Eur. Phys. J. A (2009) 40: 35-43
https://doi.org/10.1140/epja/i2008-10727-x

Regular Article - Experimental Physics

Role of cross-shell excitations in the reaction ⁵⁴Fe(, p)⁵⁵Fe

¹ Physik Department, Technische Universität München, D-85748, Garching, Germany
² Institut für Angewandte Physik und Messtechnik, Universität der Bundeswehr München, D-85577, Neubiberg, Germany
³ Horia Hulubei National Institute of Physics and Nuclear Engineering (IFIN-HH), R-77125, Bucharest, Romania
⁴ Department für Physik, Ludwig Maximilians Universität München, D-85748, Garching, Germany
⁵ Gesellschaft für Schwerionenforschung, D-64291, Darmstadt, Germany
⁶ Department of Physics, University of Arizona, 85721, Tucson, AZ, USA

^* e-mail: ekruecken@ph.tum.de

Received: 9 October 2008
Revised: 31 December 2008
Accepted: 22 January 2009
Published online: 20 February 2009

Abstract

The reaction ⁵⁴Fe(, p)⁵⁵Fe was studied at the Munich Q3D spectrograph with a 14MeV polarized deuteron beam. Excitation energies, angular distributions and analyzing powers were measured for 39 states up to 4.5MeV excitation energy. Spin and parity assignments were made and spectroscopic factors deduced by comparison to DWBA calculations. The results were compared to predictions by large-scale shell model calculations in the full pf -shell and it was found that reasonable agreement for energies and spectroscopic factors below 2.5MeV could only be obtained if up to 6 particles were allowed to be excited from the f _7/2 orbital into p _3/2 , f _5/2 , and p _1/2 orbitals across the N = 28 gap. For levels above 2.5MeV the experimental strength distribution was found to be significantly more fragmented than predicted by the shell model calculations.