A Study of e+e- -> H0A0 Production and the Constraint on Dark Matter Density

This paper reports the results of a study of the e+e- -> H0A0 process at 1 TeV performed on fully simulated and reconstructed events. The estimated accuracies on the heavy Higgs boson masses, widths and decay branching fractions are discussed in relation to the study of Supersymmetric Dark Matter.