Excitation spectra and electromagnetic transitions between low-lying nonrotational states of odd-proton nuclei with Z=97−109

Background: Calculations of the structure of the low-lying states of nuclei with $Z=97--109$ play an important role in understanding the properties of nuclei belonging to the new region of the nuclide chart, which is available now for experimental study.Purpose: To calculate quasiparticle-phonon structure and the reduced $\ensuremath{\gamma}$-transition probabilities for the excited states with excitation energies below 1 MeV for odd-proton nuclei with $Z=97\ensuremath{-}109$.Methods: The quasiparticle-phonon model, which takes into account the quasiparticle-phonon interaction of different multipolarities, is used as a basis for the calculations.Results: The quasiparticle-phonon structure and the $\ensuremath{\gamma}$-reduced transition probabilities of odd-proton nuclei $^{263,265,267,269}\mathrm{Mt}$, $^{259,261,263,265}\mathrm{Bh}$, $^{255,257,259,261,263}\mathrm{Db}$, $^{251,253,255,257,259,261}\mathrm{Lr}$, $^{249,251,253,255}\mathrm{Md}$, $^{245,247,249,251}\mathrm{Es}$, and $^{243,245,247}\mathrm{Bk}$ are calculated. The $\ensuremath{\alpha}$-decay chains starting from $^{263,265,267,269}\mathrm{Mt}$ are analyzed.Conclusion: The structure of the nuclear states with excitation energies below 1 MeV in the considered nuclei is mainly exhausted by the one-quasiparticle component. However, in some isotopes the quasiparticle-phonon admixtures plays an important role to destroy the smooth isotopic dependence of energy of the states. The nuclei in the $\ensuremath{\alpha}$-decay chains starting from $^{263,265,267,269}\mathrm{Mt}$ have up to two $\ensuremath{\alpha}$-decay lines. The number of $\ensuremath{\alpha}$-decay lines could be different in the $\ensuremath{\alpha}$-decay chain and in the direct production of the nucleus.