The Subjet Multiplicity in Quark and Gluon Jets
نویسنده
چکیده
We calculate the mean number of subjets in quark and gluon jets in the final state of ee annihilation. Since “quark” and “gluon” jets are schemedependent objects, we stress the importance of using the same definition as in experimental analyses. We define the jets using the k⊥ algorithm at a coarse scale y1, and the subjets using a finer scale y0, in the same algorithm. Gluon jets are anti-tagged by the presence of heavy quarks in both other jets. Our result is exact to leading order in αs, and resums leading and next-to-leading logarithmic terms in the ratio y1/y0 to all orders in αs. CERN–TH/95–225 March 1996
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تاریخ انتشار 1996