Hunting η-bound nuclei
- Received Date: 2010-03-04
- Accepted Date: 1900-01-01
- Available Online: 2010-09-05
Abstract:
The η meson can be bound to atomic nuclei. Experimental search is discussed in the form of final state interaction for the reactions dp→3Heη and dd→4Heη. For the latter case tensor polarized deuterons were used in order to extract the s-wave strength. For both reactions complex scattering lengths are deduced: a3Heη=[±(10.7±0.8-0.5 +0.1)+i.(1.5±2.6-0.9+1.0)] fm and a4Heη=[±(3.1±0.5)+i.(0±0.5)] fm. In a two-nucleon transfer reaction under quasi-free conditions, p27Al→^3HeX, was investigated. The system X can be the bound 25Mg⊙η at rest. When a possible decay of an intermediate N*(1535) is required, a highly significant bump shows up in the missing mass spectrum. The data give for a bound state a binding energy of 13.3±1.6 MeV and a width of σ=4.4±1.3 MeV.