Mariano Vigilante

Bio: Mariano Vigilante is an academic researcher from University of Naples Federico II. The author has contributed to research in topics: Nucleon & Neutron. The author has an hindex of 30, co-authored 231 publications receiving 2876 citations. Previous affiliations of Mariano Vigilante include Istituto Nazionale di Fisica Nucleare.

Results of the ASY-EOS experiment at GSI: The symmetry energy at suprasaturation density

Abstract: Directed and elliptic flows of neutrons and light charged particles were measured for the reaction 197Au+197Au at 400 MeV/nucleon incident energy within the ASY-EOS experimental campaign at the GSI laboratory. The detection system consisted of the Large Area Neutron Detector LAND, combined with parts of the CHIMERA multidetector, of the ALADIN Time-of-flight Wall, and of the Washington-University Microball detector. The latter three arrays were used for the event characterization and reaction-plane reconstruction. In addition, an array of triple telescopes, KRATTA, was used for complementary measurements of the isotopic composition and flows of light charged particles. From the comparison of the elliptic flow ratio of neutrons with respect to charged particles with UrQMD predictions, a value \gamma = 0.72 \pm 0.19 is obtained for the power-law coefficient describing the density dependence of the potential part in the parametrization of the symmetry energy. It represents a new and more stringent constraint for the regime of supra-saturation density and confirms, with a considerably smaller uncertainty, the moderately soft to linear density dependence deduced from the earlier FOPI-LAND data. The densities probed are shown to reach beyond twice saturation.

Particle identification using the (DELTA)E-E technique and pulse shape discrimination with the silicon detectors of the FAZIA project

Abstract: The response of silicon-silicon-CsI(Tl) and silicon-CsI(Tl) telescopes to fragments produced in nuclear interactions has been studied. The telescopes were developed within the FAZIA collaboration. The capabilities of two methods are compared: (a) the standard ΔE-E technique and (b) the digital Pulse Shape Analysis technique (for identification of nuclear fragments stopped in a single Si-layer). In a test setup, nuclear fragments covering a large range in nuclear charge, mass and energy were detected. They were produced in nuclear reactions induced by a 35A MeV beam of 129Xe impinging on various targets. It was found that the ΔE-E correlations allow the identification of all isotopes up to Z∼25. With the digital Pulse Shape Analysis it is possible to fully distinguish the charge of stopped nuclei up to the maximum available Z (slightly over that of the beam, Z=54).

Isotopic Scaling and the Symmetry Energy in Spectator Fragmentation

Abstract: Isotopic effects in the fragmentation of excited target residues following collisions of $^{12}$C on $^{112,124}$Sn at incident energies of 300 and 600 MeV per nucleon were studied with the INDRA 4$\pi$ detector. The measured yield ratios for light particles and fragments with atomic number $Z \leq$ 5 obey the exponential law of isotopic scaling. The deduced scaling parameters decrease with increasing centrality to values as low as $\alpha = 0.25 \pm 0.02$ for the central event group at 600 MeV per nucleon. Symmetry term coefficients, deduced from these data within the statistical description of isotopic scaling, are near $\gamma =$ 25 MeV for peripheral and $\gamma <$ 10 MeV for central collisions.

Characteristics of the fragments produced in central collisions of129Xe+natSnfrom 32Ato 50AMeV

Abstract: Characteristics of the primary fragments produced in central collisions of ${}^{129}\mathrm{Xe}{+}^{\mathrm{nat}}\mathrm{Sn}$ from 32 to 50 A MeV have been obtained. By using the correlation technique for the relative velocity between light charged particles (LCP) and fragments, we were able to extract the multiplicities and average kinetic energy of secondary evaporated LCP. We then reconstructed the size and excitation energy of the primary fragments. For each bombarding energy a constant value of the excitation energy per nucleon over the whole range of fragment charge has been found. This value saturates at 3A MeV for beam energies 39A MeV and above. The corresponding secondary evaporated LCP represent less than 40% of all produced particles and decreases down to 23% for 50A MeV. The experimental characteristics of the primary fragments are compared to the predictions of statistical multifragmentation model (SMM) calculations. Reasonable agreement between the data and the calculation has been found for any given incident energy. However SMM fails to reproduce the trend of the excitation function of the primary fragment excitation energy and the amount of secondary evaporated LCP's.

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Transition probability from the ground to the first-excited 2^+ state of even-even nuclides

Abstract: Adopted values for the reduced electric quadrupole transition probability, B(E2)↑, from the ground state to the first-excited 2+ state of even–even nuclides are given in Table I. Values of τ, the mean life of the 2+ state; E, the energy; and β, the quadrupole deformation parameter, are also listed there. The ratio of β to the value expected from the single-particle model is presented. The intrinsic quadrupole moment, Q0, is deduced from the B(E2)↑ value. The product E×B(E2)↑ is expressed as a percentage of the energy-weighted total and isoscalar E2 sum-rule strengths. Table II presents the data on which Table I is based, namely the experimental results for B(E2)↑ values with quoted uncertainties. Information is also given on the quantity measured and the method used. The literature has been covered to November 2000. The adopted B(E2)↑ values are compared in Table III with the values given by systematics and by various theoretical models. Predictions of unmeasured B(E2)↑ values are also given in Table III.