Single and pair production of MSSM Higgs bosons as a probe of scalar-pseudoscalar mixing at e+e- colliders

We study the associated production of the $A^0$ neutral CP–odd Higgs boson with a neutral gauge boson $Z$ as well as single production of $A^0$ via $e^{+}{e}^{-}\to {\nu }_e{\bar{\nu }}_e{A}^0$ at the one loop level in the Minimal Supersymmetric Standard Model (MSSM). We show that the MSSM cross–section may be enhanced by light SUSY particles. Then we study the production processes $e^{+}{e}^{-}\to H_i^{0}Z$, $H_i^0{\nu }_e{\bar{\nu }}_e$ and $H_i^0{H}_j^0$ in the context of the MSSM with scalar-pseudoscalar mixing. In a given channel we show that the cross–section for all i (=1,2,3) can be above 0.1 fb provided $M_{H_{2,3}}\la 300$ GeV. This should be detectable at a Next Linear Collider and would provide evidence for scalar–pseudoscalar mixing.