[en] The total absolute cross sections for the production of 109 and 197 keV gamma rays, from the reaction F(p,p'γ)F, have been measured from 0.5 to 4.3 MeV, with an uncertainty of less than 8%. From these cross sections, detection sensitivities of fluorine-distributed uniformly in different matrices, with atomic numbers 6, 20, 42, 60, 79 and 92-have been calculated for different incident proton energies. (author)

[en] A new light nuclear reaction model has been developed and the double-differential measurements of 1p shell nuclei have been analyzed successfully. Now, the application of this model is expanded to ¹⁹F of the 2s-1d shell nucleus. The double-differential cross section of total outgoing neutron for n+¹⁹F reactions at E_n = 14.2 MeV has been calculated and analyzed, which agrees fairly well with the experimental measurements. In this paper, the contributions from different reaction channels to the double-differential cross sections have been analyzed in detail. The calculations indicate that this light nuclear reaction model is also able to be used for the 2s-1d shell nucleus so long as the related level scheme could be provided sufficiently.

No abstract available

[en] The radiation defects and damage in N-type GaP irradiated by 85 MeV ¹⁹F ions at fluences of 2.4 x 10¹⁵/cm² and 2.2 x 10¹⁶/cm² as a function of annealing temperature from 300 K to 1023 K were investigated by positron annihilation lifetime technique. Monovacancies were created in the irradiated N-type GaP, and the concentration of monovacancies was proportional to the irradiation fluence. Defects more complicated than di-vacancies in the high fluence irradiated GaP and di-vacancies in low fluence irradiated GaP were observed during annealing process, respectively. The complete annealing temperature of the defects for low fluence irradiated GaP was 250 K lower than that for high fluence irradiated GaP

No abstract available

[en] A re-examination of the ¹⁹(n,γ)²⁰F reaction has been conducted in which several factors were selected for optimization. These included sample purity, high statistical precision and hence sensitivity, sufficient energy precision and resolution to permit confident application of the Ritz combinational method, and efficiency calibration to test intensity balance in a meaningful way. The results obtained, besides increasing level-energy precision, revealed the likely existence of a new level and failed to agree with some aspects of earlier studies. The degree with which direct capture plays a role in this reaction was also explored and found to account for 35-50% of the 9 mb capture cross section. The neutron separation energy was found to be 6601.36 ± 0.05 keV, based upon the mass scale. A new level, forming a doublet with that at 3587 keV, was inferred to be at 3590 keV

No abstract available

[en] Published in summary form only

[en] Fission product yield studies in the reaction of 99.2 MeV ¹⁹F with ²⁰⁹Bi have been carried out for the first time using gamma-ray spectrometry. The cross sections for the production of fission products have been determined. The yield distribution of fission products was found to be symmetric and broad with FWHM around 22 mass units and peak near mass 111. The average number of neutrons emitted per fission has been found to be around 6.7. The comparison of the fission products yield distribution of ²⁰⁹Bi using projectiles like ⁴He, ¹²C, ¹⁶O, and ¹⁹F have shown that the mass of symmetric peak increases as the mass of the compound nucleus increases. The high fission yield around mass 112 has been attributed to the presence of deformed neutron shells. The total fission cross section and width of the mass distribution have been found to be low in case of ¹⁶O induced fission as compared to the ⁴He, ¹²C, and ¹⁹F induced fission of ²⁰⁹Bi. (author)

[en] Specific advantages with Particle Induced X-Ray Emission are: its 1) multielemental capability, especially when combined with nuclear techniques for lighter elements, 32) speed, 3)low detection limits for small samples and 4) accuracy. To make full use of these advantages, analytical parameters have to be chosen optimally and the facility to be carefully designed. This paper describes an experimental facility constructed to permit continous development work to optimize the analytical conditions and to allow the gradual implementation of automatic control. Emphasis is also put on the simultaneous use of proton induced gamma rays from fluorine. The features and the performance of the set-up including its accuracy, precision and experimental detection limits are reported. (Authors)