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arXiv · 1704.00162

MMHT PDFs: updates and outlook

L. A. Harland-Lang·A. D. Martin·R. Nathvani·R. S. Thorne
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Abstract

We present the latest results of studies within the MMHT PDF framework. We discuss the impact of the most recent ATLAS 7 TeV jet data, demonstrating that while a good fit can be achieved for individual jet rapidity bins, it is not possible to achieve a good description of the data when all bins are fitted. We examine the role that the experimental correlated systematic uncertainties play in this, and demonstrate that by simply decorrelating no more than two sources of error between rapidity bins a remarkably improved description of the data can be achieved. We then study the impact of NNLO corrections, showing that a mild decrease in the fit quality is produced. We also present the results of including new LHC $W$, $Z$, $W+c$ and $t\overline{t}$ data on the MMHT14 PDF set, showing that a marked decrease in the $s+\overline{s}$ uncertainty is in particular achieved. Finally, some discussion of the latest work towards the inclusion of the photon PDF within the MMHT framework is presented.

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L. A. Harland-Lang, A. D. Martin, R. Nathvani, R. S. Thorne. 2017-04-01. MMHT PDFs: updates and outlook. https://doi.org/10.5506/aphyspolb.48.1011

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