Measurement of $D_s^{\pm}$ production asymmetry in $pp$ collisions at $\sqrt{s} =7$ and 8 TeV

TL;DR

This paper measures the production asymmetry of $D_s^{\pm}$ mesons in proton-proton collisions at 7 and 8 TeV, finding evidence of a nonzero asymmetry with statistical significance, using data from the LHCb experiment.

Contribution

First measurement of $D_s^{\pm}$ production asymmetry in $pp$ collisions at these energies, providing new insights into charm meson production asymmetries.

Findings

Evidence of nonzero $D_s^{\pm}$ asymmetry at 3.3 sigma significance.

No kinematic dependence of the asymmetry observed.

Measurement covers a broad range of transverse momentum and rapidity.

Abstract

The inclusive $D_s^{\pm}$ production asymmetry is measured in $pp$ collisions collected by the LHCb experiment at centre-of-mass energies of $\sqrt{s} =7$ and 8 TeV. Promptly produced $D_s^{\pm}$ mesons are used, which decay as $D_s^{\pm}\to\phi\pi^{\pm}$, with $\phi\to K^+K^-$. The measurement is performed in bins of transverse momentum, $p_{\rm T}$, and rapidity, $y$, covering the range $2.5<p_{\rm T}<25.0$ GeV$/c$ and $2.0<y<4.5$. No kinematic dependence is observed. Evidence of nonzero $D_s^{\pm}$ production asymmetry is found with a significance of 3.3 standard deviations.