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XYZ in the Future at BESIII

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XYZ in the Future at BESIII BES III future prospects in exotic hadron spectroscopy Kai ZHU (IHEP) on behalf of BESIII 6th International conference on New Frontiers in Physics (ICNFP 2017) Workshop on exotic hadrons 17-29 August 2017, Kolymbari, Crete, Greece BEPCII: Beijing Electron-Positron Collider II 北京 电子 - 正电子 对撞机 II CMS energy：ퟐ. ퟎ ∼ ퟒ. ퟔ GeV； Luminosity: ퟏ × ퟏퟎퟑퟑ풄풎−ퟐ풔−ퟏ MESON 2010 Kai Zhu 2 BESIII: BEijing Spectrometer III 北京 谱仪 III Physics: light hadron, charmonium, charm, R-value & QCD, new physics 2017-4-19 XYZ at BESIII 3 “Normal” hadrons • Exotic candidates figures from arXiv:1403.1254, S. Olsen 2017-4-19 XYZ at BESIII 4 “Normal” hadrons • Exotic candidates figures from arXiv:1403.1254, S. Olsen 2017-4-19 XYZ at BESIII 5 2017-8-17 XYZ states at BESIII 6 2017-8-17 XYZ states at BESIII 7 2017-8-17 XYZ states at BESIII 8 2017-8-17 XYZ states at BESIII 9 2017-8-17 XYZ states at BESIII 10 2017-8-17 XYZ states at BESIII 11 2017-8-17 XYZ states at BESIII 12 2017-8-17 XYZ states at BESIII 13 2017-8-17 XYZ states at BESIII 14 2017-8-17 XYZ states at BESIII 15 2017-8-17 XYZ states at BESIII 16 2017-8-17 XYZ states at BESIII 17 2017-8-17 XYZ states at BESIII 18 2017-8-17 XYZ states at BESIII 19 2017-8-17 XYZ states at BESIII 20 2017-8-17 XYZ states at BESIII 21 2017-8-17 XYZ states at BESIII 22 2017-8-17 XYZ states at BESIII 23 2017-8-17 XYZ states at BESIII 24 2017-8-17 XYZ states at BESIII 25 2017-8-17 XYZ states at BESIII 26 2017-8-17 XYZ states at BESIII 27 2017-8-17 XYZ states at BESIII 28 2017-8-17 XYZ states at BESIII 29 2017-8-17 XYZ states at BESIII 30 2017-8-17 XYZ states at BESIII 31 2017-8-17 XYZ states at BESIII 32 2017-8-17 XYZ states at BESIII 33 2017-8-17 XYZ states at BESIII 34 2017-8-17 XYZ states at BESIII 35 2017-8-17 XYZ states at BESIII 36 2017-8-17 A charmoniumXYZ statesstate at BESIII 37 2017-8-17 XYZ states at BESIII 38 2017-8-17 XYZ states at BESIII 39 2017-8-17 XYZ states at BESIII 40 2017-8-17 XYZ states at BESIII 41 2017-8-17 XYZ states at BESIII 42 2017-8-17 XYZ states at BESIII 43 2017-8-17 XYZ states at BESIII 44 2017-8-17 XYZ states at BESIII 45 2017-8-17 XYZ states at BESIII 46 2017-8-17 XYZ states at BESIII 47 2017-8-17 XYZ states at BESIII 48 2017-8-17 XYZ states at BESIII 49 2017-8-17 XYZ states at BESIII 50 2017-8-17 XYZ states at BESIII 51 2017-8-17 XYZ states at BESIII 52 2017-8-17 XYZ states at BESIII 53 2017-8-17 XYZ states at BESIII 54 2017-8-17 XYZ states at BESIII 55 2017-8-17 XYZ states at BESIII 56 2017-8-17 XYZ states at BESIII 57 2017-8-17 XYZ states at BESIII 58 2017-8-17 XYZ states at BESIII 59 2017-8-17 XYZ states at BESIII 60 2017-8-17 XYZ states at BESIII 61 2017-8-17 XYZ states at BESIII 62 2017-8-17 XYZ states at BESIII 63 2017-8-17 XYZ states at BESIII 64 2017-8-17 XYZ states at BESIII 65 2017-8-17 XYZ states at BESIII 66 2017-8-17 XYZ states at BESIII 67 2017-8-17 XYZ states at BESIII 68 2017-8-17 XYZ states at BESIII 69 2017-8-17 XYZ states at BESIII 70 2017-8-17 XYZ states at BESIII 71 2017-8-17 XYZ states at BESIII 72 2017-8-17 XYZ states at BESIII 73 2017-8-17 XYZ states at BESIII 74 2017-8-17 XYZ states at BESIII 75 2017-8-17 XYZ states at BESIII 76 푒+푒− → 훾푋 3872 푌 4260 , 푌 4360 in + − 휋+휋−푋(3823) 푒 푒 → 휔휒푐퐽, 훾휒푐퐽 ′ 휂퐽/휓, 휂 퐽/휓, 휂ℎ푐 휋휋ℎ푐, 휋휋퐽/휓,훾휂푐 X Y Z ±,0 ∗ 푍푐 3900 [휋퐽/휓,퐷퐷 ] No light hadron final states from ±,0 ∗ ∗ 푍푐 4240 [휋ℎ푐,퐷 퐷 ] XYZ decay is observed. Complex structured observed in 휋휓(3686). 2016-11-25 XYZ future at BESIII 77 Characteristics and trends in XYZ study at BESIII • Systematic Ex. 휋0 휂 휂 ′ 푐 휂 퐽/휓 휋+휋− 훾 × 휒 휂휂 × 푐퐽 ℎ 휋+휋−휋0(휔) 푐 휓′ 휂휋휋 (∗) (∗) 휋0휋0 퐷 퐷 퐾+퐾− 휙 2017-8-17 XYZ states at BESIII 78 Characteristics and trends in XYZ study at BESIII • More amplitude analyses 2017-8-17 XYZ states at BESIII 79 XYZ Data: we already have ~12 fb−1 + R-scan data sets 2017-8-17 XYZ states at BESIII 80 A big plan for XYZ 2017-8-17 XYZ states at BESIII 81 Further plan • A few high statistics points (around 4.2, 4.3 4.4 GeV? ) – Primary focus: further study on 푍푐 states. • More high energy data (between 4.5 and 4.6 GeV? ) – Primary focus: line-shapes, Λ푐Λ푐 threshold, more phase space • > 4.6 GeV (the present upper energy of BEPCII) – R&D is on-going • Others (suggestions from theorists?) – Specific predictions are extremely welcome. 2017-8-17 XYZ states at BESIII 82 XYZ in the future at • BESIII has observed/measured XYZ states. – From experiment side, 푍푐 3900 , 푍푐 4020 , and 푌(4260) are solidly established based on BESIII measurements. • Our knowledge of XYZ has been significantly improved. However, there are still many puzzles – One or two states when two resonances are close? – Complex structures are observed and difficult to describe. – Some expected states or decay modes have not been observed. – Nature of these states. – … • With more data and inputs from theorists, we will better understand these exotic states. 2016-11-25 XYZ future at BESIII 83 Thank you! 2017-8-17 XYZ states at BESIII 84.
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