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Topic: Plasma frequency


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In the News (Mon 16 Nov 09)

  
  CHEMTRAILS - CONTRAILS
In order to arrive at the plasma frequency for the current state of the atmosphere, it is essential to determine an estimate for the electron density of the atmosphere under its current and altered state.
The plasma frequency is intimately dependent upon the electron density; it is, in fact, proportional to the square root of this electron density.
It is of more than passing interest that the plasma frequency of a solid metal is also related directly to its 'transparency' with respect to the electromagnetic frequencies to which it is subjected.
www.carnicom.com /plasma1.htm   (1250 words)

  
 The Future in Energy is Through Plasma Research   (Site not responding. Last check: 2007-11-04)
Plasma physics is the branch of science that studies the properties and applications of plasma.
Plasma thrusters for propulsion in space can eject their propellant at much higher velocities than a chemical rocket, so that less mass need be expended.
In this device, a plasma is heated by the energy source and allowed to expand through a channel located in a magnetic field perpendicular to the direction of expansion; this produces an electromotive force perpendicular to the directions of both the magnetic field and the expansion.
www.infoimagination.org /ps/plasma   (1890 words)

  
 Plasma wave tube - Patent 4916361
The plasma wave tube of claim 17, said electron beam generating means each comprising a chamber communicating with the interior of said waveguide housing, a cold-cathode extending into said chamber, and means for applying a voltage signal to said cold-cathodes, said chamber enabling a flow of plasma the waveguide stimulate electron emission from the cold-cathode.
Plasma is generated within the waveguide by a cold-cathode discharge struck between the waveguide 2, which serves as the cathode electrode for this purpose, and the fine-wire anodes 4.
A plasma is also established adjacent cold-cathodes 72 and 74 by wire-anode discharge 84 and 86, respectively, so that counterpropagating electron beams 88 and 90 are directed into the waveguide plasma to drive counterpropagating electron plasma waves, and couple nonlinearly with these waves to generate an electromagnetic waveguide mode at twice the plasma frequency.
www.freepatentsonline.com /4916361.html   (5107 words)

  
 Markland Technologies: Gas Plasma
The vertical separation is taken to be while the lateral separation is taken to be The plot has the curves for the perfectly conducting case (high plasma frequency and density) along with those for several values of the plasma frequency, which depends on plasma density.
Plasmas have a much wider range of power capability than metals as evident from low powered plasma in fluorescent bulbs to extremely high-powered plasmas in the Princeton University experimental fusion reactors.
One option is to construct controlled density plasma blankets around plasma antennas thereby creating windows (low-density sections of the blanket) for main lobe transmission or reception and closing windows (high-density regions in the plasma blanket).
www.marklandtech.com /technology_portfolio/gasplasma4.html   (1138 words)

  
 The plasma frequency
Clearly, there is a different plasma frequency for each species.
However, the relatively fast electron frequency is, by far, the most important, and references to ``the plasma frequency'' in text-books invariably mean the electron plasma frequency.
It should be noted that, despite the conventional requirement (9), plasma physics is capable of considering structures on the Debye scale.
farside.ph.utexas.edu /teaching/plasma/lectures/node6.html   (324 words)

  
 PEPL - Resonance Probe
The resonance probe (also known as the plasma frequency probe or RF impedance probe) technique is used to measure the absolute electron density of a plasma.
Plasma electrons have a natural resonant frequency known as the electron plasma frequency which depends on the plasma density.
When the resonance probe is immersed in the plasma and driven by an RF sweep frequency, the reactance of the antenna/probe becomes zero at the plasma frequency.
www.engin.umich.edu /dept/aero/spacelab/diagnostics/res_probe.html   (805 words)

  
 ESTIMATION OF ELECTRON DENSITY OF IONOSPHERIC PLASMA USING WAVE, IMPEDANCE AND TOPSIDE SOUNDER DATA
Plasma emissions in the band (fp,fu) were prominent when propagation properties of electromagnetic excitation were dominating (topside sounder) or if the excitation introduced a sufficient amount of nonequilibrium components into the plasma in the form of an injected electron beam.
In order to minimize effects resulting from plasma depletion by the satellite body and solar panels and from corrections due to the sheath and magnetoplasma directivity, the data registered in dense plasma when the satellite has a velocity component away from the sun are analyzed.
The notions of susceptibility of the plasma to radiate in this band and the high input impedance of wave instrument resulted in the assumption that the voltage spectrum inside the instrument is directly related to the spectrum of the voltage which drives the circuit.
www-ssc.igpp.ucla.edu /IASTP/93   (5872 words)

  
 Status and Problems of Plasma Accelerators
To be used for acceleration, the phase velocity of the plasma wave should be nearly equal to the particle velocity, which is the light velocity for light particles, such as electrons.
As a result of the whole sequence, the laser frequency is modulated by the plasma frequency, which is shown in the right figure.
It requires a fine control of the plasma density; the plasma frequency has to be tuned so as to be exactly equal to the laser beat frequency.
icfa-usa.jlab.org /archive/newsletter/icfa_bd_nl_12/node26.html   (4079 words)

  
 Theory   (Site not responding. Last check: 2007-11-04)
The ion cyclotron frequency in CAT for a hydrogen plasma is near 1.3 MHz.
The most efficient place to heat the plasma is at the center so the energy doesn't escape right away, so launching a slow wave this way is unsatisfactory for plasma heating.
The fast wave is not under the same restriction as the slow wave; it is free to penetrate the plasma, but then fast waves don't heat plasmas, so the result is that you can't directly heat plasmas by simply launching a slow wave into the plasma at the ion cyclotron frequency.
www.physics.auburn.edu /~plasma/fusion/fusion_lab/cat/icrf/theory.html   (503 words)

  
 Radio frequency plasma generator - Patent 4792732
In accordance with the present invention, the electrons in a plasma are excited to a precise uniform energy level by means of a circularly polarized electric field of a specified frequency and magnitude.
A resultant circularly polarized field of a precise frequency and magnitude is formed in the space in the container to excite the electrons in the gas to a precise and uniform energy level.
For a given molecular density, the lower field strength and frequency are both easier to generate and apply to a gas; or for the same field strength and frequency, it is possible to operate at much higher molecular densities which extends the range of operation in comparison to the linear type of excitation.
www.freepatentsonline.com /4792732.html   (2529 words)

  
 Plasma Rotation Experiment   (Site not responding. Last check: 2007-11-04)
Plasma photons are collected outside the optical window by a 7.5 cm diameter lens (f=10 cm) on a movable slide.
The lock-in is referenced to the 30 KHz chopping frequency and discriminates the induced fluorescence signal.
The center frequency of the LIF signal at this point is the reference for v=0.
www.physics.auburn.edu /~plasma/fusion/fusion_lab/cat/protation.html   (1023 words)

  
 Plasma (physics) - Wikipedia, the free encyclopedia
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).
Plasma temperature is commonly measured in Kelvin or electron volts, and is (roughly speaking) a measure of the thermal kinetic energy per particle.
The dynamics of plasmas interacting with external and self-generated magnetic fields are studied in the academic discipline of magnetohydrodynamics.
en.wikipedia.org /wiki/Plasma_(physics)   (3938 words)

  
 NASA - IMAGE - Radio Plasma Imager (RPI)   (Site not responding. Last check: 2007-11-04)
The RPI instrument is a low-power radar which operates in the radio frequency bands which contain the plasma resonance frequencies characteristic of the Earth's magnetophere (3 kHz to 3 MHz).
RPI can locate regions of various plasma densities by observing radar echos from the plasma that are reflected where the radio frequency is equal to the plasma frequency.
By stepping through various frequencies for the transmitted signal, features of various plasma densities can be observed and, by fitting contours and/or magnetospheric models to the features, a 3-D specification of the shape of the magnetosphere can be created.
image.gsfc.nasa.gov /rpi   (164 words)

  
 Plasma oscillation - Wikipedia, the free encyclopedia
In physics, plasma oscillations, often referred to as "Langmuir waves" or "plasma waves," are periodic oscillations of charge density in conducting media such as plasmas or metals.
Since the frequency is independent of the wavelength, these oscillations have an infinite phase velocity and zero group velocity.
In a bounded plasma, fringing electric fields can result in propagation of plasma oscillations, even when the electrons are cold.
en.wikipedia.org /wiki/Plasma_frequency   (431 words)

  
 Aerosol Operation Crimes & Cover Up
A plasma is an electrically conductive gas; considerable evidence now exists that our atmosphere now exists in that state as a result of the aerosol operations that have been conducted openly without consent for more than five years.
The model is based upon an examination of plasma physics and the propagation of electromagnetic energy within a plasma state.
The plasma frequency, or the "resonant" frequency of the electrically conductive gas, plasma, or atmosphere in this case.
www.carnicom.com /ke1.htm   (1397 words)

  
 Frequently Used Terms in Space Plasma Physics   (Site not responding. Last check: 2007-11-04)
For a plasma in a magnetic field, a compression slow enough that the magnetic moment (and other adiabatic invariants - see entry) of the plasma particles may be taken as constant.
The waves have frequency significantly less than the ion cyclotron frequency, and are characterized by the fact that the field lines oscillate (wiggle) with the plasma.
Plasmas are further characterized by relatively large intermolecular distances, large amounts of energy stored in the internal energy levels of the particles, and the presence of plasma sheaths at all boundaries of the plasma.
utd500.utdallas.edu /~kivanc/index_fut.html   (4771 words)

  
 VLF Plasma Waves
As the spacecraft approaches the source field line, the higher frequencies are detected first, thereby producing the "funnel-shaped" frequency-time signature that is the characteristic feature of the auroral hiss spectrogram.
This cutoff is a propagation effect that occurs because the whistler mode has an upper frequency limit of either the electron plasma frequency or the electron cyclotron frequency, whichever is smaller.
The wideband receiver is configured to obtain data in the frequency range of 250-340 kHz and is connected to the electric Eu antenna.
www-istp.gsfc.nasa.gov /istp/polar/polar_pwi_descs.html   (1369 words)

  
 Plasma Recovery - Blood Plasma Recovery - PlasmaRecovery.com
In the technique of plasma immersion ion implantation, plasma ions are implanted into a target upon pulsed charging to high negative voltages.
Then, unless the delay time between pulses is large enough to allow for a complete recovery of the plasma, the conditions of the plasma from which ions are drawntowards the target are changed, and so is the implantation current [5].
region of the plasma has not recovered from the previous highvoltage pulse; as it is still depleted of ions due to incomplete plasma recovery, the newly established matrix ion sheath at the beginning of the next pulse incorporates insufficiently many ions to accelerate towards the target.
www.plasmarecovery.com   (2988 words)

  
 Excitation of Oscillations of a Magnetized Collisionless Plasma
In most basic treatments of plasma physics, the motion of charged particles in electro-magnetic fields is considered only in an incomplete way, since the effect of internal fields produced by collective displacements of plasma electrons is neglected within the equation of motion.
On the other hand, the equation for plasma oscillations is always derived only one dimensionally, therefore being inappropriate for anisotropic media as in the case of a magnetized plasma.
Therefore, no propagation of plasma disturbances across the magnetic field is possible, which enables then a local resonant excitation of plasma oscillations under the above restrictions (which, however, can be considered to hold for instance for all realistic cases of radio wave propagation and absorption in the ionosphere).
www.plasmaphysics.org.uk /papers/plasmaosc2.htm   (3735 words)

  
 PHYS 515: Course Calendar
Subjects: Ratios expressed in terms of the plasma parameter, plasma frequency, solar type III bursts.
Question: Calculate the collision frequency and mean free path for the five plasmas we considered before, i.e.
Subjects: Plasma waves: cyclotron waves, resonance at cyclotron frequency, cut-off at plasma frequency.
solar.physics.montana.edu /martens/plasma/calendar.html   (1218 words)

  
 Plasma Plus II Frequency Generator
The Plasma Plus II is an experimental high voltage frequency generator.
The Plasma Plus II has a variable duty cycle control which allows you to select duty cycle ranges from 2% to 98%.
This is achieved with an internal circuit which automatically adjusts the duty cycle as frequencies change.
www.plasmaplus.net   (531 words)

  
 Metals, X-rays, and plasma frequency
I was wondering if it would be fair to say that the frequency at which x-rays start to penetrate a metal would be the plasma frequency associated with the electron density of the metal, i.e.
If you are trying to calculate the frequency at which a metal starts to become transparent to radiation, that would be the plasma frequency.
...it would be fair to say that the frequency at which EM radiation starts to penetrate a metal would be the plasma frequency associated with the electron density of the metal...
www.physicsforums.com /showthread.php?t=117662   (569 words)

  
 Plasma Physics
If we start with a gas of neutral atoms, we create a plasma by removing an electron from an atom, leaving a positive ion.
plasma region is field free and approximately neutral
Another reality check: is the plasma frequency for these conditions greater than the incident frequency ?
www.uccs.edu /~tchriste/courses/PHYS549/549lectures/plasma.html   (628 words)

  
 System 8CE EM+ Radiant Plasma Resonant Frequency Generator
This unique plasma resonance optimization circuitry approach and plasma resonance dynamics peaking capability was our innovation in December of 1997, implemented on the earliest versions of the EM+ resonant radiant plasma systems I designed.
About 100 of the most commonly used frequencies have been built and are available on the CD that is sent with the system, along with some suggestions of software you can use in building more of your own.
While the published frequency lists are a valuable reference and 'starting point' in trying to determine what frequencies might be most helpful to a specific 'research volunteer' on a specific occasion, the addition of these testing techniques may help researchers to achieve greater effectiveness.
www.stenulson.net /althealth/em8ce.htm   (5110 words)

  
 ALTERNATIVE HEALTH APPROACHES, Radiant Plasma Resonant Frequency Generators, Zappers, Colloidal Silver Info, Books, & ...
Research reports tell us that a wide variety of these various resonant frequency generating devices are alleviating a wide range of conditions, from colds and flu, to parasite infestation, to chronic sinus infections, yeast infections, and including Lyme disease, HIV, and Cancer in some cases.
Click Here for information on the latest enhancements for the SYSTEM 8CE EM+ Resonant Radiant Plasma Frequency Generator Research Systems which are capable of interfacing with laptop and desktop computers as well as with a wide variety of programmable frequency generators, such as Patrick Robin's F125.
A 'Zapper' is a resonant frequency generating device, and is used to induce resonances into the body by contact- resonances that, while disruptive to pathogens, are not harmful to your body's healthy cells.
www.stenulson.net /althealth/index.htm   (2316 words)

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