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New cross sections of the partial ( $$\gamma ,1n)$$ , ( $$\gamma ,2n)$$ , and ( $$\gamma $$ , 3n) and total ( $$\gamma $$ , Sn), and ( $$\gamma $$ , tot) photoneutron reactions for $$^{{206,207}}$$ Pb were evaluated using the experimental-theoretical method. The evaluation procedure was based on the comparison in detail of $$^{{206,207}}$$ Pb data obtained only at Livermore (USA) with $$^{{208}}$$ Pb data obtained at Livermore, Saclay (France) and also in other experiments. It was found that in the cases of all $$^{{206,207,208}}$$ Pb isotopes clear disagreements between Livermore data and new evaluated data can be explained by the assumption of loss of many neutrons in experimental ( $$\gamma $$ , 1n) reaction cross sections. It was shown that Livermore experimental data for $$^{{206,207,208}}$$ Pb as well as for $$^{{75}}$$ As, $$^{{127}}$$ I, and $$^{{181}}$$ Ta investigated before are not reliable.

We report on how to tackle the problem of establishing a chiral effective field theory in nuclear matter with explicit pion fields and in the presence of external sources (Ann. Phys. 297, 27 (2002)). We have made use of the results of J.A. Oller (Phys. Rev. C 65, 025204 (2002)) where the generating functional for the in-medium chiral SU(2) x SU(2) Lagrangian has been derived. Within this approach we develop the so-called standard power counting rules for the calculation of in-medium pion properties if the residual nucleon energies are of the order of the pion mass. In addition, for the case of vanishing residual nucleon energies, a modified scheme (non-standard counting) is introduced. For both schemes the pertinent scales where the chiral expansions have to break down are established as well. We have performed a systematic analysis of n-point in-medium Green functions up to and including next-to-leading order when the standard rules apply. These include the in-medium contributions to quark condensates, pion propagators, pion masses and couplings of the axial-vector, vector and pseudoscalar currents to pions.

Neutron production by stopping 55 MeV deuterons in thick carbon and heavy-water targets has been measured by the activation method. The geometry was close to the one defined for the SPIRAL2 uranium-carbide target in the initial phase. A comparative method for obtaining the neutron flux has been used and is presented in detail. The neutron flux generated by 55 MeV deuterons on carbon is 2.3 times the flux at the deuteron energy of 40 MeV. The flux further increases by a factor 1.4 when using a heavy-water target. These results are discussed in the context of an energy upgrade of the SPIRAL2 driver accelerator.

The objective of DEAR (DAΦNE Exotic Atom Research) is the measurement of the K α line shift and width, due to the strong interaction, in kaonic hydrogen and a similar measurement - the first one - in kaonic deuterium. The aim is a precision determination of the antikaon-nucleon isospin dependent scattering lengths in order to obtain the kaon nucleon sigma terms. In a first phase, dedicated to the calibration and optimization of the setup, the experiment collected data on kaonic nitrogen: for the first time a complex of three transitions (7 → 6 at 4.6 keV, 6 → 5 at 7.6 keV and 5 → 4 at 14 keV) was measured, and the corresponding yields obtained. The kaonic hydrogen measurement was performed for a total integrated luminosity of about 60 pb-1 in the last months of the 2002 year. Data analyses are in progress, preliminary results being hereby presented, together with those on kaonic nitrogen. PACS: 36.10.-K – 36.10.Gv

New results on the longitudinal inclusive spin asymmetry A 1 d in the range 1 < Q 2 < 100(GeV/c)^2 and 0.004 < x < 0.7 are presented. From these results we derive the spin-dependent structure function g 1 d which we use to evaluate the scale-invariant flavor-singlet axial charge $ \hat{{a}}_{0}^{}$ . The contribution of the measured region is evaluated by a QCD fit of the world data. The data were obtained by the COMPASS experiment at CERN using a 160GeV polarized muon beam scattered off a large double-cell polarized 6LiD target. The results are in agreement with those from previous experiments and improve considerably the statistical accuracy in the region x < 0.03.

The theoretical model, successfully employed to describe in a single picture the non-equilibrium component and the evaporation component of the angular correlation between particles and reaction residues emitted in a peripheral heavy-ion collision for various nuclear systems and in a wide energy range, is here revisited to keep into account the different dynamical dispersion in near-side and far-side trajectories. This new approach, applied to the C- $ \alpha$ differential multiplicities for the 16O$ + $58Ni at 6MeV/A and 16O$ + $48Ti at 8.3MeV/A deep inelastic collisions, allows to explain more in detail the reaction mechanism of such processes.

We show that the photoexcitation of the nonexotic members baryon antidecuplet, suggested by the soliton classification of low-lying baryons, is strongly suppressed on the proton target. The process occurs mostly on the neutron target. This qualitative prediction can be useful in identifying the nonexotic members of the antidecuplet in the known baryon spectrum. We also analyze the interrelation between photocouplings of various baryon multiplets in the soliton picture and in the nonrelativistic quark model.

The high-spin states in 141Nd were investigated using the 96Zr(48Ca, 3n) reaction and the EUROBALL array. The level scheme has been extended up to an excitation energy of around 16MeV and spin 81/2. Two new bands of dipole transitions and three bands presumably of quadrupole transitions were identified and their connections to low-lying states were established. Cranked Nilsson-Strutinsky and tilted axis cranking calculations are combined in the interpretation of the observed dipole bands. The high-spin bands with assigned quadrupole transitions are interpreted as triaxial bands, while the dipole bands appear in the calculations to exhibit a shape evolution from low-deformation triaxial to spherical shape. They can be classified as magnetic rotation, with transition probabilities that show the characteristic decrease with angular momentum caused by the shears mechanism.

The integral measurement of the 12C(n, p)12B reaction was performed at the neutron time-of-flight facility n_TOF at CERN. The total number of 12B nuclei produced per neutron pulse of the n_TOF beam was determined using the activation technique in combination with a time-of-flight technique. The cross section is integrated over the n_TOF neutron energy spectrum from reaction threshold at 13.6MeV to 10GeV. Having been measured up to 1GeV on basis of the 235U(n, f ) reaction, the neutron energy spectrum above 200MeV has been re-evaluated due to the recent extension of the cross section reference for this particular reaction, which is otherwise considered a standard up to 200MeV. The results from the dedicated GEANT4 simulations have been used to evaluate the neutron flux from 1GeV up to 10GeV. The experimental results related to the 12C(n, p)12B reaction are compared with the evaluated cross sections from major libraries and with the predictions of different GEANT4 models, which mostly underestimate the 12B production. On the contrary, a good reproduction of the integral cross section derived from measurements is obtained with TALYS-1.6 calculations, with optimized parameters.