D. Guillemaud-Mueller

Invariant-mass spectroscopy of 10Li and 11Li

Break-up of secondary Li-11 ion beams (280 MeV/nucleon) on C and Pb targets into Li-9 and neutrons is studied experimentally. Cross sections and neutron multiplicity distributions are obtained, characterizing different reaction mechanisms. Invariant-mass spectroscopy for Li-11 and Li-10 is performed. The E1 strength distribution, deduced from electromagnetic excitation of Li-11 up to an excitation energy of 4 MeV comprises similar to 8% of the Thomas-Reiche-Kuhn energy-weighted sumrule strength. Two low-lying resonance-like structures are observed for Li-10 at decay energies of 0.21(5) and 0.62(10) MeV, the former one carrying 26(10)% of the strength and likely to be associated with an s-wave neutron decay. A strong di-neutron correlation in Li-11 can be discarded. Calculations in a quasi-particle RPA approach are compared with the experimental results for Li-10 and Li-11

Observation of forward neutrons from the break-up of the 11Li neutron halo

Abstract The cross-sections and forward angular distributions of fast neutrons have been studied for the reaction (11Li, 9Li) at 29 MeV/u on targets of Be, Ni and Au. The cross-sections are large and arise essentially from peripheral reactions. The angular distributions of the neutrons are very narrow and indicate the existence of a neutron halo with radius of about 12 fm.

Search for 28O and study of neutron-rich nuclei near the N = 20 shell closure

Abstract A search for 28 O with a 78 AMeV beam of the neutron-rich isotope 36 S has been performed for the first time. Evidence for the unbound character of 28 O was obtained. In the same experiment the half-lives of the very neutron-rich isotopes 27,29 F and 30 Ne were measured and those for 28,29 Ne and 30,31 Na reexamined. The results are compared to shell-model predictions and conclusions drawn regarding the extent of the region of deformation around N = 20.

Two-neutron interferometry as a probe of the nuclear halo

The technique of intensity interferometry is proposed as a probe of the spatial configuration of two-Neutron haloes. After exploring the sensitivity of interferometry to the n-N configuration, it is demonstrated that the application of the standard method for constructing the correlation function is not valid for halo neutrons. A new iterative method is presented and applied to measurements of the dissociation of 6He, 11Li and 14Be. The correlation functions for these systems have thus been extracted for the first time and the corresponding root-Mean-Square n-n separations estimated. The results are in agreement with the predictions of available three-Body models

Identification of the doubly-magic nucleus 100Sn in the reaction 112Sn+natNi at 63 MeV/nucleon

Abstract We report on the production of the doubly-magic nucleus 100 Sn and other proton-rich nuclei in the A ∼ 100 region in the reaction 112 Sn + nat Ni at 63 MeV/nucleon. The experiment was carried out using the high acceptance device SISSI and the Alpha and LISE3 spectrometers at GANIL. The identification of the reaction products ( A , Z and Q ) was made using the measurements of time-of-flight, energy-loss and kinetic energy.

Three-body correlations in Borromean halo nuclei

Three-body correlations in the dissociation of Borromean halo nuclei are explored for the first time using a technique based on intensity interferometry and Dalitz plots. As an example, the breakup of

Neutrons from the breakup of C-19

^{14}

Experimental evidence for the particle stability of 34Ne and 37Na

Be into

β-Delayed neutron emission of the isotopes 20C, 40,41,42P, 43,44S☆

^{12}

Identification of μs-isomers produced in the fragmentation of a 112Sn beam

Be+n+n by Pb and C targets is analysed. The combined treatment of n-n and core-n correlations permitted the halo n-n separation to be deduced together with the characteristics