  Theoretical models often differ significantly from measured data in their
predictions of the magnitude of nuclear reactions that produce radionuclides
for medical, research, and national security applications. In this paper, we
compare a priori predictions from several state-of-the-art reaction modeling
packages (CoH, EMPIRE, TALYS, and ALICE) to cross sections measured using the
stacked-target activation method. The experiment was performed using the LBNL
88-Inch Cyclotron with beams of 25 and 55 MeV protons on a stack of iron,
copper, and titanium foils. 34 excitation functions were measured for 4 < Ep <
55 MeV, including the first measurement of the independent cross sections for
natFe(p,x) 49,51Cr, 51,52m,52g,56Mn, and 58m,58gCo. All of the models failed to
reproduce the isomer-to-ground state ratio for reaction channels at compound
and pre-compound energies, suggesting issues in modeling the deposition or
distribution of angular momentum in these residual nuclei.
