A variable-geometry beam-shaping assembly for accelerator-based BNCT

Although the beam shaping assemblies (BSAs) for reactor-based Boron Neutron Capture Therapy (BNCT) facilities are typically of a single design, the accelerator beams with the possibility to provide neutron spectrum to give characteristics which are optimum for different treatment sites and tumor depth generally may require a fine-tuning procedure which can be undertaken with variable-geometry BSA. In this study, a special geometry is proposed for use with a hybrid photoneutron source equipped with drill-chuck type head. Both the neutron spectrum and epithermal neutron flux can be treated by changing the BSA geometry

NE102A Plastic Scintillator Response to He-3 Ions

Plastic scintillators are widely used in detecting nuclear radiation due to their low construction cost, the ability to be produced in nearly any shape and size and relatively fast time response, among which NE102A (or its equivalents, BC400 and EJ-212) is one of the most famous and widely used scintillators in the focal plane of the particle magnetic spectrometers. In this study, the response of a large NE102A scintillator to He-3 ions was investigated in the energy range of 55-87 MeV. The experimental data were collected from the measurements carried out at the accelerator center of University of Groningen, the Netherlands (KVI-CART). The results of this research, acceptably consistent with previous published experimental data, confirmed that the response of the NE102A scintillator to He-3 ions with energies more than 10 MeV is approximately linear

Spectral modeling of scintillator for the NEMO-3 and SuperNEMO detectors

We have constructed a GEANT4-based detailed software model of photon transport in plastic scintillator blocks and have used it to study the NEMO-3 and SuperNEMO calorimeters employed in experiments designed to search for neutrinoless double beta decay. We compare our simulations to measurements using conversion electrons from a calibration source of $\rm ^{207}Bi$ and show that the agreement is improved if wavelength-dependent properties of the calorimeter are taken into account. In this article, we briefly describe our modeling approach and results of our studies.Comment: 16 pages, 10 figure

Systematic study on

Within the framework of the proximity formalism, we present a systematic study to analyze the effects of the $$\alpha$$-decay energy through the effective sharp radius parameter on the $$\alpha$$-decay half-lives of 227 nuclei in the range $$61 \le Z \le 99$$. Wentzel-Kramers-Brillouin (WKB) calculations with the proximity potential Zhang 2013 are carried out to obtain the theoretical values of the $$\alpha$$-decay half-lives. In this work, we introduce a new $$Q_{\alpha }$$-dependent (QD) form of the effective sharp radius which significantly reduces the standard deviation of estimated half-lives using the Zhang 2013 model in comparison with the corresponding experimental data in our selected mass range. We evaluate the validity of this simple formula using the Geiger-Nuttall (G-N) plots and semi-empirical formulas. The modified form of the Zhang 2013 model is also found to work well in $$\alpha$$-decay studies of superheavy nuclei (SHN) with $$Z=117-120$$. Our results reveal that the calculated half-lives for the use of new proposed form of the effective sharp radius in the proximity potential can reproduce the closed-shell effects at neutron magic number $$N=126$$ and $$N=184$$