학술논문
Evidence for enhanced neutron-proton correlations from the level structure of the $N=Z+1$ nucleus $^{87}_{43}$Tc$^{\ }_{44}$
Document Type
Working Paper
Author
Liu, X.; Cederwall, B.; Qi, C.; Wyss, R. A.; Aktas, Ö.; Ertoprak, A.; Zhang, W.; Clément, E.; de France, G.; Ralet, D.; Gadea, A.; Goasduff, A.; Jaworski, G.; Kuti, I.; Nyakó, B. M.; Nyberg, J.; Palacz, M.; Wadsworth, R.; Valiente-Dobón, J. J.; Al-Azri, H.; Nyberg, A. Ataç; Bäck, T.; de Angelis, G.; Doncel, M.; Dudouet, J.; Gottardo, A.; Jurado, M.; Ljungvall, J.; Mengoni, D.; Napoli, D. R.; Petrache, C. M.; Sohler, D.; Timár, J.; Barrientos, D.; Bednarczyk, P.; Benzoni, G.; Birkenbach, B.; Boston, A. J.; Boston, H. C.; Burrows, I.; Charles, L.; Ciemala, M.; Crespi, F. C. L.; Cullen, D. M.; Désesquelles, P.; Domingo-Pardo, C.; Eberth, J.; Erduran, N.; Ertürk, S.; González, V.; Goupil, J.; Hess, H.; Huyuk, T.; Jungclaus, A.; Korten, W.; Lemasson, A.; Leoni, S.; Maj, A.; Menegazzo, R.; Million, B.; Perez-Vidal, R. M.; Podolyàk, Zs.; Pullia, A.; Recchia, F.; Reiter, P.; Saillant, F.; Salsac, M. D.; Sanchis, E.; Simpson, J.; Stezowski, O.; Theisen, C.; Zielińska, M.
Source
Subject
Language
Abstract
The low-lying excited states in the neutron-deficient $N=Z+1$ nucleus $^{87}_{43}$Tc$^{\ }_{44}$ have been studied via the fusion-evaporation reaction $^{54}$Fe($^{36}$Ar, $2n1p$)$^{87}$Tc at the Grand Acc\'el\'erateur National d'Ions Lourds (GANIL), France. The AGATA spectrometer was used in conjunction with the auxiliary NEDA, Neutron Wall, and DIAMANT detector arrays to measure coincident prompt $\gamma$-rays, neutrons, and charged particles emitted in the reaction. A level scheme of $^{87}$Tc from the (9/2$^{+}_{g.s.}$) state to the (33/2$^{+}_{1}$) state was established based on 6 mutually coincident $\gamma$-ray transitions. The constructed level structure exhibits a rotational behavior with a sharp backbending at $\hbar\omega\approx 0.50$ MeV. A decrease in alignment frequency and increase in alignment sharpness in the odd-mass isotonic chains around $N=44$ is proposed as an effect of the enhanced isoscalar neutron-proton interactions in odd-mass nuclei when approaching the $N=Z$ line.