1. Identification of high-spin proton configurations in Ba-136 and Ba-137
- Author
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Kaya, L., Vogt, A., Reiter, P., Mueller-Gatermann, C., Gargano, A., Coraggio, L., Itaco, N., Blazhev, A., Arnswald, K., Bazzacco, D., Birkenbach, B., Bracco, A., Bruyneel, B., Corradi, L., Crespi, F. C. L., de Angelis, G., Droste, M., Eberth, J., Farnea, E., Fioretto, E., Fransen, C., Gadea, A., Giaz, A., Gorgen, A., Gottardo, A., Hadynska-Klek, K., Hess, H., Hetzenegger, R., Hirsch, R., John, P. R., Jolie, J., Jungclaus, A., Korten, W., Leoni, S., Lewandowski, L., Lunardi, S., Menegazzo, R., Mengoni, D., Michelagnoli, C., Mijatovic, T., Montagnoli, G., Montanari, D., Napoli, D., Podolyak, Zs, Pollarolo, G., Recchia, F., Rosiak, D., Saed-Samii, N., Sahin, E., Siciliano, M., Scarlassara, F., Seidlitz, M., Soderstrom, P-A, Stefanini, A. M., Stezowski, O., Szilner, S., Szpak, B., Ur, C., Valiente-Dobon, J. J., Weinert, M., Wolf, K., Zell, K. O., Kaya, L., Vogt, A., Reiter, P., Mueller-Gatermann, C., Gargano, A., Coraggio, L., Itaco, N., Blazhev, A., Arnswald, K., Bazzacco, D., Birkenbach, B., Bracco, A., Bruyneel, B., Corradi, L., Crespi, F. C. L., de Angelis, G., Droste, M., Eberth, J., Farnea, E., Fioretto, E., Fransen, C., Gadea, A., Giaz, A., Gorgen, A., Gottardo, A., Hadynska-Klek, K., Hess, H., Hetzenegger, R., Hirsch, R., John, P. R., Jolie, J., Jungclaus, A., Korten, W., Leoni, S., Lewandowski, L., Lunardi, S., Menegazzo, R., Mengoni, D., Michelagnoli, C., Mijatovic, T., Montagnoli, G., Montanari, D., Napoli, D., Podolyak, Zs, Pollarolo, G., Recchia, F., Rosiak, D., Saed-Samii, N., Sahin, E., Siciliano, M., Scarlassara, F., Seidlitz, M., Soderstrom, P-A, Stefanini, A. M., Stezowski, O., Szilner, S., Szpak, B., Ur, C., Valiente-Dobon, J. J., Weinert, M., Wolf, K., and Zell, K. O.
- Abstract
The high-spin structures of Ba-136 and Ba-137 are investigated after multinucleon-transfer (MNT) and fusion-evaporation reactions. Ba-136 is populated in a Xe-136 + U-238 MNT reaction employing the high-resolution Advanced GAmma Tracking Array (AGATA) coupled to the magnetic spectrometer PRISMA at the Laboratori Nazionali di Legnaro, Italy, and in two Be-9 + Te-130 fusion-evaporation reactions using the High-efficiency Observatory for gamma-Ray Unique Spectroscopy (HORUS) at the FN tandem accelerator of the University of Cologne, Germany. Furthermore, both isotopes are populated in an elusive reaction channel in the B-11 + Te-130 fusion-evaporation reaction utilizing the HORUS gamma-ray array. The level scheme above the J(pi) = 10(+) isomer in Ba-136 is revised and extended up to an excitation energy of approximately 5.5 MeV. From the results of angular-correlation measurements, the E-x = 3707- and E-x = 4920-keV states are identified as the bandheads of positive- and negative-parity cascades. While the high-spin regimes of both Te-132 and Xe-134 are characterized by high-energy 12(+) -> 10(+) transitions, the Ba-136 E2 ground-state band is interrupted by negative-parity states only a few hundred keV above the J(pi) = 10(+) isomer. Furthermore, spins are established for several hitherto unassigned high-spin states in Ba-137. The new results close a gap along the high-spin structure of N < 82 Ba isotopes. Experimental results are compared to large-scale shell-model calculations employing the GCN50:82, Realistic SM, PQM130, and SN100PN interactions. The calculations suggest that the bandheads of the positive-parity bands in both isotopes are predominantly of proton character.
- Published
- 2019