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arXiv 1104.2849hep-ph
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U(3)CHPT中介子-介子散射的共振

Resonances from meson-meson scattering in U(3) CHPT

Zhi-Hui Guo, J. A. Oller

摘要:

本文首次采用具有显式共振态的U(3)\otimes U(3)手征微扰理论对介子-介子散射振幅进行了完整的单圈计算。采用基于N/D方法的非微扰方法,从微扰计算中将分波归一化。一旦实验数据以令人满意的方式再现,我们然后研究共振性质,如极点位置,相应的残基和它们的N_C行为。在文献中首次考虑了在大N_C时,η_1成为手征极限下的第九个Goldstone玻色子。在这个方案中,所研究的矢量共振ρ(770)、K^*(892)和K_(1020)遵循N_C轨迹,与它们的标准\bar{q} q解释一致。标量f_0(1370)、a_0(1450)和K^*(1430)对于大N_C也有一个\bar{q} q极点位置轨迹,它们都趋向于1.4 GeV附近标量共振的裸八位组。在1GeV附近,f_0(980)渐近地趋向于单重标量共振的裸极点位置.σ、κ和a_0(980)标量共振态具有非常不同的N_C行为。特别详细地分析了σ共振的情况。

英文摘要:

In this work, the complete one loop calculation of meson-meson scattering amplitudes within U(3)\otimes U(3) chiral perturbation theory with explicit resonance states is carried out for the first time. Partial waves are unitarized from the perturbative calculation employing a non-perturbative approach based on the N/D method. Once experimental data are reproduced in a satisfactory way we then study the resonance properties, such as the pole positions, corresponding residues and their N_C behaviors. The resulting N_C dependence is the first one in the literature that takes into account the fact that the η_1 becomes the ninth Goldstone boson in the chiral limit for large N_C. Within this scheme the vector resonances studied, ρ(770), K^*(892) and ϕ(1020), follow an N_C trajectory in agreement with their standard \bar{q}q interpretation. The scalars f_0(1370), a_0(1450) and K^*(1430) also have for large N_C a \bar{q}q pole position trajectory and all of them tend to a bare octet of scalar resonances around 1.4 GeV. The f_0(980) tends asymptotically to the bare pole position of a singlet scalar resonance around 1 GeV. The σ, κand a_0(980) scalar resonances have a very different N_C behavior. The case of the σresonance is analyzed with special detail.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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