Theoretical review of excited D*/Ds* mesons Xiang Liu Xiangliu@lzu.edu.cn Lanzhou University The 4th International Workshop on Charm Physics, Oct.21-24, 2010, IHEP, Beijing
Outline Excited charmed-strange meson Excited charmed meson Experiment + phenomenology Summary Xiang Liu @ Lanzhou U.
Charmed-strange state Xiang Liu @ Lanzhou U.
DsJ(2317) Four-quark state? The low mass puzzle of DsJ (2317) and DsJ (2460) DsJ(2317) Phys.Rev.Lett.90:242001,2003 Experimental masses are 100 MeV lower than the expected values in quark models S. Godfrey and R. Kokoski, PRD 43, 1679 (1991); S. Godfrey and N. Isgur, PRD 32, 189 (1985); M. Di Pierro and E. Eichten, PRD 64, 114004 (2001) Barnes, Close, Lipkin PRD68, 054006 (2003) Cheng, Hou, PLB566, 193 (2003) Chen, Li, PRL93, 232001 (2004) Four-quark state? Coupled-channel effect plays an important role to understand the low mass puzzle van Beveren, Rupp, PRL91, 012003 (2003) RSE EPJC32, 493 (2004) Dai, Li, Zhu, Zuo, EPJC55, 249 (2008) QSR Liu,Liu,Zhu PRD79, 094026 (2009) CHPT Phys.Rev.D68:032002,2003 DsJ(2460) C Charmed-strange meson Godfrey, PLB568, 254 (2003) Colangelo, De Fazio, PLB570, 180 (2003). Dai, Huang, Liu, Zhu, PRD68, 114011 (2003) Xiang Liu @ Lanzhou U.
Xiang Liu @ Lanzhou U. Phys.Rev.Lett.97:222001,2006 Phys.Rev.D80:092003,2009 Ds1(2710) DsJ(2860) DsJ(3040) hep-ex/0608031 Belle Xiang Liu @ Lanzhou U.
Obtained ratio of D*K/DK is consistent with experimental data. BaBar measurement Phys.Rev.D80:092003,2009 Xiang Liu @ Lanzhou U.
Charmed-strange meson Exotic state Quantum number Mixing 2 S +1 D 2 S 1 D Mutiquark state 3 1 More efforts are needed to distinguish different explanations to Ds1(2710) Xiang Liu @ Lanzhou U.
D*K/DK=0.36, which is smaller than experimental value It can be fully excluded since DsJ(2860)->D*K channel was observed at BaBar Phys.Rev.D80:092003,2009 BaBar data D*K/DK=0.36, which is smaller than experimental value Xiang Liu @ Lanzhou U.
Ratio of D*K/DK consistent with experimental data Babar data Phys.Rev.D80:092003,2009 Ratio of D*K/DK consistent with experimental data Xiang Liu @ Lanzhou U.
2S state DsJ(2710): 1 1D state DsJ(2860) Sun, Xiang Liu, PRD80, 074037 2S state DsJ(2710): 1 - 1D state DsJ(2860) Matsuki, Morii, Sudoh, EPJA31, 701 (2007) Chen, Wang, Zhang, PRD80, 071502 (2009) A semi-classic flux tube model Zhong, Zhao, PRD81, 014031 (2009) Constituent quark model with effective Lagrangian Colangelo, Fazio, arXiv:1001.1089 [hep-ph] Effective Lagrangian approach Xiang Liu @ Lanzhou U.
Charmed state Xiang Liu @ Lanzhou U.
The observations of D(2550), D(2610), D(2750) and D(2760) arXiv:1009.2076 Xiang Liu @ Lanzhou U.
1 3 Resonance parameters See Benitez’s talk to find more details - - - - 1 - 3 - or arXiv:1009.2076 2P or 1D state Xiang Liu @ Lanzhou U.
The possible assignments to D(2550), D(2610) and D(2760) D(2550) is 0 charmed meson since D(2550) is only observed in the invariant mass spectrum of D*π D(2610) can be assigned as 1 a pure 2S state Supported by the analysis of angular distribution and mass spectrum If D(2750)=D(2760), the spin-parity content of D(2760) can be either 1 or 3 because the observed decay D(2760)DK fully excludes 2 a pure 1D state or mixing state - D(2610) can also be as the partner of D(2760) Xiang Liu @ Lanzhou U.
Study strong decay behaviors of D(2550), D(2610) and D(2760) How to distinguish and test the possible assignments to D(2550), D(2610) and D(2760)? arXiv:1008.3120 Study strong decay behaviors of D(2550), D(2610) and D(2760) by Quark Pair Creation model Xiang Liu @ Lanzhou U.
Sun, Yu, Xiang Liu, Matsuki We expect further experiment to test it D(2550) The calculated total strong decay width of D(2550) as 2S state is far less than the BaBar data. Is the quark model calculation not appropriate in this case? Chiral Quark Model D(2550) narrow state X.H. Zhong, arXiv:1009.0359 Is 2S assignment not suitable to explain D(2550)? J =0 assignment is supported by the analysis of angular distribution and mass spectrum! Is D(2550) the overlap of several charmed mesons? P - Sun, Yu, Xiang Liu, Matsuki arXiv:1008.3120 - We expect further experiment to test it Xiang Liu @ Lanzhou U.
Sun, Yu, Xiang Liu, Matsuki, arXiv:1008.3120 D(2610) Vector charmed meson with mixing of 2S and 1D states Overlap between theoretical and experimental values A pure 2S charmed meson Ф=0 radians total decay width is far less than BaBar data Xiang Liu @ Lanzhou U.
Sun, Yu, Xiang Liu, Matsuki, arXiv:1008.3120 D(2760) Two times smaller than BaBar data Mixing of 2S and 1D as partner of D(2610) with J =1 A pure 1D charmed meson J =1 Ф=0 radians total decay width is far larger than BaBar data The 1D charmed meson with J =3 P - Xiang Liu @ Lanzhou U.
Summary Charmed-strange mesons DsJ(2860): DsJ(3040): the first radial excitation of Ds1(2460) 2P state (1+3) search for the remaining three 2P states in future experiment Charmed mesons Three newly observed charmed states D(2550), D(2610) and D(2760) 2S and 1D states Abundant excited D/Ds mesons were observed in the past 7 years! Good opportunity and full of the challenges Effort from theory and experiment Candidates for 2S and 1D states Search for the remaining 2S and 1D states Xiang Liu @ Lanzhou U.
Thank you for your attention! Xiang Liu @ Lanzhou U.