Ratio of the <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">He</mi></mrow><mprescripts></mprescripts><mrow></mrow><mrow><mn>4</mn></mrow><mrow></mrow><mrow></mrow></mmultiscripts></mrow><mo>(</mo><mi>γ</mi><mo>,</mo><mi> </mi><mi>p</mi><mo>)</mo></math></span> and <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi mathvariant="normal">He</mi></mrow><mprescripts></mprescripts><mrow></mrow><mrow><mn>4</mn></mrow><mrow></mrow><mrow></mrow></mmultiscripts></mrow><mo>(</mo><mi>γ</mi><mo>,</mo><mi> </mi><mi>n</mi><mo>)</mo></math></span> Cross Sections

W. R. Dodge; J. J. Murphy, II

doi:10.1103/PhysRevLett.28.839

Ratio of the ${}^{4}{He} (γ, p)$ and ${}^{4}{He} (γ, n)$ Cross Sections

W. R. Dodge and J. J. Murphy, II

Phys. Rev. Lett. 28, 839 – Published 27 March 1972

Abstract

The ${}^{4}{He} (γ, p) {}^{3}H$ and ${}^{4}{He} (γ, n) {}^{3}{He}$ cross sections have been determined with a magnetic spectrometer in the energy interval of 30.0 to 51.8 MeV. We find that the average value of $\frac{σ (γ, p)}{σ (γ, n)}$ is 1.03±0.04 in the above energy interval. The ${}^{4}{He} (γ, p)$ cross section decreases from 1.52±0.13 mb at 31.7 MeV to 0.36±0.03 mb at 51.8 MeV.