Importance of the N. delta. inelastic threshold for understanding low-energy NN amplitudes

Journal Article · Tue Jun 01 04:00:00 EDT 1976 · Phys. Rev., D; (United States)

DOI:https://doi.org/10.1103/PhysRevD.13.2944· OSTI ID:7326056

Kane, G L; Thomas, G H

The authors relate three interesting aspects of low-energy NN reaction: (1) The large value of ..delta..sigma/subt/ = sigma/subT/(arrow-down)- sigma/subt/(arrow-down) for pp scattering for P/sub LAB/ below 3 GeV/c; (2) the existence at low energies of large unnatural-parity t-channel amplitudes with nonpion quantum numbers; (3) the anomalous variation with energy of the slope and differential cross section at t =0 in np ..-->.. pn in the range P/sub LAB/ = 0.5--2 GeV/c. Based on the somewhat crude phase-shift analyses which exist above the single-pion inelastic threshold, it is argued that all three of the above aspects of NN reactions are the reflections of the dominant inelastic channel pp ..-->.. N..delta... The well-known possibility that the large amplitudes so generated are related to resonant behavior (in the /sup 1/D/sub 2/ partial wave of pp ..-->.. pp) is discussed. That some low-energy amplitudes are strongly affected by s-channel threshold effects demonstrates one cannot, in general, equate features of high-energy amplitudes with those of low-energy amplitudes whenever inelastic thresholds are important. (AIP)

• Research Organization: Physics Department, University of Michigan, Ann Arbor, Michigan 48104
• OSTI ID: 7326056
• Journal Information: Phys. Rev., D; (United States), Journal Name: Phys. Rev., D; (United States) Vol. 13:11; ISSN PRVDA
• Country of Publication: United States
• Language: English

Related Subjects

645207* -- High Energy Physics-- Particle Interactions & Properties-Theoretical-- Strong Interactions
Baryon No. Greater than 1-- (-1987)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AMPLITUDES
BARYON RESONANCES
BARYON-BARYON INTERACTIONS
BARYONS
BASIC INTERACTIONS
CHARGE-EXCHANGE INTERACTIONS
CROSS SECTIONS
D WAVES
DIFFERENTIAL CROSS SECTIONS
ELASTIC SCATTERING
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
GEV RANGE
GEV RANGE 01-10
HADRON-HADRON INTERACTIONS
HADRONS
HELICITY
INTERACTIONS
MEV RANGE
MEV RANGE 100-1000
N RESONANCES
NUCLEON-NUCLEON INTERACTIONS
NUCLEONS
PARTIAL WAVES
PARTICLE INTERACTIONS
PARTICLE PROPERTIES
PHASE SHIFT
PROTON-NEUTRON INTERACTIONS
PROTON-NUCLEON INTERACTIONS
PROTON-PROTON INTERACTIONS
RESONANCE PARTICLES
SCATTERING
SCATTERING AMPLITUDES
STRONG INTERACTIONS
T CHANNEL