Xiaohui Liu, Sonny Mantry, Frank Petriello
Signatures of new physics beyond the Standard Model are often characterized by large missing transverse energy ($\not E_T$) produced in association with multiple jets. The dominant Standard Model background to such processes comes from gauge-boson production in association with jets. A standard search strategy involves looking for an excess in the $m_{eff}$ distribution, where $m_{eff}= \not E_T +\sum_{J} p^T_J$ and $p^T_J$ denotes the transverse momentum of the $J$-th jet. The region of large $m_{eff}$ is dominated by jet production near threshold, giving rise to large Sudakov logarithms that can change the magnitude and shape of the $m_{eff}$ distribution. We present an effective theory framework for the resummation of such threshold logarithms. We perform an analysis for exclusive jet production using the N-jettiness global event shape, which allows theoretical control to also be maintained over large logarithms induced by vetoing additional jets. As a first step, we give explicit numerical results with next-to-leading-log (NLL) resummation for $pp \to \gamma + 2$ jets in the large $m_{eff}$ region.
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http://arxiv.org/abs/1205.4465
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