on each oscillation. Once the field exceeds the Schwinger intensity, the field causes ...
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Ion Source Design

I want to design a DC arc discharge ion source but I can't find a good book that explains how to do it. Can anyone please recommend me a book or paper that explains this? thanks
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Polarization current introduced by induced charge?

Should we count the current density that introduced by the movement of induced charge as free current or magnetized current or neither? And why?
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Physics 3 recommended book with solutions [duplicate]

I'm new to this forum and wanted to ask for a recommendation for a book which has these subjects with problems and solutions:(if this is not a valid question please tell me) -Intro to Waves -Fourier ...
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Is green superheated plasma possible?

I've noticed that video games like Fallout 4 depict the plasma fired from plasma weapons as green. Is there a way hot plasma can look green in real life? I know some gases emit green light when ...
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Recombination rate/time calculation for plasma vs. solid state semiconductors

I've been able to find how to calculate the recombination rate for semiconductors as a function of the type of semiconductor (like silicon), the doping material, the concentration of the excess ...
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What phenomena occur in a low voltage arc between copper and graphite electrodes, and why is the result dependent on electrode polarity?

I was playing around with a laboratory power supply, drawing arcs between electrodes of various materials. I noticed phenomena that I found interesting, and couldn't really explain myself: The ...
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What makes Jacob's ladder spark to go upwards?

In a Jacob's ladder (https://www.youtube.com/watch?v=GaC4BnbH1NY&index=3&list=PL_SAbPKia2YMFi-t8z5WFYCd86Plcs1Un) a spark is originated in the bottom and climbs up to the top. I have read in ...
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Do plasmas have their own magnetic fields?

Do Plasma generate a magnetic field of their own ? Can they cause electromagnetic induction?? For example if a hydrogen plasma is ionized and its electrons removed.. And the protons accelerated ...
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1kg mass impacting at half light speed - effects?

Such a mass would have kinetic energy approximating a 1 mega-tonne thermonuclear weapon. So, what would such an object do if it hit the Earth? We know how destructive such an energy release can be, ...
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What state of matter is thunder? [closed]

I know of solid, liquid and gaseous states of matter but what state of matter is thunder? Is it gas, liquid or solid?
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Why is a stellarator-type nuclear fusion reactor so oddly-shaped?

My first impression: It's a mess. Why is it shaped like that? I can't find any info about its shape other than it's a special arrangement of magnetic coils. (link) Here's some more images of it on ...
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Why did they start Wendelstein 7-X With Helium?

Just saw the first Hydrogen plasma at the Wendelstein reactor. I haven't found anywhere that gives a good explanation as to why they first used a Helium plasma - can anyone shed any light?
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Potential energy of a spherically symmetric charge density in a spherically symmetric electrostatic potential

I'm interested in calculating the potential energy of a spherically symmetric charge density in a spherically symmetric electrostatic potential. More specific, I'm currently trying to calculate the ...
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1answer
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Differences between thermal and non-thermal plasmas

I have a doubt about plasmas which may as well be trivial or very stupid, but I couldn't get a clear and straightforward answer anywhere I looked, and I can't get the grasp of it since I wasn't given ...
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Estimating temperature with Boltzmann relation with split emission lines

I'm trying to estimate the temperature of a plasma through the use of hydrogen lines, $H_{\alpha}$ and $H_{\beta}$ using the Boltzmann relation: $$ \frac{ n_{2} }{ n_{1} } = \frac{ g_{2} }{ g_{1} ...
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Difference between reflection mechanisms in dielectric, metals and plasma

How the reflection and transmissions mechanism are different in metals, dielectric and plasma? I know that the density of free electrons is playing the role. Can anyone give an insight what is ...
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Plasma Ball and effect of Humans

If one brings a fluorescent bulb close to a plasma ball, why does the touch of a finger cause the bulb to become brighter when touched? Why, when you hold the metal portion of the bulb, as opposed ...
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Response function in plasma

I am reading an article where authors investigate how a particular type of electrostatic waves propagates in a plasma. They start with the Poisson's equation in the next form: $$\nabla^2 ...
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Would a mass of bare iron nuclei be visible ?

As I understand it most of how objects look is because of how photons interact with electrons and photons emitted when excited electrons fall to lower energy levels producing photons. So if one traps ...
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Liquid/solid to plasma?

During a phase change we can go from solid to gas via the process of sublimation. The diagram given below indicates that there is no analogous process for the transition from solid (or liquid) to ...
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Why is the enclosed area of a voltage-charge Lissajous figure to the dissipated energy per cycle?

These Lissajous figures turn up in the study of Dielectric Barrier Discharges driven by AC voltages, but I believe the concept of the "dissipated energy=area enclosed curve" is much more general. By ...
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What is crater's influence on laser ablation?

In many laser ablation experiments (especially Pulsed Laser Deposition), target is moving to avoid crater formation. But I can't find any source that says why it is needed to avoid it. So why is ...
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What is meant by infinite wavelength?

1#When an electromagnetic wave propagates in a plasma, with increase in plasma density the phase velocity ($v=\frac{\omega}{k}$) of wave increases. So at cut-off point $k=0$, and phase velocity ...
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The basic physics behind the plasma frequency

The dispersion relation of ordinary wave in plasma is \begin{equation} \omega^2=\omega_{p}^{2}+c^{2}k^{2}, \end{equation} where $\omega_{p}=\sqrt{{4\pi n_{0}e^{2}}/{m}}$ is the plasma frequency. ...
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plasma frequency in terms of thermal energy

The relativistic factor (in terms of momentum) is given by \begin{equation}\label{} \gamma=1/\sqrt{1-v^{2}/c^{2}}=\sqrt{1+p^{2}/m^{2}_{0}c^{2}}, \end{equation} When thermal momentum is greater ...
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Can a spheromak propagate in vacuum?

I recently learned about (and am now fascinated by) spheromaks. I am no expert on plasma physics, but as I understand they are analogous to propagating toroidal vortices (smoke rings), but with plasma ...
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What defines a cold plasma?

Been looking for this very simple answer for a while now, and google returns a face cream with the words cold plasma in it. Very frustrated. Just wondering, what constitutes a cold plasma in the ...
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How much do we know about the characteristic time for electron-ion recombination for a dense plasma?

As mentioned, how much do we know about the characteristic time for electron-ion recombination for a dense (noble gas) plasma (i.e. density of electrons at $\approx 10^{21} \textrm{cm}^{-3}$) at ...
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What are the equations needed to determine pressure and velocity/acceleration of a plasma in a electromagnet coil

I am trying to develop a new type of fuel injector, however I am having trouble finding the plasma dynamics equations I need. I also am having trouble finding the equations to determine the ...
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The change of length of positive column in glow discharge

When I was doing the experiment of glow discharge, I lowered the voltage between electrodes and find that the length of positive column will increased quickly around a certain voltage(the interval of ...
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Pair correlation function of the QHE “plasma”

I am trying to teach myself the theory of quantum Hall effect, and realized that I can not reproduce a basic textbook result. Let me closely follow Girvin's Les Houches lectures ...