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تسجيل مستخدم جديدIdentification of mixed-symmetry states in an odd-mass nearly-spherical nucleus
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The low-spin structure of 93Nb has been studied using the (n,n gamma) reaction at neutron energies ranging from 1.5 to 3.0 MeV and the 94Zr(p,2n gamma)93Nb reaction at bombarding energies from 11.5 to 19 MeV. States at 1779.7 and 1840.6 keV, respectively, are proposed as mixed-symmetry states associated with the coupling of a proton hole in the p_1/2 orbit to the 2+_1,ms state in 94Mo. These assignments are derived from the observed M1 and E2 transition strengths to the symmetric one-phonon states, energy systematics, spins and parities, and comparison with shell model calculations.
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A comprehensive decay scheme of $^{93}$Nb below 2 MeV has been constructed from information obtained with the $^{93}$Nb(n,n$^prime$$gamma$) and $^{94}$Zr(p,2n$gamma$$gamma$)$^{93}$Nb reactions. Branching ratios, lifetimes, transition multipolarities
and spin assignments have been determined. From $M1$ and $E2$ strengths, fermionic-bosonic excitations of isoscalar and isovector character have been identified from the weak coupling $pi1g_{9/2}$$otimes$$^{92}_{40}$Zr and $pi2p_{1/2}^{-1}$$otimes$$^{94}_{42}$Mo configurations. A microscopic interpretation of such excitations is attained from shell-model calculations using low-momentum effective interactions.
The structure of the nucleus 25F was investigated through in-beam {gamma}-ray spectroscopy of the fragmentation of 26Ne and 27,28Na ion beams. Based on the particle-{gamma} and particle-{gamma}{gamma} coincidence data, a level scheme was constructed
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