Precision Lifetime Measurements of Excited States in $^{38}$Si
ORAL
Abstract
The nuclear shell structure significantly evolves in the neutron-rich region at the traditional magic numbers N=20 and 28, resulting in rapid shape transitions as predicted by shell model calculations. The energy ratios between the first 2$^{+}$ and 4$^{+}$ states in the even-even Si isotopes from N=20 to 28 suggest a variety of collectivity evolving from vibrational, to possible triaxial, to rotational modes. The systematic behavior of the level schemes along the Si isotopic chain suggests $^{38}$Si as the turning point in this transition. The lifetime measurement of $^{38}$Si was performed at the National Superconducting Cyclotron Laboratory based on the Recoil-Distance Method using the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA). The data are used to extract the B(E2) ratio which provides a useful measurement to assess the nature of collective modes.
*This material is based upon work supported by the Department of Energy National Nuclear Security Administration through the Nuclear Science and Security Consortium under Award Number DE-NA0003180
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