  Using data obtained through simultaneous measurements of (p,p') spin-transfer
observables and (p,p'gamma) coincident spin observables, we have made a
model-independent determination of the complete scattering amplitude for the
15.11 MeV, 1+, T=1 state in 12C at an incident proton energy of 200 MeV, for
four center of mass proton scattering angles ranging from 5.5 to 16.5 degrees.
At each angle, 16 different observables were determined, whereas only 11
independent quantities are required to specify the transition amplitude for
this state. It had been shown previously that the set of observables measured
span the allowed space; hence the system is overdetermined, which allowed us to
extract, in a model-independent fashion, each of the individual spin-operator
amplitudes that characterize the reaction. Additional insight into the physical
mechanisms that drive this transition is obtained by mapping out the
momentum-transfer dependence of these amplitudes. We also compare the
magnitudes and phases determined for each of the spin-operator amplitudes to
the predictions of calculations performed in both relativistic and
nonrelativistic frameworks, and discuss the physics content of these
comparisons.
