Measurement of K${}^{\ast }$(892)${}^{\pm }$ production in inelastic pp collisions at the LHC

The first results on K${}^{\ast }$(892)${}^{\pm }$ resonance production in inelastic pp collisions at LHC energies of $\sqrt{s}=5.02$, 8, and 13 TeV are presented. The K${}^{\ast }$(892)${}^{\pm }$ has been reconstructed via its hadronic decay channel K${}^{\ast }$(892)${}^{\pm }$ $\to$ $\mathrm {K^0_S}$ $+{\pi }^{\pm }$ with the ALICE detector. Measurements of transverse momentum distributions, $p_{\mathrm{T}}$-integrated yields, and mean transverse momenta for charged K${}^{\ast }$(892) are found to be consistent with previous ALICE measurements for neutral K${}^{\ast }$(892) within uncertainties. For $p_{$\mathrm{T}$}

1$GeV\mathrm{/}$c$theK$^{*}$(892)$^{$\pm$}$ transverse momentum spectra become harder with increasing centre-of-mass energy from 5.02 to 13 TeV, similar to what previously observed for charged kaons and pions. For $p_{\mathrm{T}}<1$ GeV/$c$ the K${}^{\ast }$(892)${}^{\pm }$ yield does not evolve significantly and the abundance of K${}^{\ast }$(892)${}^{\pm }$ relative to K is rather independent of the collision energy. The transverse momentum spectra, measured for K${}^{\ast }$(892)${}^{\pm }$ at midrapidity in the interval $0<p_{\mathrm{T}}<15$ GeV/$c$, are not well described by predictions of different versions of PYTHIA 6, PYTHIA 8 and EPOS-LHC event generators. These generators reproduce the measured $p_{\mathrm{T}}$-integrated K${}^{\ast \pm }$/K ratios and describe well the momentum dependence for $p_{\mathrm{T}}<2$ GeV/$c$.