 | (a) Sum of the spectra gated on the 712.0, 886.5, 1007.4, 845.9 and 956.3 keV lines (red), and the summed background spectrum (black) gated 4 keV above these lines. The background spectrum was normalized to the gated spectrum according to the statistics below 2 MeV. $\gamma$-ray peaks due to contaminant reactions are indicated. The coincidence spectrum in (b) is the difference between the two spectra shown in (a). (c) Level scheme of $^{87}$Tc deduced from the present work. The tentative spin-parity assignments were made based on the systematics as well as shell-model calculations, and the width of the arrows are proportional to the relative intensities of the $\gamma$ rays. The relative intensities: 100(4), 80(3), 65(5), 37(4), 26(3), and 13(3). |
 | Systematics of positive-parity yrast states below 6 MeV in $^{87}$Tc together with the odd-A $N=44$ isotones~\cite{cris1992, gros1991} in comparison with neighboring technetium isotopes $^{89,91,93}$Tc~\cite{rudo1995, ghug1993, rudo1994}. The results for $^{87}$Tc are from the present work. |
 | Kinematic moments of inertia ($J^{(1)}$) as a function of rotational frequency for the positive parity and positive signature bands in the $N=44$ even-even~\cite{pric1983, rudo1996, cede2020} isotones (a), $N=44$ odd-mass isotones (b), and $N=43$ odd-mass~\cite{mar12002, smal1990, john1994} isotones (c). |
 | Left: The experimental level scheme of $^{87}$Tc in comparison with the shell-model calculations in the $p\textsl{g}$ model space based on the slgmt0~\cite{serd1976} interaction (slgmt0* denotes the calculation with the spin-aligned neutron-proton interaction reduced by 200 keV). The cartoon illustrates the coupling between the unpaired neutron with the spin-aligned np pair which is the dominant component of the wave function for the higher-spin states. Right: Kinematic moments of inertia as a function of rotational frequency for the positive parity and positive signature bands in $^{87}$Tc and $^{89}$Tc from the experimental data and theoretical calculations (slgmt0 and slgmt0*). |