ETC模型与Zbb顶角

ETC Model and the Zbb Vertex

本文讨论了ＥＴＣ（ｅｘｔｅｎｄｔｅｃｈｎｉｃｏｌｏｒ）模型的规范玻色子的交换对Ｚｂ顶角的修正。具体计算表明“旁路”ＥＴＣ玻色子交换压低Ｚ→ｂｂ过程的宽度，而对角ＥＴＣ玻色子增加此宽度．二者总的修正在ＮＴＣ＝２时，增加Ｚ→ｂｂ宽度，这与最近的实验相符合．

We reconsider the non-oblique corrections to the Zbb vertex from the ETC boson exchange.We find that the sideways ETC boson exchange decreases the Zbb width while the diagonal ETCboson exchange increases it.For NTC= 2, the correction to the Zbb branching ratio is consisteat with the recent measurements.