Eur. Phys. J. A (2004) 19: 187-201
https://doi.org/10.1140/epja/i2003-10124-1

Broad states beyond the neutron drip line

Examples of ⁵ H and ⁴ n

¹ GSI, Planckstrasse 1, D-64291, Darmstadt, Germany
² Russian Research Center “The Kurchatov Institute”, 123182, Moscow, Russia
³ Department of Physics, University of Surrey, GU2 7XH, Guildford, UK
⁴ Department of Physics, Chalmers University of Technology and Göteborg University, S-41296, Göteborg, Sweden

^* e-mail: L.Grigorenko@gsi.de

Abstract

Theoretical studies of broad states in the few-body systems beyond the neutron drip line have been performed. We introduce a theoretical model which allows to incorporate the initial structure of colliding nuclei, reaction mechanism, few-body effects and final-state interactions in studies of broad unbound states. The model is directly related to the sudden-removal approximation for high-energy knock-out or break-up reactions. We apply this model to qualitative studies of some general properties of broad few-body states including correlations for emitted fragments. The theoretical ideas are illustrated mainly using the example of ⁵H. The prospect for observation of broad continuum structures corresponding to the tetraneutron ⁴n is also discussed.