In the Mirror and Cusp Plasma Machine the plasma is produced using Electron Cyclotron Resonance Heating (ECRH), with a variable microwave power with a maximum power of 5 kW with a frequency of 2.45 GHz. This device uses two solenoidal magnets parallel to one another to provide the magnetic field. The coils can be run with complementary or opposing fields. Hence, it is possible to run the device either as a simple mirror or as a spindle cusp, which is an advantage over other conventional devices of this kind. The water cooling coils could carrier currents maximum 610 ADC. When the incident microwave source frequency is equal to the cyclotron frequency, ECRH will be formed. In our Plasma Machine, the microwave heating source is:
w resonance = 2.45 GHz
B resonance = 0.0875 Tesla or 875 Gauss
When the movable coils are located in their closet position of 30 cm between the centers of the coils, the mirror ratio is 1.15.
This machine has the advantage of magnetically confine stable plasma and the main goal of this project will be to built and develop new diagnostics probe for plasma research experiments.
Advanced Analyzers and Probes for Fusion-Plasma Diagnostics
Various novel analyzers and probes were designed, built and successfully tested in the Cusp-Mirror machine in the Fusion Research Laboratory at University of Missouri-Columbia and can be used at PUPR Plasma Engineering Laboratory :
The Variable Energy Analyzer (VEA),
the Magnetic Dipole Moment Meter (The æ-Meter),
The Double Energy Analyzer (DEA), and
the Hyperbolic Energy Analyzer (HEA).
The main advantage of these analyzers is that they are very small (about 7-mm diameter) and they are made of materials that resist high temperature, high plasma flux and they are shielded for RF signals. All of them have a probe driver in such way that they can move back and forward inside the machine. For that reason is possible map the plasma inside almost all points inside the device.
Dycor Dymaxion Mass Spectrometer
Dycor Dynamaxion mass spectrometer is a compact quadrupole mass spectrometer capable of distributed control and simultaneous multiplexing analyzer head locations from a single PC. The quadrupole mass spectrometer allows you to identify the masses of individual atoms and molecules that have been converted to ions from a given sample. This technique is unique in that it provides a fingerprints identification for the structural and chemical properties of these molecules. The mass spectrometer is one of a specialized subset of mass spectrometers that measure background gases in an existing vacuum chamber.
Data Acquisition System
One of the fundamental technique for measuring the properties of the plasma is the use of the electrostatic probes. Placing a small probe into the plasma and observing the current to the probe as a function of the
difference between the probe and the plasma space potential can determine the basic plasma parameters.