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arXiv · 1106.5334

The small x gluon and b\bar{b} production at the LHC

E. G. de Oliveira·A. D. Martin·M. G. Ryskin
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Abstract

We study open b\bar{b} production at large rapidity at the LHC in an attempt to pin down the gluon distribution at very low x. For the LHC energy of 7 TeV, at next-to-leading order (NLO), there is a large factorization scale uncertainty. We show that the uncertainty can be greatly reduced if events are selected in which the transverse momenta of the two B-mesons balance each other to some accuracy, that is |\vec p_{1T}+\vec p_{2T}| < k_0. This will fix the scale μ_F \simeq k_0, and will allow the LHCb experiment, in particular, to study the x-behaviour of gluon distribution down to x ~ 10^{-5}, at rather low scales, μ~ 2 GeV. We evaluate the expected cross sections using, for illustrative purposes, various recent sets of Parton Distribution Functions.

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E. G. de Oliveira, A. D. Martin, M. G. Ryskin. 2011-06-27. The small x gluon and b\bar{b} production at the LHC. https://doi.org/10.1140/epjc%2Fs10052-011-1727-x

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