科研之友
微信
新浪微博
Facebook
分享链接
摘要
Quark and gluon jets are studied in three-jet events generated by Jetset 7.4 and Herwig 5.9 at root s = 91.2 GeV. The quark jets are identified by b-tag tracing, and the remaining jet is then defined as the gluon jet. A new physical variable, i.e. the cone-angle, which is able to describe the geometrical characteristic of the jet, is defined. It turns out that the cone-angle distribution of the gluon jet is wider than its mother quark jet, i.e. the gluon jet is "fatter". As the multiplicity increases, the cone-angle distribution of the quark jet has an upward-going trend, i.e. a positive correlation is present. The cone-angle of the gluon and quark jet versus their transverse momentum develop a valley. The mean cone-angles of both the gluon jet and the quark jet are negatively correlated with the transverse momentum for p(t) < 3 GeV/c, but are positively correlated for pt > 3 GeV/c. The mean cone-angles of the gluon and quark jets are well separated, showing that they can be utilized in the identification of the two kinds of jets.
- 出版日期2005-4
- 单位长江大学; 华中师范大学; 中国地质大学（北京）
