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Parity violating electron nucleus scattering is a clean and powerful tool for measuring the spatial distributions of neutrons in nuclei with unprecedented accuracy. Parity violation arises from the interference of electromagnetic and weak…

Nuclear Theory · Physics 2014-11-18 C. J. Horowitz , S. J. Pollock , P. A. Souder , R. Michaels

The capability of the NLC in the $\gamma e$ collider mode to probe the CP-conserving $\gamma WW$ and $\gamma ZZ$ anomalous couplings through the use of the polarization asymmetry is examined. When combined with other measurements, very…

High Energy Physics - Phenomenology · Physics 2011-04-15 Thomas G. Rizzo

Two-pion exchange parity-violating nucleon-nucleon interactions from recent effective field theories and earlier fully covariant approaches are investigated. The potentials are compared with the idea to obtain better insight on the role of…

Nuclear Theory · Physics 2008-11-26 B. Desplanques , C. H. Hyun , S. Ando , C. -P. Liu

A permanent electric dipole moment of fundamental spin-1/2 particles violates both parity (P) and time re- versal (T) symmetry, and hence, also charge-parity (CP) symmetry since there is no sign of CPT-violation. The search for a neutron…

We use QCD sum rules to obtain the weak parity-violating pion-nucleon coupling constant $f_{\pi NN}$. We find that $f_{\pi NN}\approx 2\times 10^{-8}$, about an order of magnitude smaller than the ``best estimates'' based on quark models.…

Nuclear Theory · Physics 2014-11-18 E. M. Henley , W-Y. P. Hwang , L. S. Kisslinger

We use QCD sum rules to obtain the weak parity-violating pion-nucleon coupling constant $f_{\pi NN}$. We find that $f_{\pi NN}\approx 3\times 10^{-8}$, up to an order of magnitude smaller than the ``best estimates" based on quark models.…

Nuclear Theory · Physics 2016-09-08 E. M. Henley , W-Y. P. Hwang , L. S. Kisslinger

The search for CP violating forces between nucleons in the so-called axion window of force ranges lam between 2x10^-5 m and 0.02 m is interesting because only little experimental information is available there. Axion-like particles would…

We describe a modular apparatus for use in parity-violation measurements in epithermal neutron-nucleus resonances with high instantaneous neutron fluxes at the Manuel Lujan Jr.\ Neutron Scattering Center at Los Alamos National Laboratory.…

Significant progress has been made to experimentally determine a complete set of the parity-violating (PV) weak-interaction amplitudes between nucleons. In this paper we describe the design, construction and operation of the n$^3$He…

From the recent measurement of parity nonconservation (PNC) in the Cs atom we have extracted the constant of the nuclear spin dependent electron-nucleon PNC interaction, $\kappa = 0.442 (63)$; the anapole moment constant, $\kappa_a = 0.364…

Nuclear Theory · Physics 2008-11-26 V. V. Flambaum , D. W. Murray

By looking at the parity-nonconserving (PNC) asymmetries at different energies in $\vec{p} p$ scattering, it is in principle possible to determine the PNC $\rho NN$ and $\omega NN$ couplings of a single-meson-exchange model of the PNC $NN$…

Nuclear Theory · Physics 2009-11-11 C. -P. Liu , C. H. Hyun , B. Desplanques

A precise measurement of the neutron decay $\beta$-asymmetry $A_0$ has been carried out using polarized ultracold neutrons (UCN) from the pulsed spallation UCN source at the Los Alamos Neutron Science Center (LANSCE). Combining data…

There have been suggestions to measure atomic parity nonconservation (PNC) along an isotopic chain, by taking ratios of observables in order to cancel complicated atomic structure effects. Precise atomic PNC measurements could make a…

Nuclear Theory · Physics 2008-11-26 S. J. Pollock , E. N. Fortson , L. Wilets

Electron interactions with the nuclear-spin-dependent (NSD) parity non-conserving (PNC) anapole moment are strongly enhanced within heteronuclear diatomic molecules. A novel, low-energy optical rotation experiment is being proposed with the…

Precision measurements of parity non-conserving (PNC) interactions in atoms, molecules and ions can lead to the discovery of new physics beyond the standard model and understanding of weak-force induced interactions in the nucleus. In this…

Atomic Physics · Physics 2018-08-02 J. Choi , R. T. Sutherland , George Toh , A. Damitz , D. S. Elliott

We investigate the possibility of measuring the pion dispersion relation in nuclear matter through the anomalous coupling in the reaction \gamma - \gamma' \pi_0. It is shown that this reaction permits the study of pionic modes for…

Nuclear Theory · Physics 2008-11-26 Alexander Volya , Kevin Haglin , Scott Pratt , Vladimir Dmitriev

The PADME experiment will search for the invisible decay of Dark Photons produced in interactions of positron from the DA$\Phi$NE Linac on a target. The collaboration aims at reaching a sensitivity of $\sim10^{-3}$ on the coupling constant…

Instrumentation and Detectors · Physics 2016-08-02 G. Piperno

Novel experimental techniques are required to make the next big leap in neutron electric dipole moment experimental sensitivity, both in terms of statistics and systematic error control. The nEDM experiment at the Spallation Neutron Source…

We examine the capability of the NLC in the $\gamma e$ collider mode to probe the CP-conserving $\gamma WW$ and $\gamma ZZ$ anomalous couplings through the use of the polarization asymmetry. When combined with other measurements, very…

High Energy Physics - Phenomenology · Physics 2007-05-23 Thomas G. Rizzo

Weak interactions are expected to induce a parity violating pion-nucleon coupling, h_{\pi NN}^{(1)}. This coupling should be measurable in a proposed experiment to study the parity violating asymmetry A_\gamma in the process \vec n + p \to…

Nuclear Theory · Physics 2009-10-31 David B. Kaplan , Martin J. Savage , Roxanne P. Springer , Mark B. Wise