B-meson production in the Parton Reggeization Approach at Tevatron and the LHC

TL;DR

The paper addresses inclusive B-meson production in high-energy hadron collisions within the Parton Reggeization Approach (PRA). It develops a LO PRA framework with Reggeized gluons in the initial state, unintegrated gluon distributions (KMR), and universal B-meson fragmentation functions extracted from e+e- data. The authors find good agreement with central-rapidity data from Tevatron and LHC for large p_T without free parameters, offering an alternative to NLO CPM approaches; however forward-rapidity LHCb measurements are not reproduced, highlighting limitations of PRA at large x and motivating future work on NLO corrections and mass effects. They also provide predictions for 14 TeV LHC energies.

Abstract

We study the inclusive hadroproduction of $B^0$, $B^+$, and $B_s^0$ mesons at leading order in the parton Reggeization approach using the universal fragmentation functions extracted from the combined $e^+e^-$ annihilation data from CERN LEP1 and SLAC SLC colliders. We have described $B$-meson transverse momentum distributions measured in the central region of rapidity by the CDF Collaboration at Fermilab Tevatron and CMS Collaboration at LHC within uncertainties and without free parameters, applying Kimber-Martin-Ryskin unintegrated gluon distribution function in a proton. The forward $B$-meson production ($2.0<y<4.5$) measured by the LHCb Collaboration also has been studied and expected disagreement between our theoretical predictions and data has been obtained.

Figures (11)

• Figure 1: Feynman diagrams for the subprocess (\ref{['eq:RRg']}).
• Figure 2: Feynman diagrams for the subprocess (\ref{['eq:RRQQ']}).
• Figure 3: The fragmentation function $D(z,\mu^2)$ of $b$-quarks and gluons into $B$ mesons from Ref. FFB at the $\mu^2=100$ GeV$^2$ (solid curve for $b$-quark, pair-dotted for gluon) and $\mu^2=1000$ GeV$^2$ (dashed line for $b$-quark, dash-dotted for gluon).
• Figure 4: Transverse momentum distributions of $B^+$-meson production at Tevatron, $\sqrt S=1.96$ TeV (left-top); $B^0$ (right-top), $B^{+}$ (left-bottom), and $B_s^0$ (right-bottom) mesons at LHC, $\sqrt S=7$ TeV. Dashed line represents the contribution of gluon fragmentation, dash-dotted line -- the $b$-quark-fragmentation contribution, solid line is their sum. The CDF data at Tevatron are from the Ref. Tev196, the CMS data at LHC are from the Refs. CMSB0CMSBplusCMSBs, correspondingly.
• Figure 5: Theoretical predictions for the transverse momentum distributions of $B^0$ (top), $B^+$ (middle), $B^s$ (bottom) mesons in $pp$ scattering at $\sqrt S=14$ TeV and $|y|< 1.0$ obtained in the LO PRA. The notations as in the Fig. \ref{['fig:central']}.