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تسجيل مستخدم جديدIdentification of a long lived $beta$ decaying isomer in $^{150}$Pm
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The decay of odd-odd $^{150}$Pm has been studied by populating the nucleus with the $^{150}$Nd(p,n)$^{150}$Pm reaction at E$_{beam}$ = 8.0 MeV using 97$%$ enriched $^{150}$Nd target. The presence of an isomeric state with $beta$ decay half life of 2.2(1) h could be identified in $^{150}$Pm by following the half lives of the observed $gamma$ transitions. The decay of the isomer to the excited levels of $^{150}$Sm has been confirmed by observing the $gamma - gamma$ coincidence with the VENUS array of six Compton suppressed Clover HPGe detectors. The $beta$ decay end-point energies corresponding to the decay from the $^{150g}$Pm and $^{150m}$Pm have been measured using a $beta-gamma$ coincidence setup of two thin window Planar HPGe detectors and four Clover HPGe detectors of the VENUS array. The systematics of the similar isomeric states in neighboring nuclei has been studied to understand the underlying structure of these states. Shell model calculation has been performed by using OXBASH code which indicates the presence of a 5$^-$ isomeric state at very low excitation in the nucleus. The calculation also suggests hindered electromagnetic decay of this isomer and supports the possibility of its $beta$ decay to the excited levels of $^{150}$Sm.
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