0 Weak - Interaction Evidence for a Broad σ ( 500 - 600 ) Resonance
نویسندگان
چکیده
We explore how chiral-symmetry constraints on weak-interaction matrix elements suggest the existence of an intermediate-state σ in several different weak-interaction processes. Particular attention is directed toward recent evidence for a σ within three-body nonleptonic weak decays. The existence of a broad scalar-isoscalar ππ resonance near 500-600 MeV, the σ, has long been controversial. After having been absent for many years from the listings of the Particle Data Group (PDG) in the Reviews of Particle Physics [1], this resonance has reappeared under the name " f 0 (400 − 1200) or σ " (hereafter called σ(500 − 600)) after reanalysis by several groups [2] of the available data on the scalar nonet and ππ phase shifts. Today an increasing number of theoretical and experimental analyses point towards the existence of 1
منابع مشابه
ar X iv : h ep - p h / 00 05 10 6 v 1 1 1 M ay 2 00 0 Weak - Interaction Evidence for a Broad σ ( 500 - 600 ) Resonance
We explore how chiral-symmetry constraints on weak-interaction matrix elements suggest the existence of an intermediate-state σ in several different weak-interaction processes. Particular attention is directed toward recent evidence for a σ within three-body nonleptonic weak decays. The existence of a broad scalar-isoscalar ππ resonance near 500-600 MeV, the σ, has long been controversial. Afte...
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We explore how chiral-symmetry constraints on weak-interaction matrix elements point toward the existence of an intermediate-state σ in several different weak-interaction processes. Particular attention is directed toward recent evidence for a σ within three-body nonleptonic weak decays. PACS numbers: 11.30.Rd, 11.40.Ha, 14.40.Cs HIP-2000-22/TH The existence of a broad scalar-isoscalar ππ reson...
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The formalism of Dalitz-Plot analysis is reviewed in the preceeding note. Table 1 lists reported analyses of D mesons. In the following, we discuss a number of subjects of current interest: (1) D0 → K0 Sππ; (2) D → πππ: a σ(500) or f0(600); (3) D+ → K−π+π+: a κ(800)? (4) the f0(980), f0(1370) and f0(1500); (5) doubly Cabibbo-suppressed decays; and (6) CP violation. D0 → K0 Sππ: Several experime...
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