Strong Decays of observed $Λ_c$ Baryons in the $^3P_0$ Model

Abstract

The strong decay widths and some important branching ratios of possible Okubo-Zweig-Iizuka(OZI)-allowed strong decay channels of $Λ_c(2595)^+$, $Λ_c(2625)^+$, $Λ_c(2765)^+$ ($Σ_c(2765)^+$), $Λ_c(2860)^+$, $Λ_c(2880)^+$ and $Λ_c(2940)^+$ are computed in a $^{3}P_{0}$ model, and possible assignments of these $Λ_c$ are given. (1), $Λ_c(2595)^+$ and $Λ_c(2625)^+$ are possibly the $1P$-wave charmed baryons $Λ_{c1}(\frac{1}{2}^-)$ and $Λ_{c1}(\frac{3}{2}^-)$, respectively. (2), $Λ_c(2765)^+$ ($Σ_c(2765)^+$) seems impossibly the $1P$-wave $Λ_{c}$, it could be the $2S$-wave or $1D$-wave charmed baryon. So far, the experimental information has not been sufficient for its identification. (3), $Λ_c(2860)^+$ seems impossibly $2S$-wave charmed baryon, it may be the $P$-wave $\tildeΛ_{c2}^{ }(\frac{3}{2}^-)$ or $\tildeΛ_{c2}^{ }(\frac{5}{2}^-)$, it could also be the $D$-wave $\checkΛ_{c1}^{2}(\frac{1}{2}^+)$ or $\checkΛ_{c1}^{2}(\frac{3}{2}^+)$. If the hypothesis that $Λ_c(2860)^+$ has $J^P={3\over 2}^+$ is true, $Λ_c(2860)^+$ is possibly the $D$-wave $\checkΛ_{c1}^{2}(\frac{3}{2}^+)$ which has a predicted branching ratio $R=Γ(Σ_c(2520)π)/Γ(Σ_c(2455)π)=2.8$. (4), $Λ_c(2880)^+$ is impossibly a $1P$-wave or $2S$-wave charmed baryon, it may be a $D$-wave $\checkΛ_{c3}^{2}(\frac{5}{2}^+)$ with $Γ_{total}=1.3$ MeV. The predicted branching ratio $R=Γ(Σ_c(2520)π)/Γ(Σ_c(2455)π)=0.35$, which is consistent with experiment. (5), $Λ_c(2940)^+$ is the $P$-wave $\tildeΛ_{c2}^{ }(\frac{3}{2}^-)$ or $\tildeΛ_{c2}^{ }(\frac{5}{2}^-)$, it is also possibly the $D$-wave $\checkΛ_{c3}^{2}(\frac{5}{2}^+)$ or $\checkΛ_{c3}^{2}(\frac{7}{2}^+)$.

13 pages, 2 figures, 17 tables, RevTex