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An Electrostatic Sector Field

An electrostatic sector field is defined by the command: 7 E(LECTROSTATIC) S(ECTOR-FIELD) <radius of deflection $\rho_{E0}$ in meter> <angle of deflection $\phi_0$ in degrees> <half electrode gap G0 in meter> <nE1> <nE2> <nE3> ; [example: E   S   1.0   90   0.03   1 ;] [E   S   1.0   90   0.01   0   0   0 ;]

where the toroidicity of the mid-equipotential surface of the sector field is determined by RE (see Fig. 4.17 in Ref. 7) with

\begin{displaymath}
\frac{\rho_{E0}}{R_E} = n_{E1} + n_{E2}
\left(
\frac{x}{\rho...
...\frac{n_{E3}}{2}
\left(
\frac{x}{\rho_{E0}}
\right)^2 + \ldots
\end{displaymath}

For first- and second-order calculations nE1 is defined for -2<nE1<2. For third-order calculations nE1 is defined only for 0<nE1<2. Special cases are:

KPII
1999-10-20