Neutron Radiative Capture and Transmission Measurements of W and Zr Isotopes in the keV Region

Neutron capture and transmission measurements have been carried out upon ¹⁸²W, ¹⁸³W, ¹⁸⁴W, ¹⁸⁶W, ⁹⁰Zr, ⁹¹Zr, ⁹²Zr, and ⁹⁴Zr over the energy range from ∼150 eV to ≤100 keV at the Rensselaer Polytechnic Institute LINAC Laboratory. Many new resonances have been observed and many resonances, reported previously as singlets, have been resolved into doublets. Most of the resonances that previously eluded observation are assigned to p-wave neutrons. Pertinent resonance parameters have been extracted from the data, and the s-wave and the p-wave strength functions of tungsten and zirconium have been determined from these parameters. The values of the s-wave strength functions in units of 10⁻⁴ are: for ¹⁸²W, 2.60 ± 0.54; for ¹⁸³W, 2.41 ± 0.48 per spin state; for ¹⁸⁴W, 3.0 ± 0.6; for ¹⁸⁶W, 2.15 ± 0.46; for ⁹⁰Zr, 2.0 ± 1.4; for ⁹¹Zr, 1.2 ± 0.4 per spin state; for ⁹²Zr, 2.6 ± 1.5, and for ⁹⁴Zr, 1.0 ± 0.8. The p-wave strength functions in units of 10⁻⁴ are: for the even-even tungsten isotopes, ; for ⁹⁰Zr, 7 ± 4; for ⁹¹Zr, 3 ± 2 per spin state; for ⁹²Zr, 7 ± 5, and for ⁹⁴Zr, 4 ± 2.