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.
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