Interaction parameters of protons in Aluminum and Iron

The interactions parameters(including ,stopping power with orbital electrons, continues slowing down ranges approximation and square of screening angle)for slow protons(10-500)MeV in aluminum and iron elements were calculated by adopting empirical equations through using Visual Basic Studio program 2016. the present study indicates that the calculated parameters show a linearity with the atomic number (Z) and the proton incident energy of the absorber the comparison with the available pervious experimental work gives a good agreement http://dx.doi.org/10.25130/tjps.24.2019.115

Advances in Spectral Distribution Assessment of Laser Accelerated Protons using Multilayer CR-39 Detectors

We show that a spectral distribution of laser-accelerated protons can be extracted by analyzing the proton track diameters observed on the front side of a second CR-39 detector arranged in a stack. The correspondence between the proton track diameter and the incident energy on the second detector is established by knowing that protons with energies only higher than 10.5 MeV can fully deposit their energy in the second CR-39 detector. The correlation between the laser-accelerated proton track diameters observed on the front side of the second CR-39 detector and the proton incident energy on the detector stack is also presented. By calculating the proton number stopped in the CR-39 stack, we find out that its dependence on the proton energy in the 1–15 MeV range presents some discontinuities at energies higher than 9 MeV. Thus, we build a calibration curve of the track diameter as a function of the proton incident energy within the 1–9 MeV range, and we infer the associated analytical function as the calculations performed indicate best results for proton spectra within the 1–9 MeV range. The calibration curve is used as a tool to ascertain the pits identified on the surfaces of both CR-39 detectors to proton tracks. The proton tracks spatial distribution analyzed by optical and atomic force microscopy is correlated with the peculiarity of the used targets.

Research on Nuclear Heat Deposition Behavior in the Spallation Target of an Accelerator Driven Subcritical System

The power density distribution behavior of the ADS spallation target, which is a key factor in the thermal-hydraulic and mechanical design of the high-power ADS target, was investigated under different proton incident energy. A Chinese ADS conceptual design of spallation target was proposed in this paper. The deposition heat in the spallation target was calculated by MCNPX code. From the results, it was found that the Bragg peak phenomenon weakens as the proton source incident energy increases. Large Bragg peak was observed for proton incident energy below 500MeV, however for the proton source energy above 900MeV, Bragg peak phenomena was not obvious. Analysis on the nuclear reactions behavior and ionization process induced by source proton in the target was carried out to address this issue. Meanwhile, the results show that the proton leakage rate from the target, which is an important factor in proton radiation shielding, greatly depends on the proton range (penetration depth) under different incident energy. In order to stop or keep the protons in the target, the minimum axial length (in the incoming particles direction) of the target at a given proton source incident energy should be determined according to the corresponding proton range. The results of this paper will be useful to guide the design of spallation target of a reference ADS.