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Parity Nonconservation In 106pd And 108pd Neutron Resonances, Bret E. Crawford, J D. Bowman, P P J. Delheij, T Haseyama, J N. Knudsen, L Y. Lowie, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, H Postma, N R. Roberson, S J. Seestrom, E I. Sharapov, Sharon L. Stephenson, V W. Yuan

Physics and Astronomy Faculty Publications

Parity nonconservation (PNC) has been studied in the neutron p-wave resonances of ¹⁰⁶Pd and ¹⁰⁸Pd in the energy range of 20 to 2000 eV. Longitudinal asymmetries in p-wave capture cross sections are measured using longitudinally polarized neutrons incident on ∼20-g metal-powder targets at LANSCE. A CsI γ-ray detector array measures capture cross section asymmetries as a function of neutron energy which is determined by the neutron time-of-flight method. A total of 21 p-wave resonances in ¹⁰⁶Pd and 21 p-wave resonances in ¹⁰⁸Pd were studied. One statistically significant PNC effect was observed in¹⁰⁶Pd, and no …

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Neutron Resonance Spectroscopy Of 103rh From 30 Ev To 2 Kev, D A. Smith, J D. Bowman, Bret E. Crawford, C A. Grossmann, T Haseyama, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, N R. Roberson, S J. Seestrom, E I. Sharapov, Sharon L. Stephenson, V W. Yuan

Physics and Astronomy Faculty Publications

Neutron resonances in ¹⁰³Rh have been measured for neutron energies from 30 to 2000 eV using the time-of-flight method and the (n,γ) reaction. The rhodium resonance spectroscopy is essential for the analysis of parity violation measurements recently performed on neutron resonances in ¹⁰³Rh. Neutron scattering and radiative widths were determined, and orbital angular momentum assignments made with a Bayesian analysis. The s-wave and p-wave strength functions and average level spacings were determined.

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Parity Violation In Neutron Resonances Of 103rh, D A. Smith, J D. Bowman, Bret E. Crawford, C A. Grossmann, T Haseyama, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, N R. Roberson, S J. Seestrom, E I. Sharapov, Sharon L. Stephenson, V W. Yuan

Physics and Astronomy Faculty Publications

Parity nonconservation (PNC) was studied in p-wave neutron resonances of ¹⁰³Rh in the neutron energy range 30 to 490 eV. The helicity dependence of the neutron total cross section of rhodium was determined by capture measurements with the time-of-flight method at the Manuel Lujan Neutron Scattering Center at the Los Alamos National Laboratory. A total of 32 p-wave resonances were studied and statistically significant longitudinal asymmetries were observed for resonances at E_n=44.5, 110.8, 321.6, and 432.9 eV. A statistical analysis treating the PNC matrix elements as random variables yields a weak spreading widthΓ_w=(1.42_-0.59^{+1.21 …}

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Neutron Resonance Spectroscopy Of 117sn From1 Ev To 1.5 Kev, D A. Smith, J D. Bowman, Bret E. Crawford, C A. Grossmann, T Haseyama, Mikkel B. Johnson, A Masaike, Y Matsuda, G E. Mitchell, V A. Nazarenko, S I. Penttila, N R. Roberson, S J. Seestrom, E I. Sharapov, L M. Smotritsky, Sharon L. Stephenson, V W. Yuan

Physics and Astronomy Faculty Publications

Parity violation has been studied recently for neutron resonances in ¹¹⁷Sn. The neutron resonance spectroscopy is essential for the analysis of the parity violation data. We have measured neutron resonances in ¹¹⁷Sn for neutron energies from 1 to 1500 eV using the time-of-flight method and the (n,γ) reaction. The sample was enriched to 87.6% ¹¹⁷Sn. Neutron scattering and radiative widths were determined, and orbital angular momentum assignments were made with a Bayesian analysis. The s-wave and p-wave strength functions and average level spacings were determined.

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Parity Nonconservation In Neutron Resonances In 133cs, E I. Sharapov, J D. Bowman, Bret E. Crawford, P P J. Delheij, T Haseyama, J N. Knudsen, L Y. Lowie, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, H Postma, N R. Roberson, S J. Seestrom, Sharon L. Stephenson, Y-F Yen, V W. Yuan

Physics and Astronomy Faculty Publications

Spatial parity nonconservation (PNC) has been studied in the compound-nuclear states of ¹³⁴Cs by measuring the helicity dependence of the neutron total cross section. Transmission measurements on a thick ¹³³Cs target were performed by the time-of-flight method at the Manuel Lujan Neutron Scattering Center with a longitudinally polarized neutron beam in the energy range from 5 to 400 eV. A total of 28 new p-wave resonances were found, their neutron widths determined, and the PNC longitudinal asymmetries of the resonance cross sections measured. The value obtained for the root-mean-square PNC element M=(0.06_-0.02^+0.25) meV in ^{133 …}

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Parity Violation In Neutron Resonances In 107,109ag, L Y. Lowie, J D. Bowman, J Corvi, Bret E. Crawford, P P J. Delheij, C M. Frankle, M Iinuma, J N. Knudsen, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, H Postma, N R. Roberson, S J. Seestrom, E I. Sharapov, H M. Shimizu

Physics and Astronomy Faculty Publications

Parity nonconservation (PNC) was studied in p-wave resonances in Ag by measuring the helicity dependence of the neutron total cross section. Transmission measurements on natural Ag were performed in the energy range 32 to 422 eV with the time-of-flight method at the Manuel Lujan Neutron Scattering Center at Los Alamos National Laboratory. A total of 15 p-wave neutron resonances were studied in ¹⁰⁷Ag and ninep-wave resonances in ¹⁰⁹Ag. Statistically significant asymmetries were observed for eight resonances in ¹⁰⁷Ag and for four resonances in¹⁰⁹Ag. An analysis treating the PNC matrix elements as random variables yields a …

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Search For Parity Violation In 93nb Neutron Resonances, E I. Sharapov, J D. Bowman, Bret E. Crawford, P P J. Delheij, C M. Frankle, K Fukuda, M Iinuma, J N. Knudsen, J Lokitz, L Y. Lowie, A Masaike, Y Matsuda, Y Matsuda, G E. Mitchell, S I. Penttila, H Postma, N R. Roberson, S J. Seestrom, H M. Shimizu, Sharon L. Stephenson, Y-F Yen, V W. Yuan

Physics and Astronomy Faculty Publications

A new search has been performed for parity violation in the compound nuclear states of ⁹⁴Nb by measuring the helicity dependence of the neutron total cross section. Transmission measurements on a thick niobium target were performed by the time-of-flight method at the Manuel Lujan Neutron Scattering Center with a longitudinally polarized neutron beam in the energy range 32 to 1000 eV. A total of 18 p-wave resonances in ⁹³Nb were studied with none exhibiting a statistically significant parity-violating longitudinal asymmetry. An upper limit of 1.0×10^-7 eV (95% confidence level) was obtained for the weak spreading widthΓ_{w …}

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Parity Nonconservation In 106pd And 108pd Neutron Resonances, Bret E. Crawford, J D. Bowman, P P J. Delheij, T Haseyama, J N. Knudsen, L Y. Lowie, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, H Postma, N R. Roberson, S J. Seestrom, E I. Sharapov, Sharon L. Stephenson, V W. Yuan

Physics and Astronomy Faculty Publications

Neutron Resonance Spectroscopy Of 103rh From 30 Ev To 2 Kev, D A. Smith, J D. Bowman, Bret E. Crawford, C A. Grossmann, T Haseyama, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, N R. Roberson, S J. Seestrom, E I. Sharapov, Sharon L. Stephenson, V W. Yuan

Physics and Astronomy Faculty Publications

Parity Violation In Neutron Resonances Of 103rh, D A. Smith, J D. Bowman, Bret E. Crawford, C A. Grossmann, T Haseyama, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, N R. Roberson, S J. Seestrom, E I. Sharapov, Sharon L. Stephenson, V W. Yuan

Physics and Astronomy Faculty Publications

Physics and Astronomy Faculty Publications

Parity Nonconservation In Neutron Resonances In 133cs, E I. Sharapov, J D. Bowman, Bret E. Crawford, P P J. Delheij, T Haseyama, J N. Knudsen, L Y. Lowie, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, H Postma, N R. Roberson, S J. Seestrom, Sharon L. Stephenson, Y-F Yen, V W. Yuan

Physics and Astronomy Faculty Publications

Parity Violation In Neutron Resonances In 107,109ag, L Y. Lowie, J D. Bowman, J Corvi, Bret E. Crawford, P P J. Delheij, C M. Frankle, M Iinuma, J N. Knudsen, A Masaike, Y Matsuda, G E. Mitchell, S I. Penttila, H Postma, N R. Roberson, S J. Seestrom, E I. Sharapov, H M. Shimizu

Physics and Astronomy Faculty Publications

Physics and Astronomy Faculty Publications