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arXiv · 0909.5327

The aT distribution of the Z boson at hadron colliders

Andrea Banfi·Mrinal Dasgupta·Rosa Maria Duran Delgado
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Abstract

We provide the first theoretical study of a novel variable, $a_T$, proposed in Ref.[1] as a more accurate probe of the region of low transverse momentum $p_T$, for the $Z$ boson $p_T$ distribution at hadron colliders. The $a_T$ is the component of $p_T$ transverse to a suitably defined axis. Our study involves resummation of large logarithms in $a_T$ up to the next-to--leading logarithmic accuracy and we compare the results to those for the well-known $p_T$ distribution, identifying important physical differences between the two cases. We also test our resummed result at the two-loop level by comparing its expansion to order $\alpha_s^2$ with the corresponding fixed-order results and find agreement with our expectations.

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Andrea Banfi, Mrinal Dasgupta, Rosa Maria Duran Delgado. 2009-09-29. The aT distribution of the Z boson at hadron colliders. https://doi.org/10.1088/1126-6708/2009/12/022

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