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A new method of extracting the g-ray intensities necessary to perform lifetime measurements using the differential decay curve method (DDCM) is presented in this work, the unresolved Doppler-shifted components method (UDCM). The UDCM allows for a DDCM analysis to be performed using a g-ray transition for which the fully Doppler-shifted and degraded components are unresolvable in energy and so are detected as a single peak. This technique was used to measure the known lifetime of the yrast 2+1 state in 50Mn with a depopulating transition that does not have resolvable fully Doppler-shifted and degraded components. The lifetime measured through applying the UDCM was consistent with the standard DDCM measurement of the 2+1 state. Use of the UDCM allows for DDCM lifetime measurements to be made using transitions of smaller g-ray energies, smaller recoil velocities and, in some cases, with a smaller uncertainty. In contrast to a standard DDCM analysis, a UDCM analysis is also independent of the widths of the fully Doppler-shifted and degraded components and as a result they do not need to be determined.

Lifetimes of the T = 1 isobaric analog Ip = 2+ states in 50Mn and 50Cr were measured simultaneously by employing the recoil distance Doppler-shift (RDDS) technique. The states were populated in a fusion-evaporation reaction with a ¹²C beam on a 40Ca target. An analysis of the data and the calculations from the present work, together with the available B(E2 : 2+ RT 0+) data of the isobaric analog states in 50Fe and 50Cr, were used to study isospin symmetry in the three A = 50 isobaric nuclei. Shell-model calculations reproduce the magnitudes as well as the increasing trend of the B(E2) data with increasing Z. To draw a firm conclusion on the level of isospin mixing in the triplet, a new precision measurement of the 2+ RT 0+ transition rate in 50Fe will be required.