What is the formula of electric field in the example DriftTube?

[newconcept1979]

if the formula is:

then what are the values of C and ε0?
C: the capacitance of unit length;
ε0: the dielectric constant of the gas.
if not, What is the formula of electric field?

[mdessole]

Hello @newconcept1979,

your question looks more theoretical rather than software related. In the Garfield++ user guide, there is an example of drift tube that may help you.

Cheers,
Monica

[hschindl]

Hi,
for a concentric wire (radius a) at a potential V inside a tube with radius b, the electric field is given by
E(r) = (V / ln(a/b)) / r

[newconcept1979]

@hschindl , thanks,