,Finite Size Vertex Correction to the Strong Decay of ηc and χc States and a Determination of αs(mc)

• 作 者: 平荣刚 姜焕清 邹冰松
• 机 构: Instit ut e of High Energy Physics, Chinese Academy of Sciences, P.O. Box 918, Beijing 100039“,”CCAS
• 出 处: 中国物理快报（英文版）
• 发表日期: 2002年2期

We calculate the correction to the two-gluon decay width due to the finite extension of the vertex function. We obtain the corrected factor to the zero-range vertex γ=1.32,γ=1.45,γ=1.26 forηc,χc0,andχc2,respectively. With the decay width Г(ηc → 2g) we extract the value αs(mc) = 0.28 ± 0.05 which agrees with that calculated from the same correction to the process Г( J/ψ → 3g). This correction to the process Г(ηc → 2g) is not as large as that to the process Г(J/ψ → 3g).