The absolute yield, angular distribution and resonance widths of the 6.13, 6.92 and 7.12 MeV photons from the 340.5 keV resonance of the 19F(p,αγ)16O reaction

https://doi.org/10.1016/0168-9002(91)90204-4Get rights and content

Abstract

Although the low lying resonances in the 19F(p,αγ)16O reaction have been studied by many investigators in the past, only a few absolute determinations of the gamma-ray yield and branching ratios have been made. This is somewhat surprising in view of the widespread use of this reaction for the quantitative microanalysis of fluorine concentration profiles in the near surface regions of materials and for the calibration of gamma-ray detectors. In this work we report an absolute measurement of the yield, angular distribution and resonance widths of the 6.13, 6.92 and 7.12 MeV photons from the 340.5 keV resonance of the 19F(p,αγ)16O reaction.

Photons were produced by bombarding a semithick target of CaF2 with protons from the Harwell 6 MV Van de Graaff accelerator. A 113 cm3 HPGe spectrometer, with an energy resolution of 6.8 keV at 6129 keV, was used as the photon detector. This detector had previously been calibrated absolutely using a combination of radionuclide and thermal neutron capture gamma-ray sources at the neutron facility Badger, adjacent to the Harwell reactor DIDO. Measurements were made at seven angles in the range 0° – 150° permitting both differential and integral cross-sections to be derived. Geometrical correction factors were calculated using the Monte Carlo code EGS-4. A value for the reaction width was determined from the excitation curve.

With conventional notation the principal results are as follows: γ1 : γ2 : γ3 = 0.9701:0.0033:0.0266; ΓCM = (2.08±0.13) keV; and Y(γ1) = (8.72±0.37)×104 6129 keV γμC−1as.

References (9)

  • F. Ajzenberg-Selove

    Nucl. Phys.

    (1987)
  • S. Croft et al.

    Nucl. Instr. and Meth.

    (1991)
  • S. Croft

    Nucl. Instr. and Meth.

    (1989)
  • J.F. Janni

    Atomic Data and Nuclear Data Tables

    (1982)
There are more references available in the full text version of this article.

Cited by (27)

  • α-particle induced yield of 6.13 MeV γ-rays in carbon

    2021, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
  • Comments on extracting the resonance strength parameter from yield data

    2015, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
  • Thick target photon yields and angular distributions for the <sup>19</sup>F(p,αγ)<sup>16</sup>O source reaction at incident proton energies between 1.5 and 4.0 MeV

    2000, Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
  • Observation of uranium photo-fission by <sup>16</sup>N decay gamma rays from water activated by D-T fusion neutrons

    2000, Fusion Engineering and Design
    Citation Excerpt :

    In both instances the gamma rays follow the prompt radiative decay of excited levels in 16O. Some physical features of the 19F(p, α–γ)16O reaction, such as individual resonance parameters and both thick and thin target gamma-ray yields as a function of incident proton energy, have been studied and reported in the literature ([11–14]). This process has been exploited in developing a micro-analysis technique for the quantitative determination and depth profiling of fluorine in the surface region of various substrates (e.g. Refs. [12] and [14]).

View all citing articles on Scopus
View full text