Is the 1(-+) meson a hybrid?

	Is the 1(-+) meson a hybrid?
	Yang YB(杨一玻); 陈莹;Yang, YB; Chen, Y; Li, G; Liu, KF
刊名	PHYSICAL REVIEW D
	2012
卷号	86 期号:9 页码:94511
英文摘要	We calculate the vacuum to meson matrix elements of the dimension-4 operator (psi) over bar gamma(4)(D) over left right arrow (i)psi and dimension-5 operator (psi) over bar epsilon(ijk)gamma(j)psi B-k of the 1(-+) meson on the lattice and compare them to the corresponding matrix elements of the ordinary mesons to discern if it is a hybrid. For the charmoniums and strange quarkoniums, we find that the matrix elements of 1(-+) are comparable in size as compared to other known q (q) over bar mesons. They are particularly similar to those of the 2(++) meson, since their dimension-4 operators are in the same Lorentz multiplet. Based on these observations, we find no evidence to support the notion that the lowest 1(-+) mesons in the c (c) over bar and s (s) over bar regions are hybrids. As far as the exotic quantum number is concerned, the nonrelativistic reduction reveals that the leading terms in the dimension-4 and dimension-5 operators of 1(-+) are identical up to a proportional constant and it involves a center- of- mass momentum operator of the quark-antiquark pair. This explains why 1(-+) is an exotic quantum number in the constituent quark model where the center of mass of the q (q) over bar is not a dynamical degree of freedom. Since QCD has gluon fields in the context of the flux tube which is appropriate for heavy quarkoniums to allow the valence q (q) over bar to recoil against them, it can accommodate such states as 1(-+). By the same token, hadronic models with additional constituents besides the quarks can also accommodate the q (q) over barq center-of-mass motion. To account for the quantum numbers of these q (q) over bar mesons in QCD and hadron models in the nonrelativistic case, the parity and total angular momentum should be modified to P = (-)(L+1+1) and (J) over right arrow = (L) over right arrow + (l) over right arrow + (S) over right arrow, where L is the orbital angular momentum of the q (q) over bar pair in the meson.
学科主题	Astronomy & Astrophysics; Physics
收录类别	SCI
WOS记录号	WOS:000311142700004
公开日期	2016-05-03
内容类型	期刊论文
源URL	[http://ir.ihep.ac.cn/handle/311005/224611]
专题	高能物理研究所_理论物理室
推荐引用方式 GB/T 7714	Yang YB,陈莹；Yang, YB,Chen, Y,et al. Is the 1(-+) meson a hybrid?[J]. PHYSICAL REVIEW D,2012,86(9):94511.
APA	杨一玻,陈莹；Yang, YB,Chen, Y,Li, G,&Liu, KF.(2012).Is the 1(-+) meson a hybrid?.PHYSICAL REVIEW D,86(9),94511.
MLA	杨一玻,et al."Is the 1(-+) meson a hybrid?".PHYSICAL REVIEW D 86.9(2012):94511.