  Isochronous mass spectrometry was applied to measure isomeric yield ratios of
fragmentation reaction products. This approach is complementary to conventional
gamma-ray spectroscopy in particular for measuring yield ratios for long-lived
isomeric states. Isomeric yield ratios for the high-spin I = 19/2 states in the
mirror nuclei 53Fe and 53Co are measured to study angular momentum population
following the projectile fragmentation of 78Kr at energies of 480A MeV on a
beryllium target. The 19/2 state isomeric ratios of 53Fe produced from
different projectiles in the literature have also been extracted as a function
of mass number difference between projectile and fragment (mass loss). The
results are compared to ABRABLA07 model calculations. The isomeric ratios of
53Fe produced using different projectiles suggest that the theory
underestimates not only the previously reported dependence on the spin but also
the dependence on the mass loss.
