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arXiv 0811.2399hep-ph
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$D_s$和$B_s$介子的耦合道分析

The coupled-channel analysis of $D_s$ and $B_s$ mesons

A. M. Badalian, Yu. A. Simonov, M. A. Trusov

摘要:

在耦合沟道模型的框架下,计算了$D_s$和$B_s$介子的$P$-波激发的质量位移。与$DK$和$BK$通道的耦合由有效手征拉格朗日量提供,该手征拉格朗日量由QCD推导出,并且不包含拟合参数。结果表明,$0^+$和${1^+}'$态的质量有很强的下移,而${1^+}"$和$2^+$态几乎保持静止.有两个因素对大的质量位移是必不可少的:$0^+$和$1^{+'}$态与$S$波衰变通道的强耦合,其中包含一个南武-戈德斯通介子,以及由于两个重-轻介子的双旋量结构而产生的手征翻转跃迁。预测了$M(B^*_s(0^+))=5710(15)$ MeV和$M(B_s(1^{+'}))=5730(15)$ MeV的质量。对宽度$Γ(D_{s1}(2536))<2.3$ MeV的实验限制对$1^+$和$1^{+'}$状态之间的可容许混合角施加了强限制。

英文摘要:

In the framework of the coupled channel model the mass shifts of the $P$--wave excitations of $D_s$ and $B_s$ mesons have been calculated. The corresponding coupling to $DK$ and $BK$ channels is provided by the effective chiral Lagrangian which is deduced from QCD and does not contain fitting parameters. The strong mass shifts down for $0^+$ and ${1^+}'$ states have been obtained, while ${1^+}"$ and $2^+$ states remain almost at rest. Two factors are essential for large mass shifts: strong coupling of the $0^+$ and $1^{+'}$ states to the $S$-wave decay channel, containing a Nambu-Goldstone meson, and the chiral flip transitions due to the bispinor structure of both heavy-light mesons. The masses $M(B^*_s(0^+))=5710(15)$ MeV and $M(B_s(1^{+'}))=5730(15)$ MeV are predicted. Experimental limit on the width $Γ(D_{s1}(2536))<2.3$ MeV puts strong restrictions on admittable mixing angle between the $1^+$ and $1^{+'}$ states.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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