Lifetime Measurements and Deformation in $^{79}$Sr

High-spin states in $^{79}$Sr were produced following the $^{54}$Fe ($^{28}$Si, 2pn) fusion-evaporation reaction using a beam energy of 90 MeV at the FSU Tandem-Linac facility, and the resulting de-exciting $\gamma $ rays were detected with the FSU Ge array of 10 Compton-suppressed detectors. The $^{54}$Fe target was thick enough so that all of the synthesized nuclei could stop completely in the target, resulting in Doppler-shifted $\gamma $-ray line shapes that could be analyzed using the Doppler-shift attenuation method. In all, 23 lifetimes were measured in three separate band structures using this method, and then used to infer transition quadrupole moments and quadrupole deformations using the rotational model. The results show good qualitative agreement with the predictions of both cranked Woods-Saxon and projected shell model calculations. The band based on a d$_{5/2}$ single-particle orbit, verified in this study through $\gamma -\gamma $ coincidences, intensity measurements, and directional correlation of oriented nuclei ratios, was found to have the largest average deformation ($\beta _{2,ave}$ = 0.41) among the three bands, in agreement with the calculations.