Effects of Flavour-Dependent qq Annihilation on the Mixing Angle of the Isoscalar Octet--Singlet and Schwinger’s Nonet Mass Formula
LI De-Min1, YU Hong1,2, SHEN Qi-Xing1,2
1Institute of High Energy Physics, Chinese Academy of
Sciences, Beijing 100039
2Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080
Effects of Flavour-Dependent qq Annihilation on the Mixing Angle of the Isoscalar Octet--Singlet and Schwinger’s Nonet Mass Formula
LI De-Min1;YU Hong1,2;SHEN Qi-Xing1,2
1Institute of High Energy Physics, Chinese Academy of
Sciences, Beijing 100039
2Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080
Abstract： By incorporating the flavour-dependent quark--antiquark annihilation amplitude into the mass-squared matrix describing the mixing of the isoscalar states of a meson nonet, the new version of Schwinger's nonet mass formula, which holds with a high accuracy for the 0-+, 1--, 2++, 2-+ and 3-- nonets, is derived and the mixing angle of the isoscalar octet--singlet for these nonets is obtained. In particular, the mixing angle of the isoscalar octet--singlet for the pseudoscalar nonet is determined to take the value of -12.92°, which is in agreement with the value range from -13° to -17° deduced from a rather exhaustive and up-to-date analysis of data. It is also pointed out that the omission of the flavour-dependent qq annihilation effect might be a factor resulting in the invalidity of Schwinger’s original nonet mass formula for the pseudoscalar nonet.
LI De-Min;YU Hong;SHEN Qi-Xing;. Effects of Flavour-Dependent qq Annihilation on the Mixing Angle of the Isoscalar Octet--Singlet and Schwinger’s Nonet Mass Formula
[J]. 中国物理快报, 2001, 18(2): 184-186.
LI De-Min, YU Hong, SHEN Qi-Xing,. Effects of Flavour-Dependent qq Annihilation on the Mixing Angle of the Isoscalar Octet--Singlet and Schwinger’s Nonet Mass Formula
. Chin. Phys. Lett., 2001, 18(2): 184-186.
2001, Vol. 18 
