37,281 research outputs found
Binding-energy independence of reduced spectroscopic strengths derived from (p, 2p) and (p, pn) reactions with nitrogen and oxygen isotopes
A campaign of intermediate energy (300-450 MeV/u) proton-induced nucleon
knockout measurements in inverse kinematics has been recently undertaken at the
R 3 B/LAND setup at GSI. We present a systematic theoretical analysis of these
data with the aim of studying the quenching of the single-particle strengths
and its binding-energy dependence. For that, the measured semi-inclusive (p,
2p) and (p, pn) cross sections are compared with theoretical predictions based
on single-particle cross sections derived from a novel coupled-channels
formalism and shell-model spectroscopic factors. A systematic reduction of
about 20-30% is found, with a very limited dependence on proton-neutron
asymmetry.Comment: 8 pages, 3 figure
Description of the LiLi transfer reaction using structure overlaps from a full three-body model
Recent data on the differential angular distribution for the transfer
reaction Li(p,d)Li at MeV in inverse kinematics are
analysed within the DWBA reaction framework, using the overlap functions
calculated within a three-body model of Li. The weight of the different
Li configurations in the system's ground state is obtained from the
structure calculations unambiguously. The effect of the Li spin in the
calculated observables is also investigated. We find that, although all the
considered models succeed in reproducing the shape of the data, the magnitude
is very sensitive to the content of wave in the Li
ground-state wave function. Among the considered models, the best agreement
with the data is obtained when the Li ground state contains a 31\%
of wave in the -Li subsystem. Although this model takes into
account explicitly the splitting of the and resonances due to the
coupling of the wave to the spin of the core, a similar
degree of agreement can be achieved with a model in which the Li spin is
ignored, provided that it contains a similar p-wave content.Comment: 8 pages, 3 figures. Final versio
Investigating the 10Li continuum through 9Li(d,p)10Li reactions
The continuum structure of the unbound system Li, inferred from the
LiLi transfer reaction, is reexamined. Experimental data for
this reaction, measured at two different energies, are analyzed with the same
reaction framework and structure models. It is shown that the seemingly
different features observed in the measured excitation energy spectra can be
understood as due to the different incident energy and angular range covered by
the two experiments. The present results support the persistence of the
parity inversion beyond the neutron dripline as well as the splitting of the
well-known low-lying -wave resonance. Furthermore, they provide indirect
evidence that most of the single-particle strength, including possible
resonances, lies at relatively high excitations energies.Comment: accepted for publication in Physics Letters
K- absorption in nuclei by two and three nucleons
It will be shown that the peaks in the (Lambda p) and (Lambda d) invariant
mass distributions, observed in recent FINUDA experiments and claimed to be
signals of deeply bound kaonic states, are naturally explained in terms of K-
absorption by two or three nucleons leaving the rest of the original nuclei as
spectator. For reactions on heavy nuclei, the subsequent interactions of the
particles produced in the primary absorption process with the residual nucleus
play an important role. Our analyses leads to the conclusion that at present
there is no experimental evidence of deeply bound K- state in nuclei. Although
the FINUDA experiments have been done for reasons which are not supported a
posteriori, some new physics can be extracted from the data.Comment: 6 pages, 5 figures. Talk presented at the International Conference on
Exotic Atoms "EXA 2008", Vienna, Austria, September 15-18, 200
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