Application of current algebra to soft-pion production induced by the weak neutral current: Second-class V, A case

Journal Article · Mon Dec 01 04:00:00 EST 1975 · Phys. Rev., D, v. 12, no. 11, pp. 3522-3532

DOI:https://doi.org/10.1103/PhysRevD.12.3522· OSTI ID:4070562

Adler, S L; Dashen, R F; Healy, J B; Karliner, I; Lieberman, J; Ng, Y J; Tsao, H

We apply current-algebra techniques to study neutrino--proton elastic scattering and neutral-current--induced soft-pion production in the case of second-class vector and axial-vector currents. (Such currents are CP-violating if the final and incident neutrinos are identical, but can be CP-conserving if the final and incident neutrinos are different particles.) The second-class currents are constructed phenomenologically from meson fields and the usual first- class V, A quark currents. The matrix elements of the second-class currents between one-nucleon states are estimated by inserting a complete set of intermediate states and saturating the sum with one-nucleon states. In this way the second-class matrix elements are expressed in terms of the experimentally measured renormalization constant of the first-class V, A currents and the pion-- nucleon coupling constants. Using standard soft-pion techniques, we analyze recently reported Brookhaven National Laboratory results for neutral-current-- induced soft-pion production under the simplifying assumption of a purely isoscalar second-class V, A neutral current. We find in this case that a second- class V--A current is consistent with the reported results. Some qualitative features of second-class neutral currents are equal cross sections for $nu$p and nu-barp elastic scattering, with only the axial-vector current contributing, and very small $nu$p and nu-barp elastic cross sections at energies of order 50 MeV, which are relevant for possible neutrino experiments of the Los Alamos Meson Physics Facility. (AIP)

• Research Organization: Institute for Advanced Study, Princeton, New Jersey 08540
• Sponsoring Organization: USDOE
• NSA Number: NSA-33-021409
• OSTI ID: 4070562
• Journal Information: Phys. Rev., D, v. 12, no. 11, pp. 3522-3532, Journal Name: Phys. Rev., D, v. 12, no. 11, pp. 3522-3532; ISSN PRVDA
• Country of Publication: United States
• Language: English

Related Subjects

*NEUTRINO-PROTON INTERACTIONS-- WEAK NEUTRAL CURRENTS
641103*
ANTINEUTRINO-PROTON INTERACTIONS-- ELASTIC SCATTERING
AXIAL-VECTOR CURRENTS
COUPLING CONSTANTS
CURRENT ALGEBRA
N64230* --Physics (High Energy)--Particle Interactions & Properties (Theoretical)--Weak
N64320 --Physics (High Energy)--Particle Invariance Principles & Symmetry--Applications (Electromagnetic & Weak)
QUARK MODEL
VECTOR CURRENTS PARTICLE PRODUCTION-- PIONS