Associated Production of Z Boson and a Pair of New Quarks at LHC  

作　　者：杨硕 

机构地区：[1]Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, P.O. Box 2735

出　　处：《Communications in Theoretical Physics》2010年第6期1133-1136,共4页理论物理通讯（英文版）

基　　金：Supported in part by the National Science Foundation of China under Grant Nos.90503002 and 10821504;by the National Basic Research Program of China under Grant No.2010CB833000

摘　　要：The associated production of Z boson and a pair of new quarks at the Large Hadron Collider （LHC） is studied. The cross sections for both sequential fermions and vector-like fermions are presented. It is found that for sequential fermions the cross sections can reach 1 - 10^2 /b for heavy quark mass mQ from 1000 GeV to 200 GeV. For vector-like quarks, the cross sections are suppressed by mixing parameter sin OL. Focusing on process pp → b＇b＇, we investigate the possibility of detecting the 6l 4- 2j signal. For a b＇ with light mass and a large branching ratio of b＇ → bZ, it is found that only several signal events （ parton level ） can be produced with 1000 fb^-1 integrated luminosity. Although the signal events are rare, all the final states are produced centrally and multi lepton final states are clear at hadron collider, which could be easily detected.

关 键 词：physics beyond the standard model fourth generation LHC 

分 类 号：O572.33[理学—粒子物理与原子核物理]