Disentangling violations of CPT from other new-physics effects - art. no. 056003

We analyze the prospects for observing CPT violation using neutral-meson P- 0-<(P-0)over bar> systems. Before one can claim a measurement of CPT violat ion, one must be able to rule out the possibility that its result is due to simpler new-physics effects. In particular, one must be able to separate t he CPT-violating quantities from parameters violating the Delta P=Delta Q r ule of semileptonic decays, and from new-physics contributions to the produ ction mechanism of the neutral mesons. One can isolate CPT violation using the semileptonic decays of single, tagged neutral mesons; unfortunately, th is situation cannot be implemented at the Y(4S). For P-0<(P-0)over bar> pai rs produced in a correlated parity-odd state we show that, by combining the di-lepton with the single-lepton decays, it is in principle possible to ex tract unambiguously one CPT-violating parameter. Finally, we develop the fo rmalism necessary for describing new-physics effects in the production mech anism; this includes both cascade decays and violations of the rule of asso ciated production. [S0556-2821(99)04617-2].