$\bf\Lambda _{\bf c} \textbf{(2880)}^{\bf +} \textbf{2}$D波激发态的强衰变

doi:10.12066/j.issn.1007-2861.2324

摘要/Abstract

摘要：

在$^3P_0 $模型框架下, 计算$\Lambda _{c} (2880)^+$作为2D波激发态的衰变宽度和分支比, 确定其量子态并探究内部激发模式. 计算结果表明: $\Lambda _{c} (2880)^+$有可能是2D激发态$\Lambda _{{c}2} \big(\frac{3}{2}^+\big)$, $J^P=\frac{3}{2}^+$, 且$n_\rho =1$、$l_\lambda =2$, 为径向$\rho $激发、轨道$\lambda $激发的激发模式, 总衰变宽度${\it\Gamma}_{total} =18.53$ MeV, 分支比比值$R={\it\Gamma}(\Lambda _{c}(2880)^+\to \Sigma _{c}(2520)\pi)$/${\it\Gamma}(\Lambda _{c} (2880)^+\to \Sigma _{c} (2455)\pi)=0.16$; 也可能是2D激发态$\Lambda _{{c}2}^{'}\big(\frac{3}{2}^+\big)$, $J^P=\frac{3}{2}^+$, 且$n_\lambda =1$、$l_\lambda =2$, 为径向$\lambda $激发、轨道$\lambda $激发的激发模式, 总衰变宽度${\it\Gamma} _{total} =1.69$ MeV, 分支比比值$R={\it\Gamma}(\Lambda _{c} (2880)^+\to \Sigma_{c}(2520)\pi )$/${\it\Gamma} (\Lambda_{c} (2880)^+\to \Sigma_{c}(2455)\pi )=0.10$.

关键词: $^3P_0 $ 模型, 强衰变, 衰变宽度, 分支比比值

Abstract:

The strong decay of $\Lambda _{c} (2880)^+$ in the $^3P_0 $model was investigated. The decay widths and the ratio of branchingfractions of $\Lambda _{c} (2880)^+$ were calculated. Thenumerical results showed that $\Lambda _{c} (2880)^+$ may be a2D-excited $\Lambda _{{c}2}\big(\frac{3}{2}^+\big)$ with$J^P\!=\!\frac{3}{2}^+$. $n_\rho \!=\!1$ and $l_\lambda\!=\!2$belonged to the radial $\rho $-mode excitation and the orbital$\lambda $-mode excitation, respectively. The ratio of branchingfractions was $R={\it\Gamma} (\Lambda _{c} (2880)^+\to \Sigma_{c} (2520)\pi )$/${\it\Gamma} (\Lambda _{c} (2880)^+\to\Sigma _{c} (2455)\pi )=0.16$. The total decay width was${\it\Gamma} _{total} = 18.53$ MeV. $\Lambda _{c} (2880)^+$could also be a 2D-excited $\Lambda _{{c}2}^{'}\big(\frac{3}{2}^+\big)$ with $J^P=\frac{3}{2}^+$,$n_\lambda =1$ and $l_\lambda=2$, indicating the radial $\lambda$-mode excitation and the orbital $\lambda $-mode excitation. Inthis study, ${\it\Gamma} _{total} =1.69$ MeV, and $R={\it\Gamma}(\Lambda _{c} (2880)^+\to \Sigma _{c} (2520)\pi)$/${\it\Gamma} (\Lambda _{c} (2880)^+\to \Sigma _{c}(2455)\pi )=0.10$.

Key words: $^3P_0 $ model, strong decay, decay width, ratio of branching fractions

中图分类号:

O413

李阳, 张爱林. $\bf\Lambda _{\bf c} \textbf{(2880)}^{\bf +} \textbf{2}$D波激发态的强衰变[J]. 上海大学学报(自然科学版), 2022, 28(2): 347-356.

LI Yang, ZHANG Ailin. Strong decay of ${\Lambda}_{\bf c}\textbf{(2880)}^{+}$ as 2D-wave excitations[J]. Journal of Shanghai University（Natural Science Edition）, 2022, 28(2): 347-356.

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