Drift velocity and deflection in non-perpendicular electric and magnetic fields

Accurate tracking in inhomogeneous and arbitrarily oriented magnetic fields requires the velocity and direction of the drifting ionization to be known to high precision. A semi-empirical method of calculating drift velocities and magnetic deflection angles is presented for non-perpendicular electric and magnetic fields. Data obtained using a drift chamber rotated in a B-field verify the calculation. The model is used to restore accuracy in the L3 forward/backward muon detector where non-orthogonal and inhomogeneous electric and magnetic fields are present.