L. Casano

Backward Compton scattering of laser light against high-energy electrons: the LADON photon beam at Frascati

SummaryIn the present paper we present the experimental results obtained for the backscattering of laser light against the high-energy electrons stored in Adone with the laser cavity dumping technique. The characteristics of the obtained photon beam (LADON beam) are discussed and compared with the theoretical previsions given by the usual storage ring theory.RiassuntoIn questo articolo si presentano i risultati sperimentali ottenuti con la diffusione all’indietro di luce laser sugli elettroni circolanti in Adone usando la tecnica del «cavity dumping». Si discutono le caratteristiche del fascio di fotoni così prodotto (fascio LADON) e si paragonano i risultati con le previsioni teoriche fornite dall’usuale teoria degli anelli di accumulazione.

A critical review of the deuteron photodisintegration data between 10 and 120 MeV

Abstract Worldwide data on deuteron photodisintegration between 10 and 120 MeV have been analyzed and compared with the standard theory including MEC+IC contributions. No real effect can be envisaged for the breakdown of the current theory at intermediate energy.

Project GRAAL: the scientific case

SummaryBackward Compton scattering of laser light against the high-energy electrons circulating in storage rings has produced tagged beams of fully polarized high-energy gamma-rays with an intensity useful for the study of photoreactions. At the ESRF this technique will produce a beam of 1.5 GeV and an intensity of 107 photons per second. We discuss the technical characteristics of such a project and the scientific goals which can be achieved in the study of the electromagnetic transitions of the hardrons and the photoproduction of isobars and strange particles in nucleons and nuclei.

Deuteron photodisintegration with polarized photons at Eγ=19.8 MeV

Abstract The symmetry σ ( θ ) for the reaction 2 H(γ, n) p has been measured at nine angles for Eγ = 19.8 MeV. The source of monochromatic and linearly polarized γ -rays was the Frascati Ladon facility, obtained by Compton scattering of laser light against high-energy electrons. The experimental results are compared with theoretical calculations based on the Reidsoft-core and with the De Tourreil-Sprung (version B) interactions.

DEUTERON PHOTO-DISINTEGRATION WITH POLARISED PHOTONS IN THE ENERGY RANGE 30-50 MEV

Abstract The reaction d( γ , np) has been studied using the tagged and polarised LADON gamma ray beam at an energy 30–50 MeV to investigate the existence of narrow dibaryonic resonances recently suggested from the experimental measurements in a different laboratory. The beam was obtained by Compton back-scattering of laser light on the electrons of the storage ring ADONE. Photo-neutron yields were measured at five neutron angle υ n c.m. = 22°, 55.5°, 90°, 125° and 157° in the center of mass system. Our results do not support the existence of such resonances.

Measurement of the3He (γ, p)d total cross-section at 48.6 MeV

SummaryThe total cross-section for the3He(γ, p)d reaction has been measured at γ-ray energy 48.6MeV with the monochromatic LADON photon beam and a nearly 4π proton detector.

Physics with polarized photons

The role that polarization can play in the interaction of real and virtual photons with nuclear matter is considered. Linear, circular, and elliptical polarization are considered. Photodisintegration of the deuteron with linearly polarized photons is then examined, followed by use of circularly polarized photons with a polarized target. 30 refs., 4 figs. (LEW)

Experimental results for the Ladon photon beam at Frascati

This paper reports the experimental results obtained with reference to the beam intensity, energy resolution and polarization of the gamma beam of the LADON facility at Frascati.

Deuteron photodisintegration induced by monochromatic, linearly polarized gamma‐rays

Measurement of the asymmetry factor in D(γ,u2009np) is reported and the result is discussed in the framework of Partovi’s theory.