  Recent evidence for direct CP violation in non-leptonic charm decays cannot
be easily accommodated within the Standard Model (SM). On the other hand, it
fits well in new physics models generating CP violating Delta C=1
chromomagnetic dipole operators. We show that in these frameworks sizable
direct CP asymmetries in radiative D to P+ P- gamma decays (P=pi,K), with M_PP
close to the rho or the phi peak, can be expected. Enhanced matrix elements of
the electromagnetic dipole operators can partly compensate the long distance
dominance in these decays, leading to CP asymmetries of the order of several
percent. If observed at this level, these would provide a clean signal of
physics beyond the SM and of new dynamics associated to dipole operators. We
briefly comment on related CP violating observables accessible via time
dependent D(Dbar) to P+ P- gamma studies and angular decay product
distributions in rare semileptonic D decays.

High Energy Physics - Phenomenology;High Energy Physics - Experiment