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Full-Text Articles in Physics
First Observation Of P-Odd Γ Asymmetry In Polarized Neutron Capture On Hydrogen, D. Blyth, J. Fry, N. Fomin, R. Alarcon, L. Alonzi, E. Askanazi, S. Baeßler, S. Balascuta, L. Barrón-Palos, A. Barzilov, J. D. Bowman, N. Birge, J. R. Calarco, T. E. Chupp, V. Cianciolo, C. E. Coppola, Chrisopher B. Crawford, K. Craycraft, D. Evans, C. Fieseler, E. Frlež, I. Garishvili, M. T. W. Gericke, R. C. Gillis, K. B. Grammer, G. L. Greene, J. Hall, J. Hamblen, C. Hayes, E. B. Iverson, Md Latiful Kabir, Mark Mccrea, R. Milburn, F. Simmons, Aaron P. Sprow, E. Tang
First Observation Of P-Odd Γ Asymmetry In Polarized Neutron Capture On Hydrogen, D. Blyth, J. Fry, N. Fomin, R. Alarcon, L. Alonzi, E. Askanazi, S. Baeßler, S. Balascuta, L. Barrón-Palos, A. Barzilov, J. D. Bowman, N. Birge, J. R. Calarco, T. E. Chupp, V. Cianciolo, C. E. Coppola, Chrisopher B. Crawford, K. Craycraft, D. Evans, C. Fieseler, E. Frlež, I. Garishvili, M. T. W. Gericke, R. C. Gillis, K. B. Grammer, G. L. Greene, J. Hall, J. Hamblen, C. Hayes, E. B. Iverson, Md Latiful Kabir, Mark Mccrea, R. Milburn, F. Simmons, Aaron P. Sprow, E. Tang
Physics and Astronomy Faculty Publications
We report the first observation of the parity-violating gamma-ray asymmetry Anpγ in neutron-proton capture using polarized cold neutrons incident on a liquid parahydrogen target at the Spallation Neutron Source at Oak Ridge National Laboratory. Anpγ isolates the ΔI = 1, 3S1 → 3P1 component of the weak nucleon-nucleon interaction, which is dominated by pion exchange and can be directly related to a single coupling constant in either the DDH meson exchange model or pionless effective field theory. We measured Anpγ = [−3.0 ± 1.4(stat )± 0.2(syst)] × 10−8 …
First Direct Constraints On Fierz Interference In Free-Neutron Β Decay, K. P. Hickerson, X. Sun, Y. Bagdasarova, D. Bravo-Berguño, L. J. Broussard, M. A. -P. Brown, R. Carr, S. Currie, X. Ding, B. W. Filippone, A. García, P. Geltenbort, J. Hoagland, A. T. Holley, R. Hong, T. M. Ito, A. Knecht, C. -Y. Liu, J. L. Liu, M. Makela, R. R. Mammei, J. W. Martin, D. Melconian, M. P. Mendenhall, S. D. Moore, C. L. Morris, R. W. Pattie Jr., A. Pérez Galván, R. Picker, M. L. Pitt, Bradley R. Plaster
First Direct Constraints On Fierz Interference In Free-Neutron Β Decay, K. P. Hickerson, X. Sun, Y. Bagdasarova, D. Bravo-Berguño, L. J. Broussard, M. A. -P. Brown, R. Carr, S. Currie, X. Ding, B. W. Filippone, A. García, P. Geltenbort, J. Hoagland, A. T. Holley, R. Hong, T. M. Ito, A. Knecht, C. -Y. Liu, J. L. Liu, M. Makela, R. R. Mammei, J. W. Martin, D. Melconian, M. P. Mendenhall, S. D. Moore, C. L. Morris, R. W. Pattie Jr., A. Pérez Galván, R. Picker, M. L. Pitt, Bradley R. Plaster
Physics and Astronomy Faculty Publications
Precision measurements of free-neutron β decay have been used to precisely constrain our understanding of the weak interaction. However, the neutron Fierz interference term bn, which is particularly sensitive to beyond-standard-model tensor currents at the TeV scale, has thus far eluded measurement. Here we report the first direct constraints on this term, finding bn = 0.067 ± 0.005stat+0.090-0.061sys, consistent with the standard model. The uncertainty is dominated by absolute energy reconstruction and the linearity of the β spectrometer energy response.
Evolution Equations For Connected And Disconnected Sea Parton Distributions, Keh-Fei Liu
Evolution Equations For Connected And Disconnected Sea Parton Distributions, Keh-Fei Liu
Physics and Astronomy Faculty Publications
It has been revealed from the path-integral formulation of the hadronic tensor that there are connected sea and disconnected sea partons. The former is responsible for the Gottfried sum rule violation primarily and evolves the same way as the valence. Therefore, the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations can be extended to accommodate them separately. We discuss its consequences and implications vis-á-vis lattice calculations.