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

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 $2.0\text{ GeV}<p_T<18\text{ GeV}$ and $2.2<\eta <4.75$, which agrees with $A_p=-0.96\pm 0.26\pm 0.18\%$ 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 $\sim 1-3\%$ and should be measurable.

Comments: To be published in the proceedings of CHARM-2015, Detroit, MI, 18-22 May 2015