CP VIOLATION IN SINGLE TOP-QUARK PRODUCTION AND DECAY VIA P(P)OVER-BAR-]T(B)OVER-BAR-]W(+)B(B)OVER-BAR+X WITHIN THE MSSM - A POSSIBLE APPLICATION FOR MEASURING ARG(A(T)) AT HADRON COLLIDERS(X)

CP-nonconserving effects in the reaction p (p) over bar --> t (b) over bar + X --> W(+)b (b) over bar + X, driven by the supersymmetric CP-o dd phase of the top squark trilinear soft breaking term arg(A(t)), are studied. We discuss the CP-nonconserving effects in both production a nd the associated decay amplitudes of the top quark. We find that, wit hin a plausible low energy scenario of the MSSM and keeping the neutro n electric dipole moment below its current limit, a CP-violating cross -section asymmetry as large as 2 - 3% can arise if some of the paramet ers lie in a favorable range. A partial rate asymmetry originating onl y in the top quark decay t --> W(+)b is found to be, in general, below the 0.1% level which is somewhat smaller than previous claims. For a low tan beta of order one the decay asymmetry can reach at the most si milar to 0.3%. This (few) percent level overall CP-violating signal in p (p) over bar --> t (b) over bar + X --> W(+)b (b) over bar + X migh t be within the reach of the future 2(4) TeV p (p) over bar Fermilab T evatron collider that may be able to produce similar to 10000 (similar to 30000) such t (b) over bar events with an integrated luminosity of 30 fb(-1). In particular, it may be used to place an upper bound on a rg(A(t)) if indeed arg(mu) --> 0, as implied from the present experime ntal limit on the neutron electric dipole moment. The partial rate asy mmetry in the top quark decay (similar to few X 10(-3)) may also be wi thin the reach of the CERN LHC with similar to 10(7) pairs of t (t) ov er bar produced, provided detector systematics are sufficiently small. We also show that if the GUT scale universality of the soft breaking trilinear A terms is relaxed, then the phases associated with arg(A(u) ) and arg(A(d)) can take values up to similar to few X 10(-1) even wit h squarks and gluino masses of several hundred GeV's without contradic ting the experimental limit on the neutron electric dipole moment.