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Spallation is one of possible scenarios of proton - nucleus reaction considered nowadays. Pions are the most abundantly produced mesons during the reactions. Boltzmann-Uehling-Uhlenbeck (BUU) model was used to describe pion spectra, results will be presented.

In order to shorten the time of through-the-canopy-ejection, and to ensure pilot safely escape and survive. The application of linear cutting technique using miniature detonation cord( MDC) in through-the-canopy-ejection-system is proposed. A series of different kinds of MDC are designed. Firstly experimental study on the cutting process of the PMMA plate wiht MDC is carried out. Material of metal cover explosive types and the range of charge quantities are determined. Consequently the phenomena of spallation is observed, and the relationship between the cutting depth and charge quantities is obtained. For the comparison, the process of explosion cutting PMMA plate is simulated by means of nonlinear dynamic analysis code LS-DYNA. Spallation phenomena which occurs in the experiment, is also observed in the simulation. Simulation results present the relationship of cutting depth of PMMA plate versus charge linear density, which well agree with experimental ones.

A brief review is given of the development of linacs, cyclotrons, synchrotrons (also accumulators) and FFAG accelerators for a variety of high power hadron beam applications.

Spallation neutron sources are the primary accelerator-driven source of intense neutrons. They require high power proton accelerators in the GeV energy range coupled to heavy metal targets for efficient neutron production. They form the basis of large scale neutron scattering facilities, and are essential elements in accelerator-driven subcritical reactors. Demanding technology has been developed which is enabling the next generation of spallation neutron sources to reach even higher neutron fluxes. This technology sets the stage for future deployment in accelerator-driven systems and neutron sources for nuclear material irradiation.

In order to reveal the underlying mechanism governing the failure of solids subjected to impact loading, this paper presents a closed trans-scale formulation and numerical simulation of damage evolution to macroscopic failure, in particular to spallation. The trans-scale formulation consists of equations of continuum, momentum, and microdamage evolution, in which there are several time scales and length scales on meso- and macroscopic levels. With this formulation, numerical simulation on spallation is performed. The effects of several predominate dimensionless parameters, such as imposed and intrinsic Deborah numbers, on spallation are discussed.

A brief review is given of the development of linacs, cyclotrons, synchrotrons (also accumulators) and FFAG accelerators for a variety of high power hadron beam applications.

In order to shorten the time of through-the-canopy-ejection, and to ensure pilot safely escape and survive. The application of linear cutting technique using miniature detonation cord(MDC) in through-the-canopy-ejection-system is proposed. A series of different kinds of MDC are designed. Firstly experimental study on the cutting process of the PMMA plate with MDC is carried out. Material of metal cover explosive types and the range of charge quantities are determined. Consequently the phenomena of spallation is observed, and the relationship between the cutting depth and charge quantities is obtained. For the comparison, the process of explosion cutting PMMA plate is simulated by means of nonlinear dynamic analysis code LS-DYNA. Spallation phenomena which occurs in the experiment, is also observed in the simulation. Simulation results present the relationship of cutting depth of PMMA plate versus charge linear density, which well agree with experimental ones.

Spallation neutron sources are the primary accelerator-driven source of intense neutrons. They require high power proton accelerators in the GeV energy range coupled to heavy metal targets for efficient neutron production. They form the basis of large scale neutron scattering facilities, and are essential elements in accelerator-driven subcritical reactors. Demanding technology has been developed which is enabling the next generation of spallation neutron sources to reach even higher neutron fluxes. This technology sets the stage for future deployment in accelerator-driven systems and neutron sources for nuclear material irradiation.