Roles of ?(1232), N~*(1520), and N~*(1650) resonances in γp → π~0π~0p reaction within an effective Lagrangian approach

【摘要】 The roles of the ?(1232), N~*(1520), and N~*(1650) resonances in the γ p → π~0π~0p reaction near threshold is investigated within an effective Lagrangian approach. The differential cross sections of the γp → π~0π~0p reaction was calculated including contributions from the ?(1232), N~*(1520), and N~*(1650) intermediate states decaying into π~0p via the s-channel nucleon pole and t-channel ρ exchange. Current experimental measurements were well reproduced. The production of ?(1232) was mainly from the mechanism of the s-channel nucleon pole, while the N~*(1520) and N~*(1650) were produced from the mechanism of the t-channel ρ exchange. More experimental data on the γp → π~0π~0p reaction could be used to explore the properties of the low-lying excited baryon state.更多还原

【Abstract】 The roles of the ?(1232), N~*(1520), and N~*(1650) resonances in the γ p → π~0π~0p reaction near threshold is investigated within an effective Lagrangian approach. The differential cross sections of the γp → π~0π~0p reaction was calculated including contributions from the ?(1232), N~*(1520), and N~*(1650) intermediate states decaying into π~0p via the s-channel nucleon pole and t-channel ρ exchange. Current experimental measurements were well reproduced. The production of ?(1232) was mainly from the mechanism of the s-channel nucleon pole, while the N~*(1520) and N~*(1650) were produced from the mechanism of the t-channel ρ exchange. More experimental data on the γp → π~0π~0p reaction could be used to explore the properties of the low-lying excited baryon state.更多还原