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arXiv · 1802.00064

Impact of low-$x$ resummation on QCD analysis of HERA data

xFitter Developers' team·:·Hamed Abdolmaleki·Valerio Bertone·Daniel Britzger·Stefano Camarda·Amanda Cooper-Sarkar·Francesco Giuli·Alexander Glazov·Aleksander Kusina·Agnieszka Luszczak·Fred Olness·Andrey Sapronov·Pavel Shvydkin·Katarzyna Wichmann·Oleksandr Zenaiev·Marco Bonvini
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Abstract

Fits to the final combined HERA deep-inelastic scattering cross-section data within the conventional DGLAP framework of QCD have shown some tension at low $x$ and low $Q^2$. A resolution of this tension incorporating $\ln(1/x)$-resummation terms into the HERAPDF fits is investigated using the xFitter program. The kinematic region where this resummation is important is delineated. Such high-energy resummation not only gives a better description of the data, particularly of the longitudinal structure function $F_L$, it also results in a gluon PDF which is steeply rising at low $x$ for low scales, $Q^2 \simeq 2.5$ GeV$^2$, contrary to the fixed-order NLO and NNLO gluon PDF.

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xFitter Developers' team, :, Hamed Abdolmaleki, Valerio Bertone, Daniel Britzger, Stefano Camarda, Amanda Cooper-Sarkar, Francesco Giuli, Alexander Glazov, Aleksander Kusina, Agnieszka Luszczak, Fred Olness, Andrey Sapronov, Pavel Shvydkin, Katarzyna Wichmann, Oleksandr Zenaiev, Marco Bonvini. 2018-01-31. Impact of low-$x$ resummation on QCD analysis of HERA data. https://arxiv.org/abs/1802.00064

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