Analysis of parity violating effects in complex nuclei

doi:10.1016/0370-2693(79)91216-4

Physics Letters B

Volume 84, Issue 4, 16 July 1979, Pages 363-367

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Abstract

We present an analysis of parity violating effects in complex nuclei in terms of two strengths of a nucleon-nucleus weak interaction. We show that, considering the theoretical uncertainties, the two strengths provide a consistent description of parity violating processes. The values of the strengths determined in the analysis are not inconsistent with the Weinberg- Salam model.

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Cited by (20)

Parity-non-conservation in nuclear forces at low energy: Phenomenology and questions
1998, Physics Report
The information available from the analysis of parity-non-conserving (pnc) effects in nuclear systems at low energy is considered. While five pieces of information corresponding to the five transitions between S and P nucleon–nucleon states should be at least determined, only three are presently more or less known. They are the strength of the pnc proton–nucleus and neutron–nucleus forces and that of the proton–proton force. Although it is not complete, this knowledge already provides a valuable discussion when it is compared to theoretical expectations. The discussion concerns the strength of the pnc πNN coupling constant, which determines the long-range part of pnc isovector forces, and the contribution of the pnc proton–proton force to the pnc proton–nucleus force. Both are too low in comparison with current expectations. Several issues to overcome these difficulties, that appeared with the advent of more accurate measurements of pnc effects in ¹⁸F and proton–proton scattering, are examined. They include an update of earlier estimates of the pnc πNN coupling constant, the role of collective effects in nuclei and new contributions to the pnc NN force, yet undetermined. Experiments, which may provide the missing information, are discussed.
Parity non-conservation in the pp system at low energy: Critical remarks about direct quark approaches
1995, Nuclear Physics, Section A
Several papers dealing with predictions for the parity-non-conserving longitudinal asymmetry in pp scattering at low energy, using either a quark-model approach or the concept of parity admixture of vector mesons, are reviewed. About 10 papers which are concerned with the determination of the sign are discussed here. It is shown that they predict a sign for the asymmetry which is likely to be incorrect and, in any case, in contradiction with the standard theoretical understanding of the sign actually determined by experiment. The relationship of these approaches with that based on the old factorization approximation is emphasized. In this order, many details are given, and obviously special attention is given to the sign prediction (conventions, definitions, phases, etc.).
Is the standard, parity-non-conserving, nucleon-nucleus interaction a surface one?
1995, Nuclear Physics, Section A
Claims that the standard single-particle, parity-non-conserving, nucleon-nucleus interaction, $V_{pnc} = ct · 1 2 {σ · p, ϱ(r)}$ , is a surface one are considered. It is shown that examination of integrands entering some quantity involving V_pnc leads to quite puzzling results. These are further supported by a similar examination for a term [ $σ · p, ϱ(r)$ ] which is odd under time-reversal, but has a priori a well-defined surface character. Alternative approaches to determine whether V_pnc is a surface or volume interaction are developed, based on using wave functions as test functions. From these approaches, the volume character of V_pnc is unambiguous.
Parity non-conservation at the peak of p-resonances in low-energy neutron-nucleus scattering
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Analysis of parity violating effects in complex nuclei

Abstract

Nucl. Phys.

Nucl. Phys.

Phys. Lett.

Phys. Lett.

Phys. Lett.

Sov. J. Nucl. Phys.

Nucl. Phys.

Phys. Rev.

BNL preprint-24468

Phys. Lett.

Nucl. Phys.

J. Phys.

J. Phys.