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This study aims at investigating whether wages of workers entering positions entitled to employment protection are affected by the introduction of a two-tier labor market regime. Difference-in-differences estimators-also combined with propensity score matching-are applied to repeated cross section microdata to evaluate the impact of a reform deregulating the Italian labor market in 2003. The results are robust and show that after the policy implementation protected entrants experienced a reduction in earnings of about $$-$$ 4.5 %. [ABSTRACT FROM AUTHOR]

Light charged-particle multiplicities in the evaporation residue (ER) and fission (FF) channels from the reaction 200MeV 32S + 100Mo as well as ER and FF channel cross-sections have been measured and compared to the predictions of the statistical model (SM) to estimate the fission time scale. The statistical model fails in reproducing the whole set of data and no convincing estimate is possible. In particular, while pre-scission multiplicities can be reproduced, the model strongly overestimates proton and alpha particle multiplicities in the ER channel, irrespective of the SM input parameters and prescriptions used for the level density and the transmission coefficients. Same calculations performed on data from literature in the A $ \approx$ 150 and excitation energy Ex $ \approx$ 100-200 MeV region, for the ER channel, provide similar conclusions. These findings repropose the problem of the reliability of the SM in describing the compound-nucleus decay and have a relevant impact on the extraction of the fission delay time through the use of the SM. [ABSTRACT FROM AUTHOR]

Surface cleaning tools made of copper alloys are widely employed when sparks have to be avoided. On the other hand, copper residues may be left on the surface. It is not known whether such copper incrustation interferes with the performance of a painting system. Therefore, the aim of this paper is to evaluate the effect of steel surface treatment with copper-containing tools on the performance of a painting system. Painted samples pretreated with ferrous and copper-containing tools were submitted to corrosion tests. The performance was monitored by visual inspection and electrochemical impedance. The surfaces of unpainted samples were analyzed by energy dispersion spectroscopy (EDS) and the open circuit potentials were measured. It is shown that the residues left on the metallic surface due to the mechanical action of the cleaning tools did not interfere significantly with the performance of the painting system. [ABSTRACT FROM AUTHOR]

Abstract  This paper describes a Session Initiation Protocol (SIP) based solution for mobility management that provides seamless mobile multimedia services in a heterogeneous scenario where different radio access technologies are used (802.11/ WiFi, Bluetooth, 2.5G/3G networks). The solution relies on the so called “Session Border Controllers” which are now widely used in many commercial SIP telephony solutions, mainly to deal with NAT traversal. Session Border Controller functionality has been extended to support seamless mobility for multimedia applications. A prototype of the proposed solution focused on VoIP services has been implemented in a test bed which is able to perform seamless handovers (and NAT traversal) using the 802.11, Bluetooth and 3G (UMTS) access networks. Measurements results are reported which analyze the performance of the solution in a real world environment, using commercial WiFi and 3G services. [ABSTRACT FROM AUTHOR]

The total cross-section of 12C(α,γ)16O was measured for the first time by a direct and ungated detection of the 16O recoils. This measurement in inverse kinematics using the recoil mass separator ERNA in combination with a windowless He gas target allowed to collect data with high precision in the energy range E = 1.9 to 4.9 MeV. The data represent new information for the determination of the astrophysical S( E) factor. [ABSTRACT FROM AUTHOR]

The excitation energy above the breakup threshold of the α + d/6Li system, after the interaction of 6Li nuclei with a 208Pb target, was deduced from the invariant mass of the α + d system. Data were collected with a large-solid-angle detector set-up at four beam energies around the Coulomb barrier. The excitation of the 6Li nucleus above the breakup threshold (1.47 MeV) has a quite similar behavior at each measured beam energy and angle; it is peaked at ∼ 1 MeV above the threshold and shows an exponential decay on the high energy side, which is a clear signature of a direct breakup process. The experimental excitation energies are reproduced both in shape and absolute value by 1) fully quantum-mechanical Coupled-Channel calculations with coupling to discretized-continuum 6Li excitations, 2) semi-classical Coupled-Channel approach, where the relative motion is treated along a classical trajectory. [ABSTRACT FROM AUTHOR]

A 4&pie; light charged particle spectrometer, named 8&pie;LP, is in operation at the Laboratori Nazionali di Legnaro (Italy) for the study of the reaction mechanisms produced in low-energy heavy-ion reactions. The spectrometer has recently been used in a study of fission dynamics that involves the detection of light charged particles in the fission and evaporation residue channel in a system of intermediate fissility, as well as in a study of multinucleon transfer to heavy target. Data on the system 240 MeV [SUP32]S + [SUP100]Mo are presented. Dynamical effects extracted as a consequence of the comparison of the data to the statistical model calculations are discussed. [ABSTRACT FROM AUTHOR]

: The 32S + 100Mo and 36S + 96Mo fusionlike reactions were studied at incident energy of Elab = 298 MeV and 320 MeV, respectively, with the aim of probing the influence of the entrance channel charge asymmetry on the dipole γ-ray emission. The excitation energy and spin distribution of the compound nucleus created in these reactions were identical, the only difference being associated with the unequal charge asymmetry of the two entrance channels. High-energy γ-rays were detected in an array of 9 seven-pack BaF2 clusters. Coincidence with fusionlike residues detected in four PPAC ensured the selection of central reaction events. By studying the differential γ-ray multiplicity associated with the two reactions it was shown that the dipole strength excited in the compound nucleus increases with the entrance channel charge asymmetry. From the linearized spectra, the increase of the GDR γ-ray intensity was found to be ∼ 25% for the more charge asymmetric system. The results are discussed and compared with those of previous data obtained at different incident energies. [ABSTRACT FROM AUTHOR]

We report on the results obtained from the study of the32S +64Ni and32S +58Ni peripheral reactions at incident energies Elab = 288 MeV and Elab = 320 MeV, respectively. High-energy γ-rays were detected in an array of 8 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction events. All of the relevant reaction parameters were kept constant with the exception of the different initial dipole moment caused by the different entrance channel charge asymmetry. While for quasi-elastic events no N/ Z effect was observed in the differential γ-ray multiplicities of the two reactions, for deep-inelastic events a larger dipole γ-ray emission occurs during the more N/ Z asymmetric reaction. A theoretical interpretation based on a collective Bremsstrahlung analysis of the reaction dynamics is presented. [ABSTRACT FROM AUTHOR]

Light particles in coincidence with evaporation residues and heavy fragments have been measured by a 4π charged-particle detector at the INFN Laboratori Nazionali di Legnaro (Padua) for the 240 MeV32S +100Mo reaction leading to the132Ce composite system at 152 MeV of excitation energy. Energy spectra of the alpha-particles in coincidence with fission fragments were extracted for many correlation angles both in plane and out of plane. A prominent out-of-plane emission was observed, consistent with the pattern for the near-scission emission. From the fit to the spectra, the pre-scission alpha-particle multiplicity of 0.040±0.006 was obtained. This value is reproduced by the code PACE2 without the inclusion of a delay time for fission. The presence of fast fission, which could be responsible for this result, is discussed. [ABSTRACT FROM AUTHOR]

An excitation function of the ground-state γ0-ray capture transition in 12C (α,γ)16O at θγ = 90° was obtained in far geometry using six Ge detectors, where the study of the reaction was initiated in inverse kinematics involving a windowless gas target. The detectors observed predominantly the E1 capture amplitude. The data at E = 1.32 to 2.99 MeV lead to an extrapolated astrophysical S factor SE1( E0) = 90±15 keV b at E0 = 0.3 MeV (for the case of constructive interference between the two lowest E1 sources), in good agreement with previous works. However, a novel Monte Carlo approach in the data extrapolation reveals systematic differences between the various data sets such that a combined analysis of all available data sets could produce a biased estimate of the SE1( E0) value. As a consequence, the case of destructive interference between the two lowest E1 sources with SE1( E0) = 8±3 keV b cannot be ruled out rigorously. [ABSTRACT FROM AUTHOR]

The stopping power of atomic and molecular deuterons in 3He gas was measured over the range Ed = 10 to 100 keV using the 3He pressure dependence of the 3He(d,p) 4He reaction yield. At energies above 30 keV, the observed stopping power values are in good agreement with a standard compilation. However, near 18 keV the experimental values drop by a factor 50 below the extrapolated values of the compilation. In a simple model, the behavior is due to the minimum 1 s↦2 s electron excitation of the He target atoms (= 19.8 eV, corresponding to Ed = 18.2 keV), i.e. it is a quantum effect, by which the atoms become nearly transparent for the ions. [ABSTRACT FROM AUTHOR]

The energy loss of deuterons in 3He gas was measured at E d = 15 to 100 keV using the 3He pressure dependence of the 3He(d,p)4He cross-section at a given incident energy. At the highest energies, the observed energy loss is in good agreement with a standard compilation. However, with decreasing energy the experimental values drop steadily below the theoretical values and near E d = 18 keV they drop sharply (within 1 keV) reaching the domain of nuclear stopping power. This threshold behavior is due to the minimum 1 s → 2 s electron excitation of the He target atoms, i.e. it is a quantum effect. Some consequences are discussed. [ABSTRACT FROM AUTHOR]

For improved measurements of the key astrophysical reaction 12C(α,γ)16O in inverted kinematics, a recoil separator ERNA is being developed at the 4 MV Dynamitron tandem accelerator in Bochum to detect directly the 16O recoils with about 50% efficiency. Calculations of the ion beam optics including all filtering and focusing elements of ERNA are presented. Since the 12C projectiles and the 16O recoils have essentially the same momentum, and since the 12C ion beam emerging from the accelerator passes through a momentum filter (analysing magnet), the 12C ion beam must be as free as possible from 16O contamination for ERNA to succeed. In the present work, the 16O contamination was reduced from a level of 1 × 10−11 to a level below 2 × 10−29 by the installation of Wien filters both before and after the analysing magnet. The measurement of these and other beam specifications involved other parts of the final ERNA layout – sequentially a Wien filter, a 60˚ dipole magnet, another Wien filter, and a ΔE-E telescope. The setup led to a measured suppression factor of 5 × 10−18 for the 12C ion beam. The experiments also indicate that an almost free choice of the charge state for the 16O recoils is possible in the separator. [ABSTRACT FROM AUTHOR]

We report on the results obtained from the study of the 32S +74Ge deep inelastic reaction at incident energy E= 320 MeV. High-energy γ-rays were detected in an array of 6 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction events. In order to investigate the pre-equilibrium dipole strength excitation two independent analyses were performed. In the first analysis the energy spectra of the γ-rays were evaluated in the statistical model framework while in the second one the γ-ray fragment angular correlation with respect to the nuclear spin vector of the composite system was studied. Both methods indicate the excitation of dipole strength in the highly deformed dinucleus and provide dipole resonance parameter sets that are in good agreement with each other. [ABSTRACT FROM AUTHOR]

A 4π detection system sensitive to light charged particles is being developed at the Laboratori Nazionali di Legnaro (LNL) for the study of the reaction mechanisms produced in heavy-ion collisions at energies up to 20 A MeV. The 8πLP apparatus is a telescope assembly characterized by a large solid angle (90% of 4π) and high granularity (262 modules). Particle identification at low energy is obtained by combining π E-E, TOF and PSD techniques. Thresholds for particle identification range from 1 MeV for protons and 3 MeV for alpha-particles to about 2-3 A MeV for C ions. The system is fully operational for experiments. [ABSTRACT FROM AUTHOR]

γ-rays are measured in coincidence with the dissipative complex fragments from theCl +Ni reaction at 7.7 A MeV. Theoretical γ-ray coincidence spectra are determined through a fitting procedure using the contribution of the excited fragment statistical γ-decay calculated by means of the CASCADE code. Whereas the expected statistical spectra fit very well the data in the energy region E=2 to 8 MeV, above this energy another emission mechanism in addition to the statistical decay has to be considered in order to reproduce the experimental spectra. Simulations based on the Vlasov equation suggest that this emission could come from the decay of dipole strength excited in the intermediate dinuclear system. [ABSTRACT FROM AUTHOR]

The absolute cross section σ (E) of the radiative capture reaction p(7Be,γ)8B at the center-of-mass energy E = 992 keV has been measured using a radioactive 7Be ion beam and a windowless gas target system filled with H2 gas. The 8B residual nuclides were detected with a recoil separator consisting of momentum and velocity filters and a ΔE-E detector telescope. The 8B yield was observed concurrently with the 7Be + p elastic scattering yield, relating σ(E) to the Rutherford scattering cross section. The resulting value, σ(E) = 0.41 ± 0.11 μb, leads to an S(E) factor at zero energy of S(0) = 16 ± 4 eV b, in fair agreement with recommended values. [ABSTRACT FROM AUTHOR]

The loss of 8Li recoil nuclei in 7Li(d,p)8Li has been measured using different backings and 7LiF target thicknesses as well as different deuteron energies. The results confirm essentially recent TRIM calculations. The losses are large (about 13%) for the combination of thin targets and heavy backings at Ed=0.80 MeV and increase with decreasing deuteron energy. The implications on the cross sections for 7Li(d,p)8Li and 7Be(p,γ)8B are discussed. [ABSTRACT FROM AUTHOR]