1. Low collectivity of the first 2⁺ states of ²¹²,²¹⁰Po
- Author
-
Kocheva, D., Rainovski, G., Jolie, J., Pietralla, N., Blazhev, A., Astier, A., Altenkirch, R., Bast, M., Beckers, M., Ansari, S., Braunroth, Th., Cappellazzo, M., Cortés, M.L., Dewald, A., Diel, F., Djongolov, M., Fransen, C., Gladnishki, K., Goldkuhle, A., Hennig, A., Karayonchev, V., Keatings, J.M., Kluge, E., Kröll, Th., Litzinger, J., Moschner, K., Müller-Gatermann, C., Petkov, P., Rudigier, M., Scheck, M., Spagnoletti, P., Scholz, Ph., Schmidt, T., Spieker, M., Stahl, C., Stegmann, R., Stolz, A., Vogt, A., Stoyanova, M., Thöle, P., Warr, N., Werner, V., Witt, W., Wölk, D., Zamora, J.C., Zell, K.O., Van Isacker, P., Ponomarev, V. Yu., Kocheva, D., Rainovski, G., Jolie, J., Pietralla, N., Blazhev, A., Astier, A., Altenkirch, R., Bast, M., Beckers, M., Ansari, S., Braunroth, Th., Cappellazzo, M., Cortés, M.L., Dewald, A., Diel, F., Djongolov, M., Fransen, C., Gladnishki, K., Goldkuhle, A., Hennig, A., Karayonchev, V., Keatings, J.M., Kluge, E., Kröll, Th., Litzinger, J., Moschner, K., Müller-Gatermann, C., Petkov, P., Rudigier, M., Scheck, M., Spagnoletti, P., Scholz, Ph., Schmidt, T., Spieker, M., Stahl, C., Stegmann, R., Stolz, A., Vogt, A., Stoyanova, M., Thöle, P., Warr, N., Werner, V., Witt, W., Wölk, D., Zamora, J.C., Zell, K.O., Van Isacker, P., and Ponomarev, V. Yu.
- Abstract
The lifetimes of the first 2⁺ excited states of ²¹²,²¹⁰Po were measured in two transfer reactions ²⁰⁸Pb(¹²C,⁸Be)²¹²Po and ²⁰⁸Pb(¹²C,¹⁰Be)²¹⁰Po by the Recoil Distance Doppler Shift (RDDS) method and by the Doppler Shift Attenuation method (DSAM), respectively. The derived absolute B(E2) values of 2.6(3) W.u. for ²¹²Po and 1.83(28) W.u. for ²¹⁰Po indicate low collectivity. It is shown that the properties of the yrast 2₁⁺, 4₁⁺, 6₁⁺ and 8₁⁺ states in both nuclei cannot be described consistently in the framework of nuclear shell models. It is also demonstrated in the case of ²¹⁰Po that Quasi-particle Phonon Model (QPM) calculations cannot overcome this problem thus indicating the existence of a peculiarity which is neglected in both theoretical approaches.
- Published
- 2024