论文标题
三角机构在$λ_b\rightarrowλ_cπ^-f_0（980）$反应中的角色
Role of the triangle mechanism in the $Λ_b\rightarrow Λ_cπ^-f_0(980)$ reaction
论文作者
论文摘要
我们通过$ k^{*0} k^-k^-k^-k^+$ and $ f_0（980）$衰减研究$λ_b\toλ_cπ^-f_0（980）$生产，$ f_0（980）$衰减到$π^+π^ - $中，这些环在$π^-f_0（980）$不变质量分布中产生的峰值约为1.42 GEV，这与解释$ a_1（1420）$ peak的质量分布相同。在通过修复$π^-f_0（980）$不变质量获得的$π^+π^ - $分布中，可以看到$ f_0（980）$的明显峰，以及$π^-f_0（980）$的峰值分布在$ m_ {π^-f_0} $ ggre上，该峰值在$ m_ {π^-f_0} = 1.42 = 1.42 = 1.42 = 1.42 = 1.42 = 1.42 = 1.42 = 1.42。 $ k^*\ bar kk $ loop。 $λ_b\rightArrowλ_cπ^-f_0（980）$的分支率为$ f_0（980）\rightArrowπ^+π^ - 通过三角形机制获得，通过集成$π^-f_0（980）$从1到1.6 GEV分配来获得，从1到1.6 GEV估计$ 10^$ 10^ - 4 $λ_b\toλ_cπ^-f_0（980）$分支比率和$π^-f_0（980）$不变质量分布的未来测量值将提供进一步的线索，以阐明$ A_1（1420）$ peacs的进一步线索。
We investigate the $Λ_b\toΛ_cπ^-f_0(980)$ production with a $f_0(980)$ decay into $π^+π^-$ via the $K^{*0}K^-K^+$ and $K^{*-}K^0\bar{K}^0$ triangle loops. These loops produce a peak around 1.42 GeV in the $π^-f_0(980)$ invariant mass distribution, which is the same mechanism as the one considered to explain the $a_1(1420)$ peak. In the $π^+π^-$ distribution obtained by fixing the $π^-f_0(980)$ invariant mass to some values, a clear peak of $f_0(980)$ is seen, and the $π^-f_0(980)$ distribution has a peak around $M_{π^-f_0}=1.42$ GeV, which is caused by the triangle mechanism of the $K^*\bar KK$ loop. The branching ratio of $Λ_b\rightarrowΛ_cπ^-f_0(980)$ with $f_0(980)\rightarrowπ^+π^-$ by the triangle mechanism, obtained by integrating the $π^-f_0(980)$ distribution from 1 to 1.6 GeV, is estimated to be the order $10^{-4}$. Future measurements of the $Λ_b\toΛ_cπ^-f_0(980)$ branching ratio and the $π^-f_0(980)$ invariant mass distribution predicted in this work would give further clues to clarify the nature of the $a_1(1420)$ peak.
