Relativistic Ohms Law: Modeling 1D Hot Electron Beam in Plasma

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SUMMARY

The discussion focuses on modeling a one-dimensional hot electron beam interacting with a charge-neutral plasma using specific equations derived from relativistic principles. The equations include the relativistic momentum equation, continuity equation, and an electric field evolution equation, which incorporate parameters such as electron charge (e), mass (m), resistivity (η), electron speed (v), and number density (n). The participants confirm that the equations are dimensionally consistent, affirming that the left-hand side represents acceleration, aligning with the right-hand side's Newtonian units. The conversation emphasizes the need for relativistic corrections to Ohm's Law in this context.

PREREQUISITES
  • Understanding of relativistic mechanics and equations of motion
  • Familiarity with plasma physics concepts, particularly charge neutrality
  • Knowledge of electromagnetic theory, specifically Ohm's Law
  • Basic proficiency in mathematical modeling and dimensional analysis
NEXT STEPS
  • Research relativistic corrections to Ohm's Law in plasma physics
  • Explore the derivation and implications of the continuity equation in plasma dynamics
  • Study the role of electric fields in plasma behavior and electron dynamics
  • Investigate numerical methods for simulating 1D plasma interactions
USEFUL FOR

Physicists, plasma researchers, and engineers involved in modeling electron dynamics in plasma environments, particularly those interested in relativistic effects and electromagnetic interactions.

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A colleague and I are looking at modelling a hot electron beam hitting a initially charge neutral plasma. Initially we're looking at the 1D problem, the equations we're using are:
[tex] \begin{array}{rcl}<br /> \gamma^{3}(v/c)\left(\frac{\partial v}{\partial t}+v\frac{\partial v}{\partial x}\right) & = & -\frac{e}{m}E \\<br /> \frac{\partial n}{\partial t}+\frac{\partial }{\partial x}(nv) & = & 0 \\<br /> \frac{\partial E}{\partial t}+\frac{E}{\eta\epsilon_{0}} & = & \frac{nev}{\epsilon_{0}}<br /> \end{array}[/tex]
where e is the charge on the electron, m is the mass of the electron, [itex]\eta[/itex] is the resistivity of the charge neutral plasma, v is the speed of the electrons, n is the number density of the electrons and E is the electric field produced by the electron beam. It was brought to our attention that Ohms law is not relativitically invariant but it is possible to make it so.

So my question is this, "Are the equations we have correct for a simple 1D model or do we need to change something?"
 
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in the sum on the left hand side of your first equation the units don't match.
 
Yes they do. [itex]\gamma[/itex] has no units, the [itex]\partial_{t}y}[/itex] and [itex]v\partial_{x}v[/itex] both have units of acceleration. The first is LT^(-2), and the other is LT-1(LT^-1/L)=LT^(-2).
The units on the RHS are Newtons (eE and m is mass), so that side is acceleration also.
 

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