S. Grévy

Collapse of the N=28 shell closure in (42)Si.

The energies of the excited states in very neutron-rich (42)Si and (41,43)P have been measured using in-beam gamma-ray spectroscopy from the fragmentation of secondary beams of (42,44)S at 39A MeV. The low 2(+) energy of (42)Si, 770(19) keV, together with the level schemes of (41,43)P, provides evidence for the disappearance of the Z=14 and N=28 spherical shell closures, which is ascribed mainly to the action of proton-neutron tensor forces. New shell model calculations indicate that (42)Si is best described as a well-deformed oblate rotor.

First observation of 54Zn and its decay by two-proton emission

The nucleus 54Zn has been observed for the first time in an experiment at the SISSI/LISE3 facility of GANIL in the quasifragmentation of a 58Ni beam at 74.5 MeV/nucleon in a (nat)Ni target. The fragments were analyzed by means of the ALPHA-LISE3 separator and implanted in a silicon-strip detector where correlations in space and time between implantation and subsequent decay events allowed us to generate almost background free decay spectra for about 25 different nuclei at the same time. Eight 54Zn implantation events were observed. From the correlated decay events, the half-life of 54Zn is determined to be 3.2(+1.8)(-0.8) ms. Seven of the eight implantations are followed by two-proton emission with a decay energy of 1.48(2) MeV. The decay energy and the partial half-life are compared to model predictions and allow for a test of these two-proton decay models.

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

Direct mass measurements of 19 B, 22 C, 29 F, 31 Ne, 34 Na and other light exotic nuclei

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

Be into

Direct Mass Measurements ofB19,C22,F29,Ne31,Na34and Other Light Exotic Nuclei

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Well Developed Deformation in 42Si

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

First direct observation of two protons in the decay of 45Fe with a time-projection chamber.

(E,\tau)

Two-proton radioactivity studies with 45Fe and 48Ni

of resonances formed in

Unveiling the intruder deformed 0

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