Eur. Phys. J. A (2003) 20: 153-156
https://doi.org/10.1140/epja/i2002-10342-y

Selection of cold transfer and enhanced neutron-pair transfer in the ²⁰⁶ Pb + ¹¹⁸ Sn reaction

¹ Hahn-Meitner-Institut Berlin, Glienicker Strasse 100, 14109, Berlin, Germany
² Fachbereich Physik, Freie Universitaet Berlin, Berlin, Germany
³ Gesellschaft für Schwerionenforschung Darmstadt, Planckstrasse 1, 64291, Darmstadt, Germany
⁴ INFN, Sezione di Padova, Via Marzolo 8, 35131, Padova, Italy

^* e-mail: oertzen@hmi.de

Abstract

The neutron transfer in a very heavy asymmetric nuclear system, in ²⁰⁶ Pb + ¹¹⁸ Sn has been measured using particle- coincidence techniques with position-sensitive detectors, 5 EUROBALL-Cluster detectors (EB) and the Heidelberg-Darmstadt NaI-CRYSTAL BALL (CB). The fragments are identified via the known -decays of the lowest excited states using the high resolution of EB. Using the unique feature of the set-up with the CB, transfer to well-defined final channels with known quantum numbers is selected using the high-efficiency multiplicity filter of the CB with no second -ray, i.e. without feeding. The enhancement in the two-neutron transfer is deduced, for population of the low-lying super-fluid 2 ⁺ states in ¹²⁰ Sn and ¹¹⁶ Sn, while the 2n-transition remains in the ground state for the recoiling ^20X Pb-nuclei. Large enhancements up to EF are observed. This is the first observation of neutron pair-transfer enhancement for a heavy nuclear binary system with superfluid properties with experimentally separated levels.