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In this proceeding we report on alpha particle emission through the nuclear break-up in the reaction 40Ca on a 40Ca target at 50A MeV. It is observed that alpha particles are emitted to the continuum with very specific angular distribution during the reaction. The alpha particle properties seem to be compatible with an alpha cluster in the daughter nucleus that is perturbed by the short range nuclear attraction of the collision partner and emitted as described by a time-dependent theory. This mechanism offers new possibilities to study alpha particle properties in the nuclear medium. [ABSTRACT FROM AUTHOR]

Inelastic scattering of 40Ca on 40Ca at 50 A.MeV has been measured in coincidence with protons at the GANIL facility using a very performant set-up. The SPEG spectrometer was associated with 240 CsI(Tl) scintillators of the INDRA 4π array, allowing for the measurement of complete decay events. The missing energy method was applied to these events to study the particle decay of collective states. For events with excitation energy between 42 and 55 MeV, a direct decay branch by three protons towards the low energy states of 37Cl gives the first evidence for a 3-phonon giant resonance state. A significant direct decay branch by alpha-particles of the GQR is also measured for the first time. [Copyright &y& Elsevier]

Abstract: Inelastic scattering of 40Ca on 40Ca at has been measured at the GANIL facility in coincidence with light charged particles. For the first time, the SPEG spectrometer was associated with 240 CsI(Tl) scintillators of the INDRA 4π array. The missing energy method, successfully used in previous experiments to study the nucleon decay of collective states is applied to the study of alpha-particle decay of the GQR. A significant direct decay branch by alpha-particles of the GQR in 40Ca is measured for the first time. [Copyright &y& Elsevier]

The EUSO experiment is currently under study by ESA for a possible installation on the International Space Station. The experiment is designed to study, by means of a space-based observational apparatus, the Extensive Air Showers produced in the atmosphere by Extreme High-Energy Cosmic Rays. The design of a fast, single-photon sensitive photo-detector in the near UV, covering a large area with a few hundreds thousands pixels, and suitable for 3 years of operation in space is a challenging task. The basic aspects of the current EUSO photo-detector design, based on the presently known requirements and constraints, and the results of the preliminary studies carried on so far will be described. [Copyright &y& Elsevier]

A simple formalism describing the light response of CsI(Tl) to heavy ions, which quantifies the luminescence and the quenching in terms of the competition between radiative transitions following the carrier trapping at the Tl activator sites and the electron–hole recombination, is proposed. The effect of the δ-rays on the scintillation efficiency is for the first time quantitatively included in a fully consistent way. The light output expression depends on four parameters determined by a procedure of global fit to experimental data. [Copyright &y& Elsevier]

The light output of the 324 CsI(Tl) scintillators of INDRA has been measured over large ranges in energy: 1–80 AMeV and in atomic number of incident ions: Z=1–60. An analytical expression for the non-linear total light response as a function of the energy and the identity of the ion is developed. It depends on four parameters. For three of them, connected to CsI(Tl) intrinsic characteristics, fixed values are proposed. Two applications are presented: energy calibration and fragment identification in telescopes using a CsI(Tl) crystal as residual energy detector. [Copyright &y& Elsevier]

Abstract: It is most likely that the next generation of experiments for the study of the Ultra High-Energy Cosmic Radiation (UHECR), that is cosmic particles reaching the Earth with energies in excess of , will consist of space-based experiments. The observation from space of the Extensive Atmospheric Showers (EAS) produced by UHECR is a big challenge, because the faint signal must be extracted from a large background by an experimental apparatus operating in space. The requirements for the photo-detector for such a kind of space missions will be briefly discussed and the solutions adopted for the design of the photo-detector of the EUSO experiment will be presented. [Copyright &y& Elsevier]