Dergi makalesi Açık Erişim

Production of $\omega $ mesons in pp collisions at $\sqrt{s}=7\phantom{\rule{0.166667em}{0ex}}\text{TeV}$

2020    CERN İşbirliği

The invariant differential cross section of inclusive $\omega \left(782\right)$ meson production at midrapidity ( $|y|<0.5$ ) in pp collisions at $\sqrt{s}=7\phantom{\rule{0.166667em}{0ex}}\text{TeV}$ was measured with the ALICE detector at the LHC over a transverse momentum range of $2<{p}_{T}<17\phantom{\rule{0.166667em}{0ex}}\text{GeV}/c$ . The $\omega $ meson was reconstructed via its $\omega \to {\pi }^{+}{\pi }^{-}{\pi }^{0}$ decay channel. The measured $\omega $ production cross section is compared to various calculations: PYTHIA 8.2 Monash 2013 describes the data, while PYTHIA 8.2 Tune 4C overestimates the data by about 50%. A recent NLO calculation, which includes a model describing the fragmentation of the whole vector-meson nonet, describes the data within uncertainties below $6\phantom{\rule{0.166667em}{0ex}}\text{GeV}/c$ , while it overestimates the data by up to 50% for higher ${p}_{T}$ . The $\omega /{\pi }^{0}$ ratio is in agreement with previous measurements at lower collision energies and the PYTHIA calculations. In addition, the measurement is compatible with transverse mass scaling within the measured ${p}_{T}$ range and the ratio is constant with ${C}^{\omega /{\pi }^{0}}=0.67±0.03\phantom{\rule{0.333333em}{0ex}}\text{(stat)}\phantom{\rule{0.333333em}{0ex}}±0.04\phantom{\rule{0.333333em}{0ex}}\text{(sys)}\phantom{\rule{0.333333em}{0ex}}$ above a transverse momentum of $2.5\phantom{\rule{0.166667em}{0ex}}\text{GeV}/c$ .