Theory, experiments and calculations related the physics of plasmas, i.e., matter constituted by ionized atoms.

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What happens to the electrons that escape an atom when matter is converted to a plasma state?

Lets say we have a device that generates plasma fields; if this device creates plasma by heating a gas, where do the electrons that escaped the "orbits" of the atom go? Would the electron physically ...
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53 views

What will happen if we will be able to produce a quark-gluon plasma and the we cool it down?

Lets assume that we can produce a quark-gluon plasma and then we try to cool it down, what will happen to it ?
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86 views

Does the 1-D poisson's equation have monotonic potentials if $\rho=\rho(\phi(z))$?

I am solving the 1-D poisson equation: $$\frac{d^2 \phi}{dz^2}=-4\pi\rho(\phi)$$ with the additional requirement that $\rho(\phi(z=0))=0$. If I start by multiplying each side by $\frac{d\phi}{d z}$ ...
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93 views

Using a Plasma Globe to generate real random numbers

I have been thinking how to easily generate real random numbers when I cam across the small USB-powered Plasma globe. My idea would be to place it in front of an light sensor and read the sensor's ...
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72 views

Convective derivative of oscillating fluid with bulk motion?

I have a fluid $u$, which comprises a zeroth order constant motion $u_0$ as well as a first order oscillatory motion $u_1$. The convective derivative is $$\frac{\partial u}{\partial t} ...
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414 views

Geiger meter affected by plasma lamp

Whilst testing a geiger meter I took it near a plasma globe (the type sold in party/toy stores). The meter showed 0.13 mcSv/h. Then I turned the lamp on and low and behold the meter jumped to 0.89 ...
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143 views

Characteristic waves in a plasma

What does "characteristic wave" mean in the context of plasma waves? For example, when propagating parallel to the plasma magnetic field, the characteristic wave is circularly polarized. Does this ...
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63 views

Minimum number of interacting particles to form a plasma

After reading this question What is the minimum number of electrons necessary to propagate a plasmon? I began to wonder what is the minimum number of particles needed to have a plasma? I figure that ...
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260 views

Why do many books say quasineutrality is needed for a plasma to exist?

Many books on plasma physics (Chen, Goldston, Lieberman) say that quasineutrality must be satisfied for the matter in question to be a plasma. Yet, we know that non-neutral plasmas exist. So why do so ...
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116 views

Why is the collision term negative in the equation of motion for a fluid of electrons in a plasma?

The fluid equation of motion for electrons in a cold plasma is \begin{equation} m_en_e\frac{d\textbf{v}}{dt} = -en_e(\textbf{E}+\textbf{v}\times \textbf{B}) - m_en_e\nu\textbf{v} \end{equation} where ...
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Is there a phase transition between a gas and plasma?

Does a phase transition occur as a gas is heated to create a plasma? If so, is this a first or second order phase transition? Also, does the presence of a phase transition depend on the pressure or ...
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Can plasma turn back into gas, solid, or liquid?

I wanted to know if, since basic chemistry teaches you that states of matter can be changed, I was wondering particularly about plasma. I know that virtually all of the Sun is plasma, so I was ...
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4k views

Why is lightning considered a plasma?

I was wondering why a lightning bolt is coined as "plasma", or a "spark" from an electrical wire/device is as well, yet flares, molten lava, and burning buildings are not(flares are pyrotechnic, ...
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152 views

Max temperature that can be obtained from radiation source when nonlinear interaction with matter is important?

Using a black body radiation as furnace it is usually said that the max achievable $T$ is limited to the T of the source. So a source of 3000K can not be used to heat a body above 3000K. A long ...
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889 views

Is a plasma a distinct phase of matter?

Long ago I learned that a plasma was a distinct state of matter after solid, liquid and gas, and also that it was achieved by imparting heat to a the matter. But most references describe a plasma as ...
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How to tell theoretically whether an electron behaves as wave or particle

I have seen many questions on SE on the dual nature of electrons behaving in certain circumstances as particles and as waves in some other circumstance. There is one thing I couldn't get a clear ...
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177 views

plasma frequency in non-neutral plasma

Is it possible to see the oscillations with plasma frequency in a gas of particles of the same charge (not mixture of positive and negative charges)?
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What state is fire? Solid, Liquid or Gas or Plasma? [duplicate]

What state is fire? Solid, Liquid or Gas or Plasma? I was just roaming around when this question popped out of my mind. In what state is FIRE?
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16k views

Transverse Magnetic (TM) and Transverse Electric (TE) modes

I'm reading and working my way through "Plasmonics Fundamentals" by Stefan Maier and I've come across a step in the workings that I'm struggling to understand when working out the electromagnetic ...
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219 views

Could I use an electron gun to make plasma?

Could I ionize a gas using an electron gun and knock off electrons in the gas to make plasma?
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86 views

Can be the ionosphere described as an elecro-magnetic field?

I read that the ionosphere can be defined as plasma. it has its plasma frequency it has its Debye length it is overall neutral As it is overall neutral it does not produce any electric field. ...
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50 views

Under what conditions is it possible to ionize atoms using an electron gun?

Using the electron bombardment method, if I wanted to ionize, for example, Xenon gas electrons with an electron gun, under what conditions is it possible to do so? (Heat, pressure?)
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203 views

$E\times B$ drift of a single particle in vacuum with unifiorm $E$ and $B$

The force on a charged particle in electric field $E$ and magnetic field $B$ is given by: \begin{equation} m \dot{v} = q ( E + v \times B) \end{equation} Then, the $E \times B$ drift velocity $v_E$ ...
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821 views

Would an octahedral magnet work as a magnetic bottle?

First, let me see if I understand all this: Charged particles are curved by magnetic fields, so if the magnetic field is strong enough, the particles "follow" the magnetic field lines, in N or S ...
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Intensive radiative heat transfer in very hot gas ( >5000K, gas core nuclear reactor related )

The question: At temperatures above ~5000K are not stable any solid or liquid materials or even more complex molecules (such as fullerenes and Polycyclic aromatic hydrocarbons) which emit/absorb ...
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Plasma Propulsion system - Maximum Velocity [closed]

What is the maximum velocity that can be achieved using plasma propulsion if we could make a propulsion system as powerful as lightning ?
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311 views

Apart from Alfvenic turbulence, what is the most important unsolved problems in plasma physics? [closed]

Apart from Alfvénic turbulence, what is the most important unsolved problems in plasma physics? Is there a review article describing some important unsolved problems in plasma physics, I repeat, ...
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2k views

What is electron density and its unit in plasma physics?

I can not find (through Google search engine) that what means electron density and what is its unit? and what is there relation between electron density and electrical conductivity?
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Jupiter radiation belt: where >MeV particles comes from?

When I read some discussion about exploration of Jupiter moons, or possibility of life there, a common argument is high dose of radiation in Jupiter's radiation belt (several orders of magnitude ...
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322 views

simple MHD simulation code for (self) education and play with [closed]

I would like some super simple computational code for solving magnetohydrodynamics problems. High accuracy nor performance is not my concern. I wan't it just to visually explore qualitative behavior ...
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117 views

Astronomical-wavelength radio (AWR) transmissions between cosmic plasmas?

My son asked me if electromagnetic waves longer than radio exist. I told him that even though physics permits such waves, there are no antennas long enough to radiate or detect them. However, on ...
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61 views

Does phase lead or lag in a plasma?

Plasmas have an index of refraction less than 1. So say you sent one beam of light through a plasma and another one along a path just as long but in free space. Is the plasma beam's phase lead or lag ...
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214 views

Application of plasma actuators for flow control of moving objects

I've recently been to a converence on plasma physics were, to my surprise, a lot of presentations were concerned with plasma actuator. Could someone, preferably in the field, tell me how long people ...
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What causes fluorescent light bulb to light up when it is near a plasma globe? Can this phenomenon be used to generate electricity in a circuit?

When a fluorescent light bulb is placed near a plasma globe, despite the fact there isn't a closed circuit, a part of the light blulb would light up. I tried measuring the voltage of the air ...
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172 views

Plasma Stability

Plasma consists of positive(ions) and negative(electrons) charges. Ions repel each other, so do the electrons, in the mean time ions attract electrons and vice versa, what will be the net result? Does ...
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Can low temperature plasma exist?

Plasma is ionized gas which as far as I know only occurs at high temperatures. When plasma cools down it tends to recombine with the electrons present and turn back into gas. But what if the ...
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218 views

What are the problems in quark-gluon plasma? [closed]

Someone (T.D.Lee?) said that quark-gluon plasma would (after 1980?) be very important to understand high-energy physics experiments. I read some description of this new state in wikipedia ...
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438 views

Why not an Electric Theory of Everything? [duplicate]

Possible Duplicate: How to debunk ‘The Electric Universe’? I am just wondering why there exists such a strong feeling within the physics community against theories such as Plasma Physics ...
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381 views

Effect of electric field of plasma sheaths

How will an electric fields affect the formation of plasma sheaths?
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53 views

Are the ions in a fluorescent lamps concentrated near the electrodes?

Are the ions in a fluorescent lamps concentrated near the electrodes , and just the electrons move to the other electrode or the positive mercury ions move too?
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24k views

Is Keshe's technology for real?

http://www.youtube.com/watch?feature=player_embedded&v=UrN99RELqwo They clain they can create free energy using plasma reactors. Is this fake? M.T. Keshe said that several entities, ...
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328 views

What causes the structure visible in first few milliseconds of a nuclear explosion?

Following on from this question, here is a high-speed photograph of a nuclear explosion, taken about 1 ms after detonation: (source) As anna v pointed out, several similar images can be seen in a ...
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212 views

Would it be possible to have an electron-less solid?

We can create plasmas quite easily, indeed you can buy a plasma cutter and generate it all day long for less than $500. Would it be possible to trap a plasma, say magnetically, and cool it so much ...
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Voyager 1 cosmic ray strips

In the last months Voyager 1 has experienced a dramatic drop in the cosmic ray radiation, which was been exceptionally uniform for the last 10 years, except for the past july 28 and august 14 events, ...
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Does Fire Conduct Electricity? Why?

Recently, I have stumbled upon a YouTube video by Veritasium describing the conductivity of fire. My question is: how exactly does fire conduct electricity? I am a high school student; therefore ...
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1k views

Possible colors of fire?

I have learnt that depending on the various gases those are involved in the reaction that produces fire, different colors (yellow, red or blue) of flames become visible. I have a question .. what are ...
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4answers
334 views

what is the basic form of the 'fire'? [duplicate]

Possible Duplicate: Is fire matter or energy? What is the basic form of fire? physics defines every entity by a basic form either solid or liquid or as a gas, example: water is liquid, ice ...
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552 views

Why doesn't a neon sign seem that hot?

I heard that neon signs contain plasma, why aren't they hot? is it because the electrons and ions do not hit the lamp's wall? Is it because it is non thermal plasma and electrons and ions are not in ...
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What velocity must an aircraft achieve for its shock wave to transform to plasma?

A follow-up to After what speed air friction starts to heat up an object? I understand there may be technological limitations at present ... but, is it theoretically possible for a body to travel ...
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What is non-thermal plasma?

I read about non-thermal plasma, but I still have some questions: The ions and neutral particles are not in thermal equilibrium with the electron, does that mean that the overall temperature is low ...