1974Physical Review ARequires access

Electron capture from He(1s2) by protons. III

Robert A. Mapleton, Richard W. Doherty, Paul E. Meehan

Open publisher page 8 citations

Abstract

The prior (i), post (f), and distorted wave (dw) forms of the first Born approximation, and a one-parameter approximate helium wave function, are used to calculate cross sections for electron capture from $\mathrm{He}(1{s}^{2})$ by protons. These cross sections are calculated for capture into $\mathrm{H}(3lm)$, $l=1, 2$; $\ensuremath{-}1\ensuremath{\le}m\ensuremath{\le}1$, for impact energies, $10\ensuremath{\le}E\ensuremath{\le}1000$ keV, leaving the residual ion ${\mathrm{He}}^{+}(1s)$. The associated polarizations $P$ are calculated for the axis of quantization of H parallel to the direction of incidence, and the apparent cross sections ${Q}_{A}=3Q{(3\ensuremath{-}P)}^{\ensuremath{-}1}$ are obtained from $P$ and the calculated cross sections $Q=\ensuremath{\Sigma}{m=\ensuremath{-}l}^{l}{Q}_{m}$. The $Q$ used to determine ${Q}_{A}$ are $Q(\mathrm{dw})$ and the arithmetic average of $Q(\mathrm{i})$ and $Q(\mathrm{f})$. Of these two sets, ${Q}_{A}(\mathrm{dw})$ predicts the measured ${Q}_{A}(3p)$ more successfully for $E<250$ keV, and the measured ${Q}_{A}(3d)$ better for $E<200$ keV. For larger values of $E$ both sets predict the measured values equally well. In the range $15\ensuremath{\le}E\ensuremath{\le}60$ keV, the effect of $P(\mathrm{dw})$ is more marked for capture into $\mathrm{H}(3p)$ than into $\mathrm{H}(3d)$.

About this research paper

What this paper is about

The prior (i), post (f), and distorted wave (dw) forms of the first Born approximation, and a one-parameter approximate helium wave function, are used to calculate cross sections for electron capture from $\mathrm{He}(1{s}^{2})$ by protons. These cross sections are calculated for capture into $\mathrm{H}(3lm)$, $l=1, 2$; $\ensuremath{-}1\ensuremath{\le}m\ensuremath{\le}1$, for impact energies, $10\ensuremath{\le}E\ensuremath{\le}1000$ keV, leaving the residual ion ${\mathrm{He}}^{+}(1s)$. The associated polarizations $P$ are calculated for the axis of quantization of H parallel to the direction of incidence, and the apparent cross sections ${Q}_{A}=3Q{(3\ensuremath{-}P)}^{\ensuremath{-}1}$ are obtained from $P$ and the calculated cross sections $Q=\ensuremath{\Sigma}{m=\ensuremath{-}l}^{l}{Q}_{m}$. The $Q$ used to determine ${Q}_{A}$ are $Q(\mathrm{dw})$ and the arithmetic average of $Q(\mathrm{i})$ and $Q(\mathrm{f})$. Of these two sets, ${Q}_{A}(\mathrm{dw})$ predicts the measured ${Q}_{A}(3p)$ more successfully for $E<250$ keV, and the measured ${Q}_{A}(3d)$ better for $E<200$ keV. For larger values of $E$ both sets predict the measured values equally well. In the range $15\ensuremath{\le}E\ensuremath{\le}60$ keV, the effect of $P(\mathrm{dw})$ is more marked for capture into $\mathrm{H}(3p)$ than into $\mathrm{H}(3d)$.

Why it matters

OpenAlex reports 8 citations for this work. Citation counts describe recorded attention and do not establish research quality.

Key contribution

A contribution statement is not available in the OpenAlex record.

Method / approach

Method details are not available in the OpenAlex metadata.

Main findings

Findings are not separately available in the OpenAlex metadata.

Limitations

Limitations are not available in the OpenAlex metadata.

Applications

Application details are not available in the OpenAlex metadata.

Available abstract

The prior (i), post (f), and distorted wave (dw) forms of the first Born approximation, and a one-parameter approximate helium wave function, are used to calculate cross sections for electron capture from $\mathrm{He}(1{s}^{2})$ by protons. These cross sections are calculated for capture into $\mathrm{H}(3lm)$, $l=1, 2$; $\ensuremath{-}1\ensuremath{\le}m\ensuremath{\le}1$, for impact energies, $10\ensuremath{\le}E\ensuremath{\le}1000$ keV, leaving the residual ion ${\mathrm{He}}^{+}(1s)$. The associated polarizations $P$ are calculated for the axis of quantization of H parallel to the direction of incidence, and the apparent cross sections ${Q}_{A}=3Q{(3\ensuremath{-}P)}^{\ensuremath{-}1}$ are obtained from $P$ and the calculated cross sections $Q=\ensuremath{\Sigma}{m=\ensuremath{-}l}^{l}{Q}_{m}$. The $Q$ used to determine ${Q}_{A}$ are $Q(\mathrm{dw})$ and the arithmetic average of $Q(\mathrm{i})$ and $Q(\mathrm{f})$. Of these two sets, ${Q}_{A}(\mathrm{dw})$ predicts the measured ${Q}_{A}(3p)$ more successfully for $E<250$ keV, and the measured ${Q}_{A}(3d)$ better for $E<200$ keV. For larger values of $E$ both sets predict the measured values equally well. In the range $15\ensuremath{\le}E\ensuremath{\le}60$ keV, the effect of $P(\mathrm{dw})$ is more marked for capture into $\mathrm{H}(3p)$ than into $\mathrm{H}(3d)$.

Key concepts: Physics, Electron capture, Atomic physics, Born approximation, Electron, Crystallography, Nuclear physics, Chemistry

Related papers

Back to paper searchBrowse research topicsOriginal source
Electron capture from He(1s2) by protons. III — Research Paper | ScholarLens