The masses of the recently reported by LHCb two pentaquark charmonium states Pc* (4380) and Pc* (4450) which are suggested to possess pentaquark configuration () have been estimated considering a dihadronic state cons...The masses of the recently reported by LHCb two pentaquark charmonium states Pc* (4380) and Pc* (4450) which are suggested to possess pentaquark configuration () have been estimated considering a dihadronic state consisting of a meson? and a baryon (uud). The binding energies of the states have been estimated with a van der Walls type of molecular interaction between the hadrons. A spin interaction has also been considered. Masses of these two states are well reproduced with the aforesaid molecular interaction which indicates that the multiquarks Pc* (4380) and Pc* (4450) can be well described as meson-baryon bound states.展开更多
High transverse momentum(pT)particle production is suppressed owing to the parton(jet)energy loss in the hot dense medium created in relativistic heavy-ion collisions.Redistribution of energy at low-to-modest pT has b...High transverse momentum(pT)particle production is suppressed owing to the parton(jet)energy loss in the hot dense medium created in relativistic heavy-ion collisions.Redistribution of energy at low-to-modest pT has been difficult to measure,owing to large anisotropic backgrounds.We report a data-driven method for background evaluation and subtraction,exploiting the away-side pseudorapidity gaps,to measure the jetlike correlation shape in Au+Au collisions at √sNN=200 GeV in the STAR experiment.The correlation shapes,for trigger particles pT>3GeV/c and various associated particle pT ranges within 0.5<pT<10GeV/c,are consistent with Gaussians,and their widths increase with centrality.The results indicate jet broadening in the medium created in central heavy-ion collisions.展开更多
We study the correlation between the trigger π and the associated J/ψ on near and away sides in Au+Au collisions at sNN^(1/2) = 200 GeV. In the region of trigger momentum pt 〉 4 GeV/c, the π spectrum is compose...We study the correlation between the trigger π and the associated J/ψ on near and away sides in Au+Au collisions at sNN^(1/2) = 200 GeV. In the region of trigger momentum pt 〉 4 GeV/c, the π spectrum is composed of thermal-shower and shower-shower recombinations in the frame work of the recombination model. We consider the azimuthal anisotropy in the quenched hard parton distribution and then calculate the elliptic flow parameter v2 of charmed mesons (J/ψ, D0 and Ds) for different centralities.展开更多
文摘The masses of the recently reported by LHCb two pentaquark charmonium states Pc* (4380) and Pc* (4450) which are suggested to possess pentaquark configuration () have been estimated considering a dihadronic state consisting of a meson? and a baryon (uud). The binding energies of the states have been estimated with a van der Walls type of molecular interaction between the hadrons. A spin interaction has also been considered. Masses of these two states are well reproduced with the aforesaid molecular interaction which indicates that the multiquarks Pc* (4380) and Pc* (4450) can be well described as meson-baryon bound states.
文摘High transverse momentum(pT)particle production is suppressed owing to the parton(jet)energy loss in the hot dense medium created in relativistic heavy-ion collisions.Redistribution of energy at low-to-modest pT has been difficult to measure,owing to large anisotropic backgrounds.We report a data-driven method for background evaluation and subtraction,exploiting the away-side pseudorapidity gaps,to measure the jetlike correlation shape in Au+Au collisions at √sNN=200 GeV in the STAR experiment.The correlation shapes,for trigger particles pT>3GeV/c and various associated particle pT ranges within 0.5<pT<10GeV/c,are consistent with Gaussians,and their widths increase with centrality.The results indicate jet broadening in the medium created in central heavy-ion collisions.
基金Supported by National Natural Science Foundation of China (10635020, 10775057)Ministry of Education of China (306022)Project IRT0624 and Programme of Introducing Talents of Discipline to Universities (B08033)
文摘We study the correlation between the trigger π and the associated J/ψ on near and away sides in Au+Au collisions at sNN^(1/2) = 200 GeV. In the region of trigger momentum pt 〉 4 GeV/c, the π spectrum is composed of thermal-shower and shower-shower recombinations in the frame work of the recombination model. We consider the azimuthal anisotropy in the quenched hard parton distribution and then calculate the elliptic flow parameter v2 of charmed mesons (J/ψ, D0 and Ds) for different centralities.