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μ + μ - channel and ψ (2s ) signals at 7 TeV

μ + μ - channel and ψ (2s ) signals at 7 TeV. Data for periods D6 + E + F used for ψ (2s) Used D3PD like

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μ + μ - channel and ψ (2s ) signals at 7 TeV

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  1. μ+μ- channel and ψ(2s) signals at 7 TeV Data for periods D6 + E + F used for ψ(2s) Used D3PD like data10_7TeV.00158632.physics_MuonswBeam.merge.NTUP_WZ* or group10.phys-sm.data10_7TeV.00160472.physics_Muons.recon.ESD.f280.WZphys.100612.01.D3PD V.Nikolaenko 21 Sep 2010

  2. Z0 →μ+μ- signal at full statistics available at the time being (3.1 pb-1 )

  3. Preselection for ψ(2s) (90% of full statistics) • Preselection - starting from run 159202 [periodD6] selected events with L1_MU0 or L1_MU6 trigger; selected StacoMuon with abs(all_st_d0_pr) <2.0 and abs(all_st_z0_pr)<100 • selected events with mu_staco_n >1; • selected events with at least one p_t(mu+-)>5 GeV • selected events with mu+mu- pair • J/psi selecttion: 3.0<m(mu+mu-)<3.2 GeV;

  4. Track selection • impact parameters with respect to primary vertex, requested abs(trk_d0_wrtPV)<2.0 and abs(trk_z0_wrtPV)*sin(theta) < 2.0; • No p_t cut for tracks; • Rejected tracks matched with muons; • taken 2-particle combinations with opposite charge; • difference m(mu+mu-pi+pi-)-m(mu+mu-) - m(mu+mu-) considered;

  5. m(μ+ μ- ) Staco selection

  6. General pattern below 20 GeV Seen ω(782), φ(1020), J/ψ, ψ(2s), Υ(1s)

  7. Υ(1s)

  8. J/ψ fit by two gaussians + BG

  9. Ψ(2s)→μ+μ-

  10. Ψ(2s)→μ+μ-π+π-

  11. η for J/ψ and ψ(2s) 3.0<m<3.2 for J/ψ; 3.53<m<3.84 forψ(2s)

  12. Pt for J/ψ and ψ(2s) 3.0<m<3.2 for J/ψ; 3.53<m<3.84 forψ(2s)

  13. Conclusions • ψ(2s) seen in (μ+μ-) mode (2676+-115 evt.) and in (μ+μ-π+π-) mode (1931+-199 evt.) • Large background in both channels, particularly for (μ+μ-π+π-) channel. • The X(3872) not seen yet • From N(J/ψ→μμ)=42890±320, one can get a very crude estimation of R=σ(psi(2s))*BR(μμ)/σ(J/ψ)*BR(μ)=0.062±0.003;

  14. Ψ(2s) to J/ψ ratio • This value can be compared with similar ratio obtained at CDF (see F.Abe et al., Phys.Rev.Lett.79:572-577,1997), at pt > 5 GeV and -0.6<η<0.6, σ(J/ψ)*BR(μμ)=17.4±0.1+2.6-1.8 nb; σ(ψ(2s)*BR(μμ)=0.57±0.04±0.09 nb; which gives (at different energy, in another transverse momentum and pseudorapidity range ) R = 0.033+-0.008; agreement is not too bad

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