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arXiv · hep-ph/0107001

Invariant Operators in Collinear Effective Theory

Christian W. Bauer·Iain W. Stewart
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Abstract

We consider processes which produce final state hadrons whose energy is much greater than their mass. In this limit interactions involving collinear fermions and gluons are constrained by a symmetry, and we give a general set of rules for constructing leading and subleading invariant operators. Wilson coefficients C(mu,P) are functions of a label operator P, and do not commute with collinear fields. The symmetry is used to reproduce a two-loop result for factorization in B -> D pi in a simple way.

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Christian W. Bauer, Iain W. Stewart. 2001-08-29. Invariant Operators in Collinear Effective Theory. https://doi.org/10.1016/s0370-2693(01)00902-9

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