Production asymmetries of $D^{\pm}$, $\Lambda_c^{+}/\Lambda_c^{-}$ and $\Lambda_b^0/\overline{\Lambda}_b^0$ at the LHC from heavy quark recombination mechanism

TL;DR

This paper uses the heavy quark recombination mechanism to calculate and predict production asymmetries of heavy hadrons at the LHC, matching experimental data for D mesons and providing new predictions for Lambda baryons.

Contribution

The paper applies the heavy quark recombination mechanism to accurately reproduce D meson asymmetries and predicts measurable Lambda baryon asymmetries at the LHC.

Findings

Calculated D meson asymmetry of about -1% matches LHCb data.

Predicted Lambda_c and Lambda_b asymmetries of 1-3% are within measurable range.

Distributions in eta and pT agree well with experimental results.

Abstract

The asymmetry in the forward region production cross section of $D^{\pm}$ is calculated using the heavy quark recombination mechanism for $pp$ collisions at $7$~TeV. By suitable choices of four nonperturbative parameters, our calculated results can reproduce those obtained at LHCb. We find $A_p\sim-1\%$ when integrated over $2.0\textrm{ GeV}<p_T<18\textrm{ GeV}$ and $2.2<\eta<4.75$, which agrees with $A_p=-0.96\pm0.26\pm0.18\%$ as measured by LHCb. Furthermore, the calculated distributions in $\eta$ and $p_T$ agree reasonably well with those obtained at LHCb. Using the heavy quark recombination mechanism, we also make predictions on the production asymmetries of $\Lambda_c^{+}/\Lambda_c^{-}$ and $\Lambda_b^0/\overline{\Lambda}_b^0$ for $pp$ collisions at $7$~TeV and $14$~TeV in the forward region. We find that the integrated asymmetries for these $\Lambda$ baryons in the LHCb region are of the order of $\sim1-3\%$ and should be measurable.