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I consumi di energia elettrica del CNR
Get PDFQuesto rapporto raccoglie tutti i dati sull’impiego di energia elettrica in tutte le strutture del CNR nel periodo dal 2010 al 2022 (consumi e costi) e fornisce informazioni utili per la contrattualistica energetica. L’elenco delle utenze elettriche è aggiornato al 30 settembre 2023
Giant Pairing Vibration in the continuum beyond RPA
Get PDFThe possibility of the existence of collective pairing modes (Jπ =
0+) lying at high excitation energy (10-15 MeV) resulting from the correlated two-particle or two-hole excitation across major shells, was formulated in the 70’s by Bes and Broglia, and today these modes are known as the Giant Pairing Vibrations (GPV). Since then there have been numerous unsuccessful attempts to detect them, and recently a bump has been reported in the excitation spectrum of 14C produced by the reaction 12C(18O,16O)14C, that was proposed to be a signature of the GPV. In this contribution we present a microscopic calculation of the response function of 12C to the creation operator of two neutrons coupled to 0+, including the coupling to the continuum. We carry out a pp-RPA calculation, obtaining a concentration of ∗ below threshold in reasonable agreement with the two observed discrete excited 0+∗≈ 13 MeV) based on s and d orbitals, which displays the general features expected for a GPV. We then take into account the coupling between the neutron degrees of freedom and the low-lying collective quadrupole vibrations of the core, that shifts and fragments the sd strength, producing two states strength close to threshold (E states, as well as a bump in the continuum (E ≈ 18 MeV)
Axial quadrupole and octupole dynamics in heavy even-even nuclei
Get PDFA phenomenological geometrical model is proposed to describe col- lective states in even-even nuclei with quadrupole and octupole deformation. The model is applied for a systematic description of the rotation-vibration dynamics associated with the alternate parity bands observed in the isotopic chains of Ra, Th, U, and Pu nuclei. As a result, the A = 224–228 mass region of the Ra and Th nuclei was identified as critical for the transition between dynamic and static octupole deformation, which commences at different spins. The model also predicts a specific spin dependence for the transition probabilities in these critical nuclei
Investigation of transfer reactions at 15 MeV/u in a multi-channel approach within the NUMEN project
Get PDFA full-comprehensive study of heavy-ion induced nuclear reac- tions is a powerful tool to characterize nuclear mean-field features as well as few- nucleon correlations in low-lying nuclear states. In this context, the investigation of 76Se(18O, 17O)75Se and 76Se(18O, 19F)75As transfer reactions was performed with the NUMEN project, aiming at providing data-driven information to constrain nu- clear structure models for the 76Se nucleus. This nucleus is under investigation since it is the daughter nucleus of 76Ge in the neutrinoless double beta decay (0νββ) pro- cess. The experiment was performed at INFN-LNS where the 18O beam impinged the 76Se target and the reaction ejectiles were momentum analyzed by the MAGNEX magnetic spectrometer
Elastic scattering angular distribution for the 18O+48Ti collision at 275 MeV within the NUMEN project
Get PDFIn the context of the NUMEN pro ject, the 18 O + 48 Ti collision at 275 MeV incident energy was studied for the first time. In the adopted multichannel approach, the elastic scattering was measured in order to deduce the initial state interaction and the corresponding optical potential. The angular distribution of elastic scattering was determined across a wide range of scattering angles
The pygmy dipole resonance in Sn isotopes studied with the Oslo method
Get PDFThe evolution of bulk properties of the low-lying electric dipole response (LEDR) in 111−113,116−122,124Sn has been studied on the basis of the γ-ray strength functions extracted from particle-γ coincidence data with the Oslo method and from Coulomb excitation data. The LEDR was found to be concentrated at ≈ 8.0–8.3 MeV and exhausts ≈ 2–3% of the Thomas-Reiche-Kuhn sum rule in all isotopes. No clear increase of the strength from the lightest 111Sn to the heaviest studied 124Sn, predicted with the majority of theoretical approaches, was observed
Study of Gamow-Teller giant resonance in 11Li drip-line nucleus
Get PDFGamow-Teller (GT) transitions in an exotic neutron-rich nucleus 11Li have been measured via the 11Li(p,n)11Be reaction at 182 MeV/u in inverse kinematics at RI Beam Factory (RIBF) of RIKEN Nishina Center. The neutron detector array PANDORA and the SAMURAI spectrometer were used to detect recoil neutrons and decay products produced in the (p,n) reaction, respectively. Preliminary results of kinematic correlation of recoil neutrons, corresponding to GT transitions, are presented for several decay channels of 11Be reaction product. Four- teen decay channels with light-particle emission from 11Be excited states, including seven new channels, are identified, in addition to the non-particle-emission channel from 11Be ground or low-lying states
A new approach to nuclear level densities: The QRPA plus boson expansion
Get PDFNuclear level densities play a key role in many nuclear applications. To go beyond the usual particle-independent approximation, a conceptually new approach based on the boson expansion of QRPA excitations is described. The calculated nuclear level densities are shown to follow an energy dependence close to a constant-temperature formula at energies above a few MeV, but present a rather narrow spin distribution. A quite remarkable agreement is obtained with experimental s-wave resonance spacings and Oslo data, at least for the 48 even-even nuclei considered in the present study
Status of the ELIADE γ-ray spectrometer for NRF Experiments at ELI-NP
Get PDFThe ELIADE γ-ray spectrometer constructed at the Extreme Light Infrastructure Nuclear Physics (ELI-NP, Romania) is featured for Nuclear Reso- nance Fluorescent studies to be performed using a mono-energetical almost fully polarized γ-ray beam. This paper reports on the progress of implementation of ELIADE
The physics of ultra-high-energy cosmic rays in the context of the Pierre Auger Observatory: Main results and future perspectives
Get PDFFor almost 20 years, the Pierre Auger Observatory has studied ultra- high-energy cosmic rays (UHECRs) using its unique hybrid design, which employs a ground array of water-Cherenkov detectors along with 27 fluorescence telescopes to observe extensive air showers with different, complementary techniques. Some fundamental results include measurements of the energy spectrum, of the primary mass composition and of the arrival directions with unprecedented accuracy. Al- though no specific source has been pinpointed yet, these findings have significantly improved our understanding of UHECR and set the stage for the upgrade of the experimental setup, called AugerPrime, currently under finalization