Measurement of the $\hat{I}\yen$ polarizations in $pp$ collisions at $\sqrt{s}$=7 and 8TeV

Abstract

The polarization of the $\hat{I}\yen (1S)$, $\hat{I}\yen (2S)$ and $\hat{I}\yen (3S)$mesons, produced in $pp$ collisions at centre-of-mass energies $\sqrt{s}$=7 and 8TeV, is measured using data samples collected by the LHCb experiment, corresponding to integrated luminosities of 1 and 2fb${}^{-1}$, respectively. The measurements are performed in three polarization frames, using $\hat{I}\yen \to \hat{I}{¼}^{+}\hat{I}{¼}^{-}$ decays in the kinematic region of the transverse momentum $p_T(\hat{I}\yen )<30GeV/c$, and rapidity $2.2<y(\hat{I}\yen )<4.5$. No large polarization is observed.

61 page, 15 figures, 28 tables. All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2017-028.html