Measurement of the ${\rm Y}$ polarizations in $pp$ collisions at $\sqrt{s}$=7 and 8TeV

Abstract

The polarization of the ${\rm Y}(1S)$, ${\rm Y}(2S)$ and ${\rm Y}(3S)$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 ${\rm Y}\to {\mu }^{+}{\mu }^{-}$ decays in the kinematic region of the transverse momentum $p_T({\rm Y})<30GeV/c$, and rapidity $2.2<y({\rm Y})<4.5$. No large polarization is observed.

arXiv comment61 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

References in corpus (49)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• Rigorous QCD Analysis of Inclusive Annihilation and Production of Heavy Quarkonium
• Heavy quarkonium: progress, puzzles, and opportunities
• LHCb Detector Performance
• PHOTOS Monte Carlo: a precision tool for QED corrections in Z and W decays
• sPlot: a statistical tool to unfold data distributions
• The LHCb Trigger and its Performance in 2011
• Decay Chain Fitting with a Kalman Filter
• Color-Octet Fragmentation and the psi' Surplus at the Tevatron
• Performance of the LHCb muon system
• Measurement of the track reconstruction efficiency at LHCb
• QCD corrections to J/psi and Upsilon production at hadron colliders
• Upsilon production at the Tevatron and the LHC
• Measurement of the Inclusive Upsilon production cross section in pp collisions at sqrt(s)=7 TeV
• Towards the experimental clarification of quarkonium polarization
• Observation of $J/\psi$ pair production in pp collisions at $\sqrt{s}=7TeV$
• QCD corrections to J/psi polarization of hadronproduction at Tevatron and LHC
• Measurement of $J/\psi$ polarization in $pp$ collisions at $\sqrt{s}=7$ TeV
• On the mechanisms of heavy-quarkonium hadroproduction
• Measurement of CP violation and the B_s^0 meson decay width difference with B_s^0\to J/ψK^+ K^- and B_s^0\to J/ψπ^+π^- decays
• Measurement of the Y(1S), Y(2S), and Y(3S) polarizations in pp collisions at sqrt(s) = 7 TeV
• Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS
• Inelastic photoproduction of polarised $J/\psi$
• Measurement of Upsilon production in 7 TeV pp collisions at ATLAS
• Measurement of Upsilon production in pp collisions at \sqrt{s} = 7 TeV
• Quarkonium production in the LHC era: a polarized perspective
• Performance of the Muon Identification at LHCb
• Production of J/psi and Upsilon mesons in pp collisions at sqrt(s) = 8 TeV
• Complete next-to-leading-order study on the yield and polarization of Upsilon(1S,2S,3S) at the Tevatron and LHC
• Measurement of $\psi (2S)$ polarisation in $pp$ collisions at $\sqrt{s}=7$ TeV
• Rotation-invariant relations in vector meson decays into fermion pairs
• ${\rm Y}(nS)$ and ${\chi }_b(nP)$ production at hadron colliders in nonrelativistic QCD
• Measurement of the polarization of the ${\rm Y}(1S)$ and ${\rm Y}(2S)$ states in $p\bar{p}$ collisions at $\sqrt{s}=$1.96 TeV
• A new approach to quarkonium polarization studies
• Measurement of ${\rm Y}$ production in $pp$ collisions at $\sqrt{s}$= 13 TeV
• Observation of a narrow mass state decaying into Upsilon(1S) + gamma in ppbar collisions at sqrt(s) = 1.96 TeV
• sFit: a method for background subtraction in maximum likelihood fit
• Measurements of Angular Distributions of Muons From Upsilon Meson Decays in p p-bar Collisions at sqrt(s)=1.96 TeV
• Forward production of ${\rm Y}$ mesons in $pp$ collisions at $\sqrt{s}=7$ and 8TeV
• An Updated Study for ${\rm Y}$ Production and Polarization at the Tevatron and LHC
• Model-independent constraints on the shape parameters of dilepton angular distributions
• Measurement of the ${\chi }_b(3P)$ mass and of the relative rate of ${\chi }_{b1}(1P)$ and ${\chi }_{b2}(1P)$ production
• Measurement of Upsilon production in pp collisions at sqrt{s}=2.76 TeV
• Measurement of the fraction of \Y1S originating from \chib1P decays in $pp$ collisions at $\sqrt{s} = 7\tev$
• Angular distribution and rotations of frame in vector meson decays into lepton pairs
• Rotation-invariant observables in parity-violating decays of vector particles to fermion pairs
• J/psi and Upsilon Polarization in Hadronic Production Processes
• Kinematic Azimuthal Asymmetries and Lam-Tung Relation

Cited by in corpus (12)

• Measurement of the ${\rm Y}$(1S) pair production cross section and search for resonances decaying to ${\rm Y}$(1S)${\mu }^{+}{\mu }^{-}$ in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Lorentz Boost Networks: Autonomous Physics-Inspired Feature Engineering
• First measurement of quarkonium polarization in nuclear collisions at the LHC
• Heavy Flavour Physics and CP Violation at LHCb: a Ten-Year Review
• Production and polarization of prompt ${\rm Y}$($n$S) in the improved color evaporation model using the $k_T$-factorization approach
• Inclusive quarkonium production in pp collisions at $\sqrt{s}=5.02$ TeV
• Observation of the ${\rm Y}$(3S) meson and suppression of ${\rm Y}$ states in PbPb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• The complete study on polarization of ${\rm Y}(nS)$ hadroproduction at QCD next-to-leading order
• From prompt to direct J/$\psi$ production: new insights on the ${\chi }_{c1}$ and ${\chi }_{c2}$ polarizations and feed-down contributions from a global-fit analysis of mid-rapidity LHC data
• NRQCD colour-octet expansion vs LHC quarkonium production: signs of a hierarchy puzzle?
• Experimental review of the ${\rm Y}(1S,2S,3S)$ physics at $e^{+}{e}^{-}$ colliders and the LHC
• J/$\psi$ and ${\rm Y}$(1S) production in jets at LHC energies