I Separation of Plasma into positive nucleus and negative electrons

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The discussion centers on the feasibility of separating plasma into positive nuclei and negative electrons and containing them within a magnetic bottle. While electric fields can provide some separation, they are limited by the attractive forces between electrons and nuclei, especially in denser plasmas. Techniques such as powerful lasers, fast particles, and neutral beam injection are explored for temporarily achieving separation and heating plasma to necessary fusion temperatures. The conversation highlights the immense forces involved in maintaining separation and the challenges of overcoming electrostatic forces as particle numbers increase. Overall, while theoretically possible, practical separation of plasma components presents significant challenges.
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Im wondering if plasma is possible to be separated into a positive nucleus and negative electrons and contained within a magnetic bottle ?
If possible, what is the most efficient method of achieving it ?
 
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An electric field will provide some separation, but the electrons and nuclei attract each other so it won't give a good separation unless the plasma is pretty thin.

A powerful laser or a bunch of fast electrons or protons can separate them temporarily (as the electrons move much faster), this is used in plasma wakefield acceleration.
 
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Blaze said:
Im wondering if plasma is possible to be separated into a positive nucleus and negative electrons and contained within a magnetic bottle ?
If possible, what is the most efficient method of achieving it ?
That is the principle of magnetic confinement in which a gas is heated to hundreds or thousands of times the ionization energy of the nuclei. For example, the ionization energy of hydrogen is 13.6 eV, and hydrogen (and deuterium and tritium) are heated to temperatures (or kinetic energies) of 5 to 100 keV, in the case of a D+T plasma (optimal temperature ~50 keV for fusion. A pure D plasma would require heating to about 200 keV for fusion, and other plasmas require higher temperatures.

Plasma heating can be accomplished by an electrical discharge (high current), a rapidly increasing magnetic field (adiabatic (actually quasi-adiabatic) compression), and/or electromagnetic (e.g., microwave) heating.

For optimal heating one must consider the energy losses, which include recombination (and photon emission), bremsstrahlung radiation, other (cyclotron) radiation, neutral particle loss and conduction losses.

Update/edit: Neutral beam injection is another method of heating (and fueling) a plasma. Fuel atoms are ionized, the nuclei accelerated, then recombined with electrons prior to injection into plasma. Collisions of neutral atoms with electrons and nuclei ionize the neutral atoms and provide heating to the plasma. For stability, a plasma must be held neutral, i.e., the number of electrons must equal the total charges on the nuclei.
 
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Blaze said:
Im wondering if plasma is possible to be separated into a positive nucleus and negative electrons and contained within a magnetic bottle ?
What are you actually suggesting here? The definition of a plasma is that it has net neutral charge. If you split it then the resulting + and - charges can be channelled through rings (as in the LHC) and made to travel thousands of metres under the control of carefully shaped magnetic fields, if you want. It strikes me that starting with a plasma may not be the best way.
Did you have a particular experiment in mind?
 
I'm wondering whether the poster means the complete separation of protons and electrons into two separate populations, each in a magnetic bottle? That could be done for small numbers of particles, but the energy required to overcome the resultant electrostatic field forces would scale non-linearly with number.
 
sciFax said:
but the energy required to overcome the resultant electrostatic field forces would scale non-linearly with number.
Absolutely immense forces involved! Such forces (in molecules) allow steel cables to support huge loads and steel beams to support skyscrapers. And, in those cases, the electric forces only operate between local protons and electrons.
This Hyperphysics link will allow you to find the amount of force between any values of charge and any separation you may choose.
 
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sophiecentaur said:
Absolutely immense forces involved!
Yes, indeed. This is also one of the many facts conveniently swept under the rug by proponents of the silly Electric Universe "cosmology." Takes all sorts.
 
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