1. Quadrupole collectivity in Ca 42 from low-energy Coulomb excitation with AGATA
- Author
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Hadyńska-Klk, K., Napiorkowski, P. J., Zielińska, M., Srebrny, J, Maj, A., Azaiez, F., Valiente-Dobón, J. J., Kicińska-Habior, M, Nowacki, F, Naïdja, H, Bounthong, B, Rodríguez, T R, de Angelis, G, Abraham, W T, Anil Kumar, G., Bazzacco, D., Bellato, M., Bortolato, D., Bednarczyk, P, Benzoni, G., Berti, L., Birkenbach, B., Bruyneel, B., Brambilla, S., Camera, F., Chavas, J., Cederwall, B, Charles, Lucie, Ciemała, M, Cocconi, P., Coleman-Smith, P J, Colombo, A., Corsi, A., Crespi, F. C. L., Cullen, D. M., Czermak, A., Désesquelles, P, Doherty, D. T., Dulny, B, Eberth, J, Farnea, E, Fornal, B., Franchoo, S, Gadea, A., Giaz, A., Gottardo, A., Grave, X., Grebosz, J., Görgen, A., Gulmini, M., Habermann, T., Hess, H., Isocrate, R, Iwanicki, J., Jaworski, G., Judson, D S, Jungclaus, A., Karkour, N., Kmiecik, M., Karpiński, D, Kisieliński, M, Kondratyev, N., Korichi, A., Komorowska, M., Kowalczyk, M, Korten, W, Krzysiek, M., Lehaut, G., Leoni, S., Ljungvall, J., Lopez-Martens, A., Lunardi, S., Maron, G., Mazurek, K., Menegazzo, R., Mengoni, D., Merchán, E., Meczyński, W., Michelagnoli, C., Million, B., Myalski, S., Napoli, D. R., Niikura, M., Obertelli, A., Özmen, S.F., Palacz, M., Próchniak, L, Pullia, A., Quintana, B., Rampazzo, G., Recchia, F., Redon, N, Reiter, P, Rosso, D., Rusek, K, Sahin, E., Salsac, M. -D., Söderström, P.-A., Stefan, I., Stézowski, O., Styczeń, J., Theisen, Ch., Toniolo, N., Ur, C. A., Wadsworth, R., Wasilewska, B., Wiens, A., Wood, J. L., Wrzosek-Lipska, K, Ziebliński, M., Helmholtz Centre for Heavy Ion Research, European Commission, Federal Ministry of Education and Research (Germany), Polish Academy of Sciences, Ministerio de Economía y Competitividad (España), Research Council of Norway, and Generalitat Valenciana
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Nuclear and High Energy Physics - Abstract
20 pags., 12 figs., 14 tabs., A Coulomb-excitation experiment to study electromagnetic properties of Ca42 was performed using a 170-MeV calcium beam from the TANDEM XPU facility at INFN Laboratori Nazionali di Legnaro. γ rays from excited states in Ca42 were measured with the AGATA spectrometer. The magnitudes and relative signs of ten E2 matrix elements coupling six low-lying states in Ca42, including the diagonal E2 matrix elements of 21+ and 22+ states, were determined using the least-squares code gosia. The obtained set of reduced E2 matrix elements was analyzed using the quadrupole sum rule method and yielded overall quadrupole deformation for 01,2+ and 21,2+ states, as well as triaxiality for 01,2+ states, establishing the coexistence of a weakly deformed ground-state band and highly deformed slightly triaxial sideband in Ca42. The experimental results were compared with the state-of-the-art large-scale shell-model and beyond-mean-field calculations, which reproduce well the general picture of shape coexistence in Ca42., K.H.-K. acknowledges support from the Research Council of Norway under Grant No. 213442. T.R.R. acknowledges computing time at GSI-Darmstadt and support from Spanish MINECO under Programa Ramon y Cajal 11420 and FIS-2014-53434-P (T.R.R.). We also acknowledge the support by Generalitat Valenciana, Spain, under Grant No. PROMETEOII/2014/019 and by the FEDER funds of the European Commission (A. Gadea), Spanish Ministerio de Economía y Competitividad under contract FPA2014-57196-C5 (A. Jungclaus, A Gadea), German Bundesministerium für Bildung und Forschung (BMBF) under Contract No. 05P12PKFNE TP4 (B. Birkenbach), the Polish National Science Centre under Projects No. 2011/03/B/ST2/01894, No. DEC-2013/10/M/ST2/00427, No. 2013/08/M/ST2/00591, No. UMO-2014/14/M/ST2/00738 (COPIN-INFN Collaboration), No. 2015/17/B/ST2/01534, No. 2016/22/M/ST200269, the UK STFC under Grants No. ST/J000124/1 and No. ST/L005735/1. The EAGLE Collaboration thanks the European Gamma-Ray Spectroscopy Pool (GAMMAPOOL) for the loan of Ge detectors.
- Published
- 2018