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11.
In the present paper the sensitivity V of plastic nuclear track detectors CR-39 to the space radiation, accelerated heavy ions in wide LET range and α-particles is studied. Different approaches for V evaluation are considered and compared. Main attention is given to the method that is appropriate for the measurement of short range heavy secondaries of space radiation. Finally, the experimental verification of the designed V function is carried out via simulation of the secondaries with low energy α-particles in the vicinity of the Bragg peak. 相似文献
12.
The photoproduction of K+ mesons from the nucleon provides important constraints on the nucleon excitation spectrum and at threshold energies challenges effective field theories based on chiral perturbation in the strange quark sector. Preliminary cross-section measurements for γ(P, K+)A are presented at an unprecedented beam energy resolution. The data was collected at the MAMI-C facility in Mainz using the Crystal Ball Detector. A new method of K+ detection was used in which the K+ is tagged from its weak decay products in the detector crystals. This technique has application with other calorimeters at present and future hadron facilities. 相似文献
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14.
Jean-Pierre Aubin Georges Haddad 《Journal of Mathematical Analysis and Applications》2002,275(2):676-692
Given a target contained in a constrained set and an impulse control system governing the evolutions of runs or executions, that are hybrids of continuous and discrete evolutions, this paper studies and provides several characterizations of the capture basin of the target viable in the constrained set. It is the subset of initial runs from which start at least one run viable in the constrained set until it reaches the target in finite time. It also provides algorithms and regulation rules governing the runs that reach the targets while obeying state constraints. 相似文献
15.
The problem of nonlinear optimization is encountered while fitting the observed response of certain radiation detectors. In
this paper the development of an optimizing technique based on quasi random search is described. The performance of this technique
is compared with other existing methods of gradient search and linear Taylor differential correction technique in the case
of fitting the photopeak responses of Nal(Tl) detectors. Our results are favourable especially when the observed data are
associated with poor statistics. 相似文献
16.
碘化钠NaI(Tl)单晶闪烁探测器的应用 总被引:1,自引:0,他引:1
碘化钠NaI(Tl)单晶闪烁探测器由射线探测器、计算机多道、高压电源及线性放大器、计算机多道脉冲幅度分析器等部分组成。当放射源发出的γ射线进入闪烁体时,γ光子即与闪烁体中的原子、分子及晶体系统发生相互作用(如光电效应,康普顿散射和电子对效应等)。 相似文献
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18.
Polyethylene converter silicon detectors have been developed as part of a dosimetry system for the application in neutron fields. Signals have been investigated which are mainly caused by reactions occurring when neutrons hit the PE converter or the silicon diode directly. In this work, neutron interactions in the components of a PE converter silicon sensor have been calculated to determine energy deposition distributions for neutron energies from 1.2 v MeV to 14.8 v MeV. Experiments in quasi-monoenergetic neutron fields have been performed. For the simulation of the neutron interactions with the detector layers, the GSF neutron interaction code NISD has been applied. The transport of ions has been calculated separately by means of the program TRIM. It has been shown that by the use of these concepts and models, a rather good agreement of measured and computed pulse height distributions can be obtained and, consequently, the response of converter type detectors to neutron radiation can be determined. 相似文献
19.
A precise operation of the position-sensing detectors (PSD) is exploited in this study. A position-sensing detector is modeled and the amplified output signal for this device as a result of input source current variation is studied. Beam displacement on such detectors is calculated and approximated and more accurate expressions for the generated signals are obtained. Linearity effect in output response of such a device is also investigated. The expansion coefficients for the signals are determined, which show the effect of the nonlinear terms. The first nonlinear coefficient is about 16.6% of the linear coefficient while the next terms are 2.5, 0.89, and 0.48% of the linear coefficient, respectively. For a position change of x=0.2 unit the linear term is 0.08, the third-order term −0.005328, and the fifth-order term is only about 0.000032, which is negligible. To see the operational result, using software simulates a PSD and the related circuit that provides the positional information. 相似文献
20.