1,358 research outputs found
I beni culturali di interesse religioso nella nuova legislazione statale: le innovazioni nell'Intesa con la Conferenza episcoipale italiana
La nuova Intesa tra il Ministro per i Beni e le Attivit\ue0 culturali ed il Presidente della Conferenza episcopale italiana si \ue8 resa necessaria a seguito dell\u2019entrata in vigore del d.lgs. 22 gennaio 2004, n. 42 (Codice dei beni culturali e del paesaggio) e della l. cost. 18 ottobre 2001, n. 3 (modifiche al Titolo V della Costituzione).
Sul piano strutturale il documento, in diverse circostanze, ripropone i contenuti sostanziali dell\u2019Intesa del 1996 (che trascurer\uf2 in quanto diffusamente trattati dalla dottrina) ma in pi\uf9 punti \uabaggiorna\ubb e \uabintegra\ubb, per usare la stessa terminologia adottata in sede di sottoscrizione, i contenuti della precedente Intesa. Pertanto in questa sede cercher\uf2 di evidenziare e circoscrivere alcune criticit\ue0 di sistema, se tali saranno anche nelle applicazioni, in rapporto alle intervenute innovazioni legislative
Polarization Asymmetry In The Photodisintegration Of The Deuteron
The reaction ²(γ,p)n has been studied using a monochromatic and polarized gamma ray beam at energies E(γ)=19.8, 29.0, 38.6, and 60.8 MeV. The beam of an intensity ∼4×10⁵ γ/sec was obtained by Compton back scattering of mode-locked laser light off electron bunches in the Adone storage ring. Photoneutron yields were measured at nine neutron angles thetan≃15, 30, 45, 60, 90, 120, 135, 150, and 165 deg in the center of mass (c.m.) for E(γ)=19.8, 29.0, and 38.6 MeV, and at thetan≃30, 60, 90, 120, and 150 deg c.m. for E(γ)=60.8 MeV. The polarization independent component Iₒ(theta) of the differential cross section and the polarization dependent component PI₁(theta) were deduced and the angular distribution of the azimuthal asymmetry factor Σ(theta)=I₁(theta)/Iₒ(theta) was obtained. An extensive comparison with theory has been carried out and the inclusion of corrections due to meson exchange currents and to Δ-isobar configurations have been shown to be mandatory at energies E(γ)≳40 MeV. Theoretical and experimental implications of intermediate energy deuteron photo- disintegration studies are discussed in some detail
Polarization Asymmetry In The Photodisintegration Of The Deuteron
The reaction ²(γ,p)n has been studied using a monochromatic and polarized gamma ray beam at energies E(γ)=19.8, 29.0, 38.6, and 60.8 MeV. The beam of an intensity ∼4×10⁵ γ/sec was obtained by Compton back scattering of mode-locked laser light off electron bunches in the Adone storage ring. Photoneutron yields were measured at nine neutron angles thetan≃15, 30, 45, 60, 90, 120, 135, 150, and 165 deg in the center of mass (c.m.) for E(γ)=19.8, 29.0, and 38.6 MeV, and at thetan≃30, 60, 90, 120, and 150 deg c.m. for E(γ)=60.8 MeV. The polarization independent component Iₒ(theta) of the differential cross section and the polarization dependent component PI₁(theta) were deduced and the angular distribution of the azimuthal asymmetry factor Σ(theta)=I₁(theta)/Iₒ(theta) was obtained. An extensive comparison with theory has been carried out and the inclusion of corrections due to meson exchange currents and to Δ-isobar configurations have been shown to be mandatory at energies E(γ)≳40 MeV. Theoretical and experimental implications of intermediate energy deuteron photo- disintegration studies are discussed in some detail
The Cosmic-Ray Proton and Helium Spectra measured with the CAPRICE98 balloon experiment
A new measurement of the primary cosmic-ray proton and helium fluxes from 3
to 350 GeV was carried out by the balloon-borne CAPRICE experiment in 1998.
This experimental setup combines different detector techniques and has
excellent particle discrimination capabilities allowing clear particle
identification. Our experiment has the capability to determine accurately
detector selection efficiencies and systematic errors associated with them.
Furthermore, it can check for the first time the energy determined by the
magnet spectrometer by using the Cherenkov angle measured by the RICH detector
well above 20 GeV/n. The analysis of the primary proton and helium components
is described here and the results are compared with other recent measurements
using other magnet spectrometers. The observed energy spectra at the top of the
atmosphere can be represented by (1.27+-0.09)x10^4 E^(-2.75+-0.02) particles
(m^2 GeV sr s)^-1, where E is the kinetic energy, for protons between 20 and
350 GeV and (4.8+-0.8)x10^2 E^(-2.67+-0.06) particles (m^2 GeV nucleon^-1 sr
s)^-1, where E is the kinetic energy per nucleon, for helium nuclei between 15
and 150 GeV nucleon^-1.Comment: To be published on Astroparticle Physics (44 pages, 13 figures, 5
tables
Antimatter research in Space
Two of the most compelling issues facing astrophysics and cosmology today are
to understand the nature of the dark matter that pervades the universe and to
understand the apparent absence of cosmological antimatter. For both issues,
sensitive measurements of cosmic-ray antiprotons and positrons, in a wide
energy range, are crucial. Many different mechanisms can contribute to
antiprotons and positrons production, ranging from conventional reactions up to
exotic processes like neutralino annihilation. The open problems are so
fundamental (i.e.: is the universe symmetric in matter and antimatter ?) that
experiments in this field will probably be of the greatest interest in the next
years. Here we will summarize the present situation, showing the different
hypothesis and models and the experimental measurements needed to lead to a
more established scenario.Comment: 10 pages, 7 figures, Invited talk at the 18th European Cosmic Ray
Symposium, Moscow, July 2002, submitted to Journal of Physics
Accelerator Testing of the General Antiparticle Spectrometer, a Novel Approach to Indirect Dark Matter Detection
We report on recent accelerator testing of a prototype general antiparticle
spectrometer (GAPS). GAPS is a novel approach for indirect dark matter searches
that exploits the antideuterons produced in neutralino-neutralino
annihilations. GAPS captures these antideuterons into a target with the
subsequent formation of exotic atoms. These exotic atoms decay with the
emission of X-rays of precisely defined energy and a correlated pion signature
from nuclear annihilation. This signature uniquely characterizes the
antideuterons. Preliminary analysis of data from a prototype GAPS in an
antiproton beam at the KEK accelerator in Japan has confirmed the
multi-X-ray/pion star topology and indicated X-ray yields consistent with prior
expectations. Moreover our success in utilizing solid rather than gas targets
represents a significant simplification over our original approach and offers
potential gains in sensitivity through reduced dead mass in the target area.Comment: 18 pages, 9 figures, submitted to JCA
Detection of the high energy component of Jovian electrons in Low Earth Orbit with the PAMELA experiment
The PAMELA experiment is devoted to the study of cosmic rays in Low Earth
Orbit with an apparatus optimized to perform a precise determination of the
galactic antimatter component of c.r. It is constituted by a number of
detectors built around a permanent magnet spectrometer. PAMELA was launched in
space on June 15th 2006 on board the Russian Resurs-DK1 satellite for a mission
duration of three years. The characteristics of the detectors, the long
lifetime and the orbit of the satellite, will allow to address several aspects
of cosmic-ray physics. In this work we discuss the observational capabilities
of PAMELA to detect the electron component above 50 MeV. The magnetic
spectrometer allows a detailed measurement of the energy spectrum of electrons
of galactic and Jovian origin. Long term measurements and correlations with
Earth-Jupiter 13 months synodic period will allow to separate these two
contributions and to measure the primary electron Jovian component, dominant in
the 50-70 MeV energy range. With this technique it will also be possible to
study the contribution to the electron spectrum of Jovian e- reaccelerated up
to 2 GeV at the Solar Wind Termination Shock.Comment: On behalf of PAMELA collaboration. Accepted for publication on
Advances in Space Researc
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