Improved Numerical Generalization of the Bethe-Weizsäcker Mass Formula for Prediction the Isotope Nuclear Mass, the Mass Excess Including of Artificial Elements 119 and 120
Mavrodiev Strachimir Chterev,
Vol Alexander
Issue:
Volume 4, Issue 2, June 2019
Pages:
11-22
Received:
5 June 2019
Accepted:
15 July 2019
Published:
26 July 2019
Abstract: George Gamow’s liquid drop model of the nucleus can account for most of the terms in the formula and gives rough estimates for the values of the coefficients. Its semi-numerical equation was first formulated in 1935 by Weizsäcker and in 1936 Bethe [1, 2], and although refinements have been made to the coefficients over the years, the structure of the formula remains the same today. Their formula gives a good approximation for atomic masses and several other effects, but does not explain the appearance of magic numbers of protons and neutrons, and the extra binding-energy and measure of stability that are associated with these numbers of nucleons. Mavrodiev and Deliyergiyev [3] formalized the nuclear mass problem in the inverse problem framework. This approach allowed them to infer the underlying model parameters from experimental observation, rather than to predict the observations from the model parameters. They formulated the inverse problem for the numerically generalized semi-empirical mass formula of Bethe and von Weizsäcker going step-by-step through the AME2012 [4] nuclear database. The resulting parameterization described the measured nuclear masses of 2564 isotopes with a maximal deviation of less than 2.6 MeV, starting from the number of protons and number of neutrons equal to 1. The unknown functions in the generalized mass formula was discovered in a step-by-step way using the modified procedure realized in the algorithms developed by Aleksandrov [5-7] to solve nonlinear systems of equations via the Gauss-Newton method. In the presented herein article we describe a further development of the obtained by [3] formula by including additional factors,- magic numbers of protons, neutrons and electrons. This inclusion is based the well-known experimental data on the chemically induced polarization of nuclei and the effect of such this polarization on the rate of isotope decay. It allowed taking into account resonant interaction of the spins of nuclei and electron shells. As a result the maximal deviation from the measured nuclear masses of less than 1.9 MeV was reached. This improvement allowed prediction of the nuclear characteristics of the artificial elements 119 and 120.
Abstract: George Gamow’s liquid drop model of the nucleus can account for most of the terms in the formula and gives rough estimates for the values of the coefficients. Its semi-numerical equation was first formulated in 1935 by Weizsäcker and in 1936 Bethe [1, 2], and although refinements have been made to the coefficients over the years, the structure of t...
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Improvement in Optical Properties of Nuclear Track Detector
Doaa Hassan Shabaan,
Tayseer Ibrahim AL-Naggar
Issue:
Volume 4, Issue 2, June 2019
Pages:
23-26
Received:
3 July 2019
Accepted:
31 July 2019
Published:
2 September 2019
Abstract: The purpose of this work was obtaining information about the interaction of γ- ray with CR-39 track detector by using the UV-Vis spectrometry and FTIR which can be used in concerning sensor for gamma irradiation. CR-39 samples irradiated by radioactive source Co-60 at different doses are (0, 100, 200, 300, 400, and 500 kGy). The UV-Vis spectroscopy show transitions electronic in the visible region from ground state to excited state, by increasing gamma doses, and the absorbance spectrum for all samples take the same behavior with slightly shift. This shift due to decrease in the optical band gap energy Eg. The FTIR spectra show for all samples there are increases in the intensity of the characteristic peaks with increasing gamma ray, at 3234, 2367 and 1817 cm-1, this increase may be related to more oxidation process that, in turn was produced on the polymer chains by increase gamma doses, and the number of peaks at 1817, 2367, 2645 and 3234 cm-1 is belong to carbonate group C=O stretching vibration, O=C=O asymmetric by stretching, C-H Stretching, H2O free stretching vibration, respectively. By increase gamma ray did not observed changes in the CR-39 groups but observed change in the intensities of peaks, then CR-39 detector can be used properly in the field of radiation dosimetery.
Abstract: The purpose of this work was obtaining information about the interaction of γ- ray with CR-39 track detector by using the UV-Vis spectrometry and FTIR which can be used in concerning sensor for gamma irradiation. CR-39 samples irradiated by radioactive source Co-60 at different doses are (0, 100, 200, 300, 400, and 500 kGy). The UV-Vis spectroscopy...
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