Analyticity and the N-c counting rule of S matrix poles

作者：Xiao, Z. G.^*; Zheng, H. Q.

来源：Modern Physics Letters A, 2007, 22(1): 55-63.

DOI：10.1142/S0217732307020713

By studying pi pi scattering amplitudes in the large-N-c limit, we clarify the N-c dependence of the S matrix pole position. It is demonstrated that analyticity and the N(c)c ounting rule exclude the existence of S-matrix poles with M,Gamma similar to(1). Especially the properties of sigma and f(0) (980) with respect to the 1/N-c expansion are discussed.We point out that in general tetra-quark resonances do not exist.

• 出版日期2007-1-10
• 单位北京大学