Decay rates f1(1285) → ρ0π+π— and a1(1260) → ωπ+π— in the Nambu — Jona-Lusinio model
Семинары
Семинар «Физика адронов»
Дата и время: пятница, 25 мая 2018 г., в 11:00
Место: Конференц-зал им. Блохинцева (4-й этаж), Лаборатория теоретической физики им. Н.Н. Боголюбова
Тема семинара: «Decay rates f1(1285) → ρ0π+π— and a1(1260) → ωπ+π— in the Nambu — Jona-Lusinio model»
Авторы: А.А. Осипов, А.А. Пивоваров, М.К. Волков
Докладчик: А.А. Осипов
Аннотация:
The anomalous decays f1(1285) → ρ0π+π— violating natural parity for vectors and axial-vectors are studied in the framework of the Nambu — Jona-Lasinio model. We consider the Lagrangian with U(2)L x U(2)R chiral symmetric four quark interactions. The theory is bosonized and corresponding effective mason verticles are obtained in the leading order of 1/Nc and derivative expansions. The uncertainties related with the surface terms of anomalous quark triangle diagrams are fixed by the corresponding symmetry requirements. We make a numerical estimate of the decay widths Г(f1(1285) —> ρ0π+π—=2.78 MeV and Г(a1(1260) → ωπ+π—)=87 keV. Our result on the f1(1285) —> ρ0π+π— decay rate is in a good agreement with experiment. It is shown that a strong suppression of the a1(1260) → ωππ decay is a direct consequence of destructive interference between box and triangle anomalies.