Square of electric field and process used

Can anyone explain how can we calculate the magnitude of electric field at a point on the surface of a gold/silver particle? We can simulate the square of electric field and we get a color mapping of it with the scale at the bottom. But how can we exactly make out with color shade is it compared to scale at that point. Moreover the magnitude numbers shows below on the scale, what are its units? what are those numbers taken in reference to?

1. Hi.

At present, the tool reports the result of the calculation (magnitude of the E field) graphically. One can read/estimate the numerical value by comparing the color of the 2D-plot with the ruler below the plot.

As you mention, it would be nice to report the value of E^2 at specific locations or even regions of the system, namely, on the surface of the sphere.

These features need further development of the tool and will be considered immediately.

The units in which the tool operates are CGS so, the units for E are statvolt/cm (or dyne/statcoulomb)

Regards, Baudilio