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Measurements of parity-violating longitudinal analyzing powers (normalized asymmetries) in polarized proton-proton scattering provide a unique window on the interplay between the weak and strong interactions between and within hadrons.…

Nuclear Experiment · Physics 2015-06-26 W. T. H. van Oers , for E497 collaboration

We study relationship between the physical quantities that characterize pion-nucleon and nucleon-nucleon interaction on the basis of the fact that nuclear forces in the nucleon-nucleon system at low energies are mainly determined by the…

Nuclear Theory · Physics 2016-04-12 V. A. Babenko , N. M. Petrov

We present the first application of statistical spectroscopy to study the root-mean-square value of the parity nonconserving (PNC) interaction matrix element M determined experimentally by scattering longitudinally polarized neutrons from…

Nuclear Theory · Physics 2009-10-31 S. Tomsovic , Mikkel B. Johnson , A. Hayes , J. D. Bowman

We discuss experiments aimed at measurements of atomic parity nonconservation (PNC) effects in the 1S0-3D1 transition (408 nm) in atomic Ytterbium (Z=70). According to theoretical predictions, the PNC-induced E1 amplitude of this transition…

Atomic Physics · Physics 2007-09-27 K. Tsigutkin , J. E. Stalnaker , D. Budker , S. J. Freedman , V. V. Yashchuk

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 2007-05-23 C. J. Horowitz

We investigate the parity-violating analyzing power in neutron capture on the proton at thermal energies in the framework of chiral effective field theory. By combining this analysis with a previous analysis of parity violation in…

Nuclear Theory · Physics 2015-06-15 J. de Vries , N. Li , Ulf-G. Meißner , A. Nogga , E. Epelbaum , N. Kaiser

We discuss a self-consistent method to calculate the properties of cold asymmetric nuclear matter which is dressed with isoscalar scalar pion condensates. The nucleon-nucleon interaction is mediated by these pion pairs, omega- and rho-…

Nuclear Theory · Physics 2007-12-03 S. Sarangi , P. K. Panda , S. K. Sahu , L. Maharana

We present a detailed report of a measurement of the neutron $\beta$-asymmetry parameter $A_0$, the parity-violating angular correlation between the neutron spin and the decay electron momentum, performed with polarized ultracold neutrons…

The weak interaction does not conserve parity and therefore induces energy shifts in chiral enantiomers that should in principle be detectable in molecular spectra. Unfortunately, the magnitude of the expected shifts are small and in…

For decades the primary experimental goal in studies of hadronic parity nonconservation (PNC) has been the isolation of the isovector weak nucleon-nucleon interaction, expected to be dominated by long-range pion exchange and enhanced by the…

Nuclear Theory · Physics 2017-10-11 Susan Gardner , W. C. Haxton , Barry R. Holstein

The parity-violating Lagrangian of the weak nucleon-nucleon ($NN$) interaction in the pionless effective field theory (EFT($//!/!/!/pi$)) approach contains five independent unknown low-energy coupling constants (LECs). The photon asymmetry…

Nuclear Theory · Physics 2014-10-21 M. Moeini Arani , S. Bayegan

Several new proton-proton parity violation experiments are presently either being performed or are being prepared for execution in the near future. Similarly, a new measurement of the parity-violating gamma-ray asymmetry in polarized…

High Energy Physics - Phenomenology · Physics 2009-10-31 Willem T. H. van Oers

We report a new limit on a possible short range spin-dependent interaction from the precise measurement of the ratio of Larmor precession frequencies of stored ultracold neutrons and $^{199}$Hg atoms confined in the same volume. The…

Precision experiments at low energies probing weak interaction are a very promising and complementary tool for investigating the structure of the electro-weak sector of the standard model, and for searching for new phenomena revealing signs…

High Energy Physics - Experiment · Physics 2010-02-25 Stephan Paul

We have measured both yields of neutron-proton and neutron-neutron pairs emitted from the non-mesonic weak decay process of 5_Lambda-He and 12_Lambda-C hypernuclei produced via the (pi^+,K^+) reaction for the first time. We observed clean…

We consider the two-nucleon weak interaction with a pionless effective field theory. Dibaryon fields are introduced to facilitate calculations and ensure precision in the initial and final state propagators. Weak interactions are accounted…

Nuclear Theory · Physics 2010-05-25 J. W. Shin , S. Ando , C. H. Hyun

Nuclear spin-dependent parity violation (NSD-PV) effects in atoms and molecules arise from $Z^0$ boson exchange between electrons and the nucleus, and from the magnetic interaction between electrons and the parity-violating nuclear anapole…

Atomic Physics · Physics 2018-04-06 Emine Altuntas , Jeffrey Ammon , Sidney B. Cahn , David DeMille

We study the coupled pion-nucleon system (negative parity, isospin 1/2) based on a lattice QCD simulation for nf=2 mass degenerate light quarks. Both, standard 3-quarks baryon operators as well as meson-baryon (4+1)-quark operators are…

High Energy Physics - Lattice · Physics 2013-05-20 C. B. Lang , V. Verduci

The parity-violating nucleon-nucleon (NN) potential is considered up to next-to-next-to leading order in heavy-baryon chiral perturbation theory. We include one-pion exchange at leading order and the two-pion exchange and two-nucleon…

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