Browsing by Author "Macklin, RL"

Now showing 1 - 6 of 6
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    keV neutron capture in zirconium-91
    (Australian Atomic Energy Commission., 1975-01) Allen, BJ; Musgrove, ARD; Macklin, RL
    The neutron capture cross section of 91Zr has been measured with high resolution (∆E/E ~ 0.2 per cent) between 3 and 30 keV. Values of the gгnгγ/г for 119 resonances in this energy range have been obtained. The average capture cross section is consistent with values of <гγs> = <гγp> = 200.
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    keV neutron resonance capture in barium-135
    (Australian Atomic Energy Commission, 1974-12) Musgrove, ARD; Allen, BJ; Macklin, RL
    The neutron capture cross section of 135Ba has been measured with high resolution at the Oak Ridge Linear Accelerator in the energy range 3 to 100 keV. From over ninety observed resonances in the 3 to 6 keV energy range, the average resonance parameters obtained were: <гγ> = 150 ± 20 meV; = 39.3 ± 4 eV and l0 4S = 0.8 ± 0.2. The quoted radiation width and p-wave strength function also have a normalisation error of ± 20 per cent. The method of separation of в- and p-wave populations by statistical methods is described.
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    Neutron capture by the chromium isotopes
    (Australian Atomic Energy Commission, 1977-01) Kenny, MJ; Allen, BJ; Musgrove, ARD; Macklin, RL; Halperin, J
    Capture cross sections of the chromium isotopes have been measured at neutron energies up to 350 keV using the capture cross section facility at the 40 m station of the Oak Ridge Electron Linear Accelerator. Parameters have been derived for 180 resonances. A moderate correlation [p(г0n,гγ) - 0.45] is observed between reduced neutron widths n y and radiative widths for s-wave resonances. Calculations of valence widths show that valence capture can only account for the correlated component of the observed radiative widths. An additional mechanism such as a 2p-lh doorway state must therefore be occurring to explain the uncorrelated component.
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    Non-statistical effects in the radioactive capture cross sections of the neodymium isotopes
    (Australian Atomic Energy Commission, 1977-01) Musgrove, ARD; Allen, BJ; Boldeman, JW; Macklin, RL
    The neutron capture cross sections of the stable neodymium isotopes have been measured with high energy resolution in the keV region at the 40 m station of ORELA. Average resonance parameters are extracted for s-wave resonances. Significant positive correlations are found between T0n and Tγ all isotopes. The magnitude of the observed correlation coefficient, particularly for 142Nd (p = 0.9), cannot be explained in terms of valence neutron capture and additional mechanisms are discussed. The average s-wave radiative widths for the odd-A isotopes are markedly greater than for the even-A isotopes, while the p-wave radiative width for 142Nd is considerably less than the s-wave width.
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    Resonance neutron capture in the isotopes of titanium
    (Australian Atomic Energy Commission, 1977-06) Allen, BJ; Boldeman, JW; Musgrove, ARD; Macklin, RL
    The neutron capture cross sections of 46,47,48,49,50Ti have been measured from 2.75 to 300 keV with ~0.2 per cent energy resolution. The reduced neutron and radiative widths of the s-wave resonances exhibit correlations which, with the exception of 47Ti, are consistent with the calculated magnitudes of the valence component, assuming that the radiative widths contain an additional uncorrelated part. In 47Ti, a significant correlation is observed for J=3- resonances, although the calculated valence component is small.
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    Valence neutron capture in iron 54Fe
    (Australian Atomic Energy Commission, 1977-02) Allen, BJ; Musgrove, ARD; Boldeman, JW; Macklin, RL
    The neutron capture cross section of S4Fe has been measured with 0.2 per cent energy resolution from 2.5 to 500 keV. A large and significant correlation is observed between the s-wave reduced neutron widths and the corresponding total radiative widths. The valence model readily accounts for this correlation as well as a large fraction of the s-wave radiative widths.