Reinvestigation of the level structures of the N=49 isotones Zr89 and Mo<…

Excited states of $^{89}\mathrm{Zr}$ and $^{91}\mathrm{Mo}$ have been investigated using the fusion reaction $^{6}\mathrm{Li}+^{89}\mathrm{Y}$ at beam energy of 34 MeV. Based on new experimental data, about 16 (13) new transitions have been added to the level scheme of $^{89}\mathrm{Zr}$ ($^{91}\mathrm{Mo}$). The level structures are investigated in the framework of the spherical-basis shell model using the effective interactions JUN45 and GWBXG. Reasonable agreement is obtained between the experimental results and the calculations. The calculated results indicate the newly proposed states are characterized by proton excitations from the $1{f}_{5/2}, 2{p}_{3/2}, 2{p}_{1/2}$ orbits to the high-$j 1{g}_{9/2}$ orbit. The systematic features of low lying states in the $N=49$ isotones are discussed.