Plasma Critical Density | A Plasma Science Parameter: The plasma critical density is a crucial parameter in plasma science. This parameter reflects the density at which free electrons become trapped.
It is also called the turning point radius. It is derive using the classical theory of the bound electron, which is in good agreement with experimental results from the ORION experiment. This theory is applicable to other multi-electron ions, as well.
Plasma Critical Density | A Plasma Science Parameter
Numerical Simulations Of Plasmas
Various numerical simulation methods have been developed to study the dynamics of plasma critical density. One of them is a full simulation, which captures all the details of the pump-plasma interaction.
Another method, known as a moving window simulation, reduces the computational cost by only calculating the pump-plasma interaction for a single set of parameters. The main challenge with reduced simulations is the accurate representation of the plasma and laser conditions at the leading edge of the simulation domain.
Laser Ponderomotive Force
The ponderomotive force is the result of the plasma’s interaction with a laser pulse. The laser’s high intensity induces a high plasma thermal pressure. This pressure causes a fast acceleration of the plasma. The plasma’s critical density is 3.8 ps.
The electric field of the plasma is a strong quasi-static field. This electric field is generated at the expansion front of the heated bulk plasma within the laser spot. This electric field, coupled with the magnetic field, contributes to the E x B drift.
Temperature ramps are an important factor in plasma critical density measurement. The characterization of these ramps is essential for understanding the proper beam-plasma interaction. Further research is needed to better understand how these ramps evolve over time.
Effects Of Nanostructure Morphology On Absorption Efficiency
Plasma critical density absorption efficiency is increase in the presence of nanostructures. Compared to homogeneous plasma, these nanostructures have higher ion absorption efficiencies, which is a major advantage for laser-driven ion acceleration. Nanowire arrays, foams, and random nanowire assemblies exhibit high absorption efficiencies and are therefore of interest for laser-driven ion acceleration.
Iodine laser is a method that increases plasma critical density by ionizing a plasma with a chemically-induced singlet delta oxygen. This type of laser is operate at a low gas pressure and has a short run-time.
However, the iodine laser has a number of drawbacks, and it is not a pollution-free process. Also, it does not have a very high power. In order to achieve its full potential, a non-chemical SDO generator is require. Electric discharge plasma has been studied as a possible non-chemical SDO source.
Gemini-Laser Interaction With Critical Density Plasma
The Gemini-laser interaction with this type of plasma enables the measurement of the electron and proton maximum energies simultaneously. A double-layer target coated with near-critical density carbon foil and a Gemini laser pulse is used. The laser pulse is relativistic and significantly enhances the maximum energies of electrons and protons.