New region of deformation in the neutron-rich $\chem{{}^{60}_{24}Cr_{36}}$ and $\chem{{}^{62}_{24}Cr_{38}}$

O. Sorlin; C. Donzaud; F. Nowacki; J.C. Angélique; F. Azaiez; C. Bourgeois; V. Chiste; Z. Dlouhy; S. Grévy; D. Guillemaud-Mueller; F. Ibrahim; K.-L Kratz; M. Lewitowicz; S.M. Lukyanov; J. Mrasek; Yu.-E. Penionzhkevich; F. de Oliveira Santos; B. Pfeiffer; F. Pougheon; A. Poves; M.G. Saint-Laurent; M. Stanoiu

doi:doi:10.1140/epja/i2002-10069-9

2022 Impact factor 2.7

Hadrons and Nuclei

Eur. Phys. J. A 16, 55-61 (2003)
DOI: 10.1140/epja/i2002-10069-9

New region of deformation in the neutron-rich $\chem{{}^{60}_{24}Cr_{36}}$ and $\chem{{}^{62}_{24}Cr_{38}}$

O. Sorlin¹, C. Donzaud¹, F. Nowacki², J.C. Angélique³, F. Azaiez¹, C. Bourgeois¹, V. Chiste¹, Z. Dlouhy⁴, S. Grévy³, D. Guillemaud-Mueller¹, F. Ibrahim¹, K.-L Kratz⁵, M. Lewitowicz⁶, S.M. Lukyanov⁷, J. Mrasek⁴, Yu.-E. Penionzhkevich⁷, F. de Oliveira Santos⁶, B. Pfeiffer⁵, F. Pougheon¹, A. Poves⁸, M.G. Saint-Laurent⁶ and M. Stanoiu⁶

¹ Institut de Physique Nucléaire, IN2P3-CNRS, F-91406 Orsay Cedex, France
² IReS, IN2P3-CNRS, Université Louis Pasteur, BP 28, F-67037 Strasbourg Cedex, France
³ LPC, ISMRA, F-14050 Caen Cedex, France
⁴ Nuclear Physics Institute, AS CR, CZ 25068, Rez, Czech Republic
⁵ Institut für Kernchemie, Universität Mainz, D-55128 Mainz, Germany
⁶ GANIL, B. P. 5027, F-14076 Caen Cedex, France
⁷ FLNR, JINR, 141980 Dubna, Moscow region, Russia
⁸ Departamento de Fisica Teorica, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain

sorlin@ipno.in2p3.fr

(Received: 13 June 2002 / Published online: 17 January 2003)

Abstract
The neutron-rich nuclei $\chem{{}_{23}^{60\tx{-}63}V}$ have been produced at GANIL via interactions of a 61.8 A.MeV $\chem{{}^{76}Ge}$ beam with a $\chem{{}^{58}Ni}$ target. Beta-decay to $\chem{{}_{24}^{60\tx{-}63}Cr}$ has been investigated using combined $\beta$ - and $\gamma$ -ray spectroscopy. Half-lives of the $\chem{{}^{60\tx{-}63}V}$ nuclei have been determined, and the existence of a beta-decay isomer in the $\chem{{}^{60}V}$ nucleus is strongly supported. The observation of low-energy 2⁺ states in $\chem{{}^{60}Cr}$ (646 keV) and $\chem{{}^{62}Cr}$ (446 keV) suggests that these isotopes are strongly deformed with $\beta_2\sim 0.3$ . This is confirmed by shell model calculations which show the dominant influence of the intruder g and d orbitals to obtain low 2⁺ energies in the neutron-rich $\chem{Cr}$ isotopes.

PACS
27.50.+e - $59\leq A\leq 89$ .
23.40.-s - Beta decay; double beta decay; electron and muon capture.
21.60.Cs - Shell model.
21.60.-n - Nuclear-structure models and methods.

© Società Italiana di Fisica, Springer-Verlag 2003