Plasma (physics)

plasmaplasma physicsplasmasionized gasplasma physicistplasma sourceionised gasionized plasmaplasma stateChemical plasma
Plasma is one of the four fundamental states of matter, and was first described by chemist Irving Langmuir in the 1920s.wikipedia
1,525 Related Articles

Phase transition

phase transitionsorder parameterphase change
Plasma and ionized gases have properties and display behaviours unlike those of the other states, and the transition between them is mostly a matter of nomenclature and subject to interpretation.
The term phase transition (or phase change) is most commonly used to describe transitions between solid, liquid, and gaseous states of matter, as well as plasma in rare cases.

Sun

solarSolThe Sun
The interior of the Sun is an example of fully ionized plasma, along with the solar corona and stars.
It is a nearly perfect sphere of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process.

Lightning

lightning boltlightning strikelightning strikes
Neon signs and lightning are examples of partially ionized plasma.
Lightning creates light in the form of black body radiation from the very hot plasma created by the electron flow, and sound in the form of thunder.

Corona

solar coronacoronal heating problemcoronae
The interior of the Sun is an example of fully ionized plasma, along with the solar corona and stars.
A corona (Latin, 'crown') is an aura of plasma that surrounds the Sun and other stars.

Temperature

temperaturesair temperaturewarm
Based on the surrounding environmental temperature and density, partially ionized or fully ionized forms of plasma may be produced.
physical properties of materials including the phase (solid, liquid, gaseous or plasma), density, solubility, vapor pressure, electrical conductivity

Magnetosphere

magnetotailmagnetosphericmagnetic field
The Earth's ionosphere is a plasma and the magnetosphere contains plasma in the Earth's surrounding space environment.
Farther out, field lines can be significantly distorted by the flow of electrically conducting plasma, as emitted from the Sun or a nearby star.

Solid

solidsssolid state
The plasma state can be contrasted with the other states: solid, liquid, and gas.
Solid is one of the four fundamental states of matter (the others being liquid, gas, and plasma).

Intracluster medium

intracluster gasgasICM
Plasma is mostly associated with stars, extending to the rarefied intracluster medium and possibly the intergalactic regions.
In astronomy, the intracluster medium (ICM) is the superheated plasma that permeates a galaxy cluster.

Gas

gasesgaseousg
The plasma state can be contrasted with the other states: solid, liquid, and gas.
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).

Plasma oscillation

plasma frequencyplasmon frequencycharge density waves
3) Plasma frequency: The electron plasma frequency (measuring plasma oscillations of the electrons) is large compared to the electron-neutral collision frequency (measuring frequency of collisions between electrons and neutral particles). When this condition is valid, electrostatic interactions dominate over the processes of ordinary gas kinetics.
Plasma oscillations, also known as Langmuir waves (after Irving Langmuir), are rapid oscillations of the electron density in conducting media such as plasmas or metals in the ultraviolet region.

Plasma etching

plasma etchplasmaplasma etchant
The response of plasma to electromagnetic fields is used in many modern technological devices, such as plasma televisions or plasma etching.
It involves a high-speed stream of glow discharge (plasma) of an appropriate gas mixture being shot (in pulses) at a sample.

Ionosphere

ionosphericionospheric physicsD layer
The Earth's ionosphere is a plasma and the magnetosphere contains plasma in the Earth's surrounding space environment.
This portion of the atmosphere is partially ionized and contains a plasma which is referred to as the ionosphere.

Lyman Spitzer

Lyman Spitzer Jr.Lyman Spitzer, Jr.Spitzer, Lyman
The term fully ionized gas introduced by Lyman Spitzer does not mean the degree of ionization is unity, but only that the plasma is in a Coulomb-collision dominated regime, i.e. when, which can correspond to a degree of ionization as low as 0.01%.
As a scientist, he carried out research into star formation, plasma physics, and in 1946, conceived the idea of telescopes operating in outer space.

Universe

physical worldthe universeuniverses
Plasma may be the most abundant form of ordinary matter in the universe, although this hypothesis is currently tentative based on the existence and unknown properties of dark matter.
During this period, the Universe was still far too hot for matter to form neutral atoms, so it contained a hot, dense, foggy plasma of negatively charged electrons, neutral neutrinos and positive nuclei.

Debye length

Debye-lengthDebye screening lengthDebye-Hückel screening
This results in the important concept of "quasineutrality", which says the density of negative charges is approximately equal to the density of positive charges over large volumes of the plasma, but on the scale of the Debye length there can be charge imbalance.
In plasmas and electrolytes, the Debye length (also called Debye radius), named after Peter Debye, is a measure of a charge carrier's net electrostatic effect in solution and how far its electrostatic effect persists.

Double layer (plasma physics)

double layerdouble layersVlasov–Poisson equation
In the special case that double layers are formed, the charge separation can extend some tens of Debye lengths.
A double layer is a structure in a plasma consisting of two parallel layers of opposite electrical charge.

Debye sheath

Bohm sheath criterionplasma sheathsheath
If an electrode is inserted into a plasma, its potential will generally lie considerably below the plasma potential due to what is termed a Debye sheath.
The Debye sheath (also electrostatic sheath) is a layer in a plasma which has a greater density of positive ions, and hence an overall excess positive charge, that balances an opposite negative charge on the surface of a material with which it is in contact.

Boltzmann relation

A common example is to assume that the electrons satisfy the Boltzmann relation:
In a plasma, the Boltzmann relation describes the number density of an isothermal charged particle fluid when the thermal and the electrostatic forces acting on the fluid have reached equilibrium.

Chemistry

chemistchemicalChemical Sciences
This also can be accompanied by the dissociation of molecular bonds, though this process is distinctly different from chemical processes of ion interactions in liquids or the behaviour of shared ions in metals.
Less familiar phases include plasmas, Bose–Einstein condensates and fermionic condensates and the paramagnetic and ferromagnetic phases of magnetic materials.

Magnetohydrodynamics

magnetohydrodynamicMHDmagneto-hydrodynamics
The dynamics of plasmas interacting with external and self-generated magnetic fields are studied in the academic discipline of magnetohydrodynamics.
Examples of such magneto­fluids include plasmas, liquid metals, salt water, and electrolytes.

Irving Langmuir

LangmuirI. LangmuirLangmuir, Irving
Plasma is one of the four fundamental states of matter, and was first described by chemist Irving Langmuir in the 1920s.
He was one of the first scientists to work with plasmas, and he was the first to call these ionized gases by that name because they reminded him of blood plasma.

State of matter

states of matterstatephysical state
The plasma state can be contrasted with the other states: solid, liquid, and gas. Plasma is one of the four fundamental states of matter, and was first described by chemist Irving Langmuir in the 1920s.
Four states of matter are observable in everyday life: solid, liquid, gas, and plasma.

Waves in plasmas

plasma waveplasma waveswaves
In plasma physics, waves in plasmas are an interconnected set of particles and fields which propagate in a periodically repeating fashion.

Outer space

spaceinterstellar spaceintergalactic medium
Plasma is mostly associated with stars, extending to the rarefied intracluster medium and possibly the intergalactic regions.
Outer space is not completely empty—it is a hard vacuum containing a low density of particles, predominantly a plasma of hydrogen and helium as well as electromagnetic radiation, magnetic fields, neutrinos, dust, and cosmic rays.

Electron temperature

The degree of plasma ionisation is determined by the electron temperature relative to the ionization energy (and more weakly by the density), in a relationship called the Saha equation.
If the velocities of a group of electrons, e.g., in a plasma, follow a Maxwell–Boltzmann distribution, then the electron temperature is defined as the temperature of that distribution.