Application of current-algebra techniques to soft-pion production by the weak neutral current: $S$ , $P$ , $T$ case

Journal Article · Mon Dec 01 04:00:00 EST 1975 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.12.3501· OSTI ID:4074925

Adler, Stephen L.; Colglazier, E. W.; Healy, J. B.; Karliner, Inga; Lieberman, Judy; Ng, Yee Jack; Tsao, Hung-Sheng

We develop the cross-section formulas needed to correlate information on neutral currents obtained from deep-inelastic neutrino scattering, neutrino-- proton elastic scattering, and neutral-current--induced soft-pion production, in the case of neutral currents with S, P, T spatial structure. (The necessary S, P, T current renormalization constants were estimated by us in a previous paper.) The pion-emission amplitude is obtained by current-algebra soft-pion techniques, with the effects of (3, 3)-resonance--excitation taken into account to leading nonvanishing order in the static approximation. We analyze recently reported Brookhaven National Laboratory results for neutral-current--induced soft-pion production under the simplifying assumption of a purely isoscalar S, P, T neutral current, while simultaneously imposing existing bounds on neutrino--proton elastic scattering and fitting existing data on neutral-current--induced deep- inelastic scattering. If all S, P, T renormalization constants are given their central quark-model values, the elastic-scattering and deep-inelastic restrictions constrain the pion-production cross section to be too low compared with experiment; if apparently reasonable deviations of the parameters from the quark-model values are permitted, satisfactory fits to all data are obtained with S, T, with P, T or with S, P, T mixtures. An isovector tensor or pseudoscalar neutral current is found to lead to a strong (3,3) peak in $pi$N invariant-mass plots, but an isovector scalar neutral current can be present without producing a visible (3,3) peak, even when ratios of the various $pi$N charge states produced by the neutral current are appreciably changed from the values which they have in the isoscalar-current case. Constructive T interference with S (or S and P) in $nu$ + N $Yields$ $nu$ + N + $pi$ and observation of unequal neutrino- and antineutrino-induced neutral-current cross sections are also indicated. (AIP)

• Research Organization: The Institute for Advanced Study, Princeton, New Jersey 08540
• Sponsoring Organization: USDOE
• NSA Number: NSA-33-021412
• OSTI ID: 4074925
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 11 Vol. 12; ISSN PRVDAQ; ISSN 0556-2821
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

*NEUTRINO-PROTON INTERACTIONS-- WEAK NEUTRAL CURRENTS
641103*
CURRENT ALGEBRA
DEEP INELASTIC SCATTERING N
DELTA-1236 RESONANCES
N64230* --Physics (High Energy)--Particle Interactions & Properties (Theoretical)--Weak
N64320 --Physics (High Energy)--Particle Invariance Principles & Symmetry--Applications (Electromagnetic & Weak)
NEUTRINO-NUCLEON INTERACTIONS-- NEUTRINOS-- NUCLEONS-- PARTICLE PRODUCTION-- PIONS
PSEUDOSCALARS
QUARK MODEL
RENORMALIZATION
SCALARS
TENSORS ELASTIC SCATTERING