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My talk is concerned with a review, not necessarily of the latest theoretical developments, but rather of an old idea which has contributed to recent theoretical activities. By soft pion processes I mean processes in which law energy pions are emitted or absorbed or scattered, just as we use the word soft photon in a similar context. Speaking more quantitatively, we may call a pion soft if its energy is small compared to a natural scale in the reation. This scale is determined by the particular dynamics of pion interaction, and one may roughly say that a pion is soft if its energy is small compared to the energies of the other individual particles that participate in the reaction. It is important to note at this point that pion is by far the lightest member of all the hadrons, and much of the success of the soft pion formulas depends on this fact.
Publication Date:
OSTI Identifier:
Report Number(s):
COO--264-421; CONF-680102--2; EFI--68-11
DOE Contract Number:
Resource Type:
Technical Report
Resource Relation:
Other Information: From Meeting of the American Physical Society, Chicago, Ill. UNCL. Orig. Receipt Date: 31-DEC-68
Research Org:
Enrico Fermi Institute and Department of Physics, University of Chicago, Chicago, IL
Sponsoring Org:
US Atomic Energy Commission (AEC)
Country of Publication:
United States
N34260* --Physics (High Energy)--Particle Interactions & Properties (Theoretical)--Strong (Baryon No. = 1); CHIRALITY; EMISSION; FIELD THEORY; INTERACTIONS; PARTICLE MODELS; PIONS; QUANTUM MECHANICS; SCATTERING MESONS ($pi$)/interactions of soft, review of, (T); MESONS ($pi$)/production of soft, review of