Hadroproduction of Υ(nS) above the B B threshold and implications for Y b (10890)

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1 Hadroproduction of Υ(nS) above the B B threshold and implications for Y b (10890) Ahmed Ali DESY 3. July 2014 ICHEP-2014, Valencia [Based on: AA, Christian Hambrock, and Wei Wang, Phys.Rev. D88 (2013) 5, ] Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

2 Exotica Belle & Other Experiments [Zupanc et al. 09], [Bondar et al., PRL 12], [Liu et al., 13], [Ablikim et al., 13] State M (MeV) Γ (MeV) J PC Decay Modes Production Modes Also observed by date e + e (ISR) Ys(2175) 2175 ± 8 58 ± 26 1 φf 0 (980) J/ψ ηys(2175) BaBar, BESII 2006 π + π J/ψ, BaBar X(3872) ± 0.17 < γj/ψ,dd B KX(3872), p p CDF, D0, LHCb 2003 Z(3900) 3899 ± 6 46 ± π ± J/ψ Y(4260) Z(3900)π BESIII 2013 X(3915) 3914 ± /2 ++ ωj/ψ γγ X(3915) 2009 Z(3930) 3929 ± 5 29 ± D D γγ Z(3940) 2009 DD (not D D X(3940) 3942 ± 9 37 ± 17 0?+ or ωj/ψ) e + e J/ψX(3940) 2005 Y(3940) 3943 ± ± 34??+ ωj/ψ (not DD ) B KY(3940) BaBar 2005 Y(4008) π + π J/ψ e + e (ISR) 2005 Z(4020) 4022 ± 3 6 ± π ± J/ψ Y(4260) Z(4020)π BESIII(only) 2013 Z(4025) 4026 ± 5 25 ± π ± J/ψ Y(4260) Z(4025)π BESIII(only) 2013 X(4160) 4156 ± ?+ D D (not D D) e + e J/ψX(4160) 2008 Y(4260) 4264 ± ± 22 1 π + π J/ψ e + e (ISR) BaBar, CLEO 2005 Y(4350) 4361 ± ± 18 1 π + π ψ e + e (ISR) BaBar 2007 X(4630) Λ c + Λ c e + e (ISR) 2008 Y(4660) 4664 ± ± 15 1 π + π ψ e + e (ISR) 2007 Z(4050) ? π ± χ c1 B KZ ± (4050) 2008 Z(4250) ? π ± χ c1 B KZ ± (4250) 2008 Z(4430) 4433 ± ? π ± ψ B KZ ± (4430) LHCb 2007 Z b (10610) 10, 607 ± ± π ± h b (1, 2P), π ± Υ(1, 2, 3S) Y b /Υ(5S) Z b (10610)π 2011 Z b (10650) 10, 652 ± ± π ± h b (1, 2P), π ± Υ(1, 2, 3S) Y b /Υ(5S) Z b (10650)π 2011 Y b (10890) 10, 890 ± 3 55 ± 9 1 π + π Υ(1, 2, 3S) e + e Y b 2008 Light states [PDG] : a 0 (980) in 1965, σ(600) now 500 in 1972, f 0 (980) in 1979, κ(980) in 1997 discussion Ahmed reopened: Ali (DESY) [ t Hooft, Isidori, Heavy Maiani, Multiquark Polosa, States Riquer, PLB 08] ICHEP-2014, Valencia, / 14

3 Exotica Belle & Other Experiments [Zupanc et al. 09], [Bondar et al., PRL 12], [Liu et al., 13], [Ablikim et al., 13] State M (MeV) Γ (MeV) J PC Decay Modes Production Modes Also observed by date e + e (ISR) Ys(2175) 2175 ± 8 58 ± 26 1 φf 0 (980) J/ψ ηys(2175) BaBar, BESII 2006 π + π J/ψ, BaBar X(3872) ± 0.17 < γj/ψ,dd B KX(3872), p p CDF, D0, LHCb 2003 Z(3900) 3899 ± 6 46 ± π ± J/ψ Y(4260) Z(3900)π BESIII 2013 X(3915) 3914 ± /2 ++ ωj/ψ γγ X(3915) 2009 Z(3930) 3929 ± 5 29 ± D D γγ Z(3940) 2009 DD (not D D focus here: X(3940) 3942 ± 9 37 ± 17 0?+ or ωj/ψ) e + e J/ψX(3940) 2005 Y(3940) 3943 ± ± 34 Z??+ c (3900, ωj/ψ 4020, (not DD4025) ) B KY(3940) BaBar 2005 Y(4008) π + π J/ψ e + e (ISR) Z(4020) 4022 ± 3 6 ± 4 Y1 c (4260) + π ± J/ψ Y(4260) Z(4020)π BESIII(only) 2013 Z(4025) 4026 ± 5 25 ± π ± J/ψ Y(4260) Z(4025)π BESIII(only) 2013 Z X(4160) 4156 ± b (106XX)?+ D D 65 (not D D) e + e J/ψX(4160) 2008 Y(4260) 4264 ± ± 22 Y1 b (10890) π + π J/ψ e + e (ISR) BaBar, CLEO 2005 Y(4350) 4361 ± ± 18 1 π + π ψ e + e (ISR) BaBar 2007 X(4630) Λ c + Λ c e + e (ISR) 2008 Y(4660) 4664 ± ± 15 1 π + π ψ e + e (ISR) 2007 Z(4050) ? π ± χ c1 B KZ ± (4050) 2008 Z(4250) ? π ± χ c1 B KZ ± (4250) 2008 Z(4430) 4433 ± ? π ± ψ B KZ ± (4430) LHCb 2007 Z b (10610) 10, 607 ± ± π ± h b (1, 2P), π ± Υ(1, 2, 3S) Y b /Υ(5S) Z b (10610)π 2011 Z b (10650) 10, 652 ± ± π ± h b (1, 2P), π ± Υ(1, 2, 3S) Y b /Υ(5S) Z b (10650)π 2011 Y b (10890) 10, 890 ± 3 55 ± 9 1 π + π Υ(1, 2, 3S) e + e Y b 2008 Light states [PDG] : a 0 (980) in 1965, σ(600) now 500 in 1972, f 0 (980) in 1979, κ(980) in 1997 discussion Ahmed reopened: Ali (DESY) [ t Hooft, Isidori, Heavy Maiani, Multiquark Polosa, States Riquer, PLB 08] ICHEP-2014, Valencia, / 14

4 Relation c c & b b Understanding heavy exotica means to understand both sectors! Only 3 candidates in b b expect lot more at Belle-II & LHC Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

5 Relation c c & b b Understanding heavy exotica means to understand both sectors! Only 3 candidates in b b expect lot more at Belle-II & LHC Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

6 Why is the anomalous? Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

7 Tetraquark vs. Rescattering Tetraquark & Rescattering: Two rivals in explaining Belle enigma Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

8 Tetraquark vs. Rescattering Tetraquark & Rescattering: Two rivals in explaining Belle enigma Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

9 Tetraquark vs. Rescattering Tetraquark & Rescattering: Two rivals in explaining Belle enigma Rough estimate in Rescattering [Meng, Chao, PRD 08] : Γ Υ(6S) Υ(1,2,3S)ππ Γ Υ(5S) Υ(1,2,3S)ππ ( Problem of approach: introduced ad hoc form factor to suppress phase space enhancement ) Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

10 Tetraquark vs. Rescattering Tetraquark & Rescattering: Two rivals in explaining Belle enigma Rough estimate in Rescattering [Meng, Chao, PRD 08] : Γ Υ(6S) Υ(1,2,3S)ππ Γ Υ(5S) Υ(1,2,3S)ππ ( Problem of approach: introduced ad hoc form factor to suppress phase space enhancement ) Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

11 [bq][ b q] Constituent Model Spectrum [Ali, Hambrock, Ahmed, Aslam, PLB 10] HQ symmetry motivates fixing (diquark mass estimate from charm 30 MeV off) states are iso-doublets q = u, d tetraquark Z b masses do not agree with Belle However tetraquarks with mixing & self energy corrections in principle allowed in parts of parameter space [Ali, Hambrock, Wang, PRD 11] Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

12 Spectroscopy above Threshold Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

13 Spectroscopy above Threshold multiquark states typically above hadronic thresholds few data for b b (c c advantage ISR & B decays) blank area likely full of surprises important to understand b b & c c simultaneously Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

14 Spectroscopy above Threshold multiquark states typically above hadronic thresholds few data for b b (c c advantage ISR & B decays) blank area likely full of surprises important to understand b b & c c simultaneously Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

Spectroscopy above Threshold multiquark states typically above hadronic thresholds few data for b b (c c advantage ISR & B decays) blank area likely full of surprises important to understand b b & c

15 Spectroscopy above Threshold multiquark states typically above hadronic thresholds few data for b b (c c advantage ISR & B decays) blank area likely full of surprises important to understand b b & c c simultaneously LHCb promising to map uncharted b b region including more than J PC = 1 caveat: hadroproduction more complicated than electroproduction Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

16 Hadroproduction of Bottomonia µ + µ channel: Common particle detection for bottomonia Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

17 Hadroproduction of Bottomonia µ + µ channel: Common particle detection for bottomonia Above threshold difficult (BR(µ + µ )drops) present research focused on 1S, 2S, 3S Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

18 Hadroproduction of Bottomonia µ + µ channel: Common particle detection for bottomonia Above threshold difficult (BR(µ + µ )drops) present research focused on 1S, 2S, 3S Different final states (e.g. µ + µ π + π ) allow for exotic searches Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

µ + µ π + π ) allow for exotic searches [AA, Hambrock, Wang,13] : Acquire knowledge of bottomonia above

19 Hadroproduction of Bottomonia µ + µ channel: Common particle detection for bottomonia Above threshold difficult (BR(µ + µ )drops) present research focused on 1S, 2S, 3S Different final states (e.g. µ + µ π + π ) allow for exotic searches [AA, Hambrock, Wang,13] : Acquire knowledge of bottomonia above hadronic thresholds (NRQCD) clarify nature of observed states Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

20 NRQCD details Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

21 NRQCD details Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

22 NRQCD details Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

23 NRQCD details Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

24 NRQCD details Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

25 NRQCD details partonic channels (include NLO for CS): gg Υ[ 3 S 1 1 ] + g, gg Υ[1 S 8 0, 3 S 8 1 ] + g gq Υ[ 1 S 8 0, 3 S 8 1 ] + q, q q Υ[1 S 8 0, 3 S 8 1 ] + g calculate p t distribution - take p t > 3 GeV avoid soft gluon resummation ( ) p Υ = M 2 Υ + p2 t cosh(y), p t, 0, M 2Υ + p2 t sinh(y) Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

Recipe: Ingredients Color-Singlet [CS] LDMEs from potential models via VRW (well-known) model dependence enters via B(Υ(6S) Υ(nS)ππ ) estimate currently

26 Recipe: Ingredients Color-Singlet [CS] LDMEs from potential models via VRW (well-known) model dependence enters via B(Υ(6S) Υ(nS)ππ ) estimate currently Color-Octet [CO] LDEMEs not known sizable Ahmed Ali (DESY) Heavy Multiquark States large uncertainties if contribution ICHEP-2014, Valencia, / 14

27 Result σ N σn /ho[n ]i O(pb) expected (no gaussian errors) Ahmed Ali (DESY) Heavy Multiquark O(pb) sufficient to bestates observed! ICHEP-2014, Valencia, / 14

28 Search for X b decaying into Υ(1S)π + π [CMS Collaboration; PL B727, 57 (2013)] Exclusion limits as a function of the X b mass at 95% C.L. Υ(1S)ππ) b B(X B(Υ(2S) Υ(1S)ππ) CMS Preliminary s = 8 TeV -1 L = 20.7 fb Median Expected Observed ± 1σ Expected ± 2σ Expected R = σ Xb σ Υ(2S) M Xb [GeV] For X b = Y b (10876), the limit is: Using the CMS measurement σ(pp Υ(2S)X)B(Υ(2S) µ + µ ) = 1.55nb σ(pp X b Υ(1S)π + π ) σ(pp Υ(2S) Υ(1S)π + π ) < 0.02, we get σ(pp X b Υ(1S)π + π )B(Υ(1S) µ + µ ) < 7.1 pb This is typically O(10)away from theoretical estimates Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

29 Expectations Tetraquark refuted: π + π µ + µ channel opens new possibilities for NRQCD and quarkonia production due to large Br Tetraquark confirmed: important exotic state in b b confirmed HQ pattern established Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

Conclusions Important puzzle: Tetraquarks provide a credible explanation for BELLE anomaly @Υ(5S) Predicted spectra for Y b (10980) provide crucial tests - final proof needed!

30 Conclusions Important puzzle: Tetraquarks provide a credible explanation for BELLE Predicted spectra for Y b (10980) provide crucial tests - final proof needed! Hadrobroduction able to decide disputed nature of Y b (10980) Outlook Dedicated lattice studies to determine hadronic MEs Hadroproduction of bottomonia & tetraquarks very interesting in the near future! heaps of new states expected! Ahmed Ali (DESY) Heavy Multiquark States ICHEP-2014, Valencia, / 14

Chengping Shen: Beihang University, Beijing XVI International Conference on Hadron Spectroscopy (Hadron 2015) September, 2015, JLab, USA

Chengping Shen: Beihang University, Beijing XVI International Conference on Hadron Spectroscopy (Hadron 2015) 13-18 September, 2015, JLab, USA Hadrons: normal & exotic Quark model: hadrons are composed