Shunt impedance

Longitudinal shunt impedance
To produce longitudinal Coulomb forces which add up to the (longitudinal) acceleration voltage, an eigenmode of the resonator has to be excited, leading to power dissipation \scriptstyle P. The definition of the longitudinal effective shunt impedance. Because the transverse deflection can be described with polar coordinates, one may define a deflection or polarization angle using the transverse acceleration voltage components. Polar coordinates are used because it is possible to add up voltage components like vectors, but not shunt impedances.