2014 | 2013 | 2012 | 2011 | 2010 | 2009 | 2008 | 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 | 1999 | 1998 | 1997 | 1996 | 1995 | 1994 | 1993 | 1992 | 1991 | 1990 | 1989 | 1988 | 1987 | 1986 | 1985 | 1984 | 1983 | 1982 | 1981 | 1980 | 1979 | 1978 | 1977 | 1976 | 1975 | 1974 | 1973 | 1972 | 1971 | 1970 | 1969 | 1968 | 1967 | 1966 | 1965 | 1964 | 1963 | 1962 | 1961 | 500 | 76 | 0
Low-energy theorem for γ→3π: surface terms against π-a1-mixing
Authors: A. A. Osipov, M. Khalifa, B. Hiller
Ref.: Phys. Rev. D101 no.3, 034012, 034012 (2020)
Abstract: We reconsider the contribution due to πa1 mixing to the anomalous γ→π+π0π- amplitude from the standpoint of the low-energy theorem Fπ=efπ2F3π, which relates the electromagnetic form factor Fπ0→γγ=Fπ with the form factor Fγ→π+π0π-=F3π both taken at vanishing momenta of mesons. Our approach is based on a recently proposed covariant diagonalization of πa1 mixing within a standard effective QCD-inspired meson Lagrangian obtained in the framework of the Nambu-Jona-Lasinio model. We show that the two surface terms appearing in the calculation of the anomalous triangle quark diagrams or AVV- and AAA-type (A, axial-vector; V, vector) amplitudes are uniquely fixed by this theorem. As a result, both form factors Fπ and F3π are not affected by the πa1 mixing, but the concept of vector meson dominance fails for γ→π+π0π-.
