Abstract
The NPDGamma experiment measures the parity-violating (PV) gamma asymmetry from polarized cold neutrons captured on protons at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). The (PV) neutron spin asymmetry A γ of photons from polarized cold neutron capture on protons is proportional to the ΔI=1 long range weak meson coupling \(h_{\pi }^{1}\) between nucleons in the hadronic weak interaction (HWI). Liquid para-hydrogen production data taking concluded in April 2014 and once the background aluminum asymmetry measurements are complete, the PV asymmetry A γ can be extracted. Preliminary results of the analysis of A γ are presented.
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This article is part of the Topical Collection on Proceedings of the 6th International Symposium on Symmetries in Subatomic Physics (SSP 2015), VicCanada, 8-12 June 2015
Edited by Michael Gericke and Gerald Gwinner
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Fry, J., Alarcon, R., Allen, R. et al. Status of the NPDGamma experiment. Hyperfine Interact 238, 11 (2017). https://doi.org/10.1007/s10751-016-1376-4
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DOI: https://doi.org/10.1007/s10751-016-1376-4
Keywords
- Nucleon-nucleon interactions
- Parity-violation
- Nuclear tests of fundamental symmetries
- Few nucleon systems