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arXiv · hep-ph/9603281

The Subjet Multiplicity in Quark and Gluon Jets

Michael H. Seymour
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Abstract

We calculate the mean number of subjets in quark and gluon jets in the final state of e^+e^- annihilation. Since `quark' and `gluon' jets are scheme-dependent objects, we stress the importance of using the same definition as in experimental analyses. We define the jets using the k_perp algorithm at a coarse scale y_1, and the subjets using a finer scale y_0, 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 alpha_s, and resums leading and next-to-leading logarithmic terms in the ratio y_1/y_0 to all orders in alpha_s.

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Michael H. Seymour. 1996-03-12. The Subjet Multiplicity in Quark and Gluon Jets. https://doi.org/10.1016/0370-2693(96)00399-1

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