# PRINCESS

## Plasma Property Calculator

In the early 1990s, Prof. Edgar Choueiri wrote a program, PRINCESS, to graphically display a number of characteristic lengths, frequencies, and velocities for a user-defined plasma (input variables included density, electron and ion temperatures, species of gas, and magnetic field magnitude). Recently, an updated and interactive version of this program, PRINCESS II, was developed in Mathematica. This new form offers a few major improvements over the original PRINCESS. It is dynamically interactive, can be accessed on any platform (Mac or PC) provided the user has version 6.1 or newer of Mathematica, and new characteristic lengths, frequencies, and velocities can be added easily by following the template in the source code.

As shown in Figure 1, the user varies the plasma parameters (including $$\alpha$$ the ionization fraction) at the left side of the panel while the corresponding characteristic values, marked with pin plots in the right panel, change in real time. Toggling the tabs to frequencies, velocities, and lengths will change the displayed characteristic values in the right hand panel. This output can also be copied and pasted for publication purposes.

This work was supported by NSF grant ATM-0411392.