论文标题
如果存在LHCB Pentaquark的存在，则可以从其在阈值附近的核中研究中等内部修饰$ j/ψ$介体的中等修饰。
The possibility to study in-medium modification of $J/ψ$ mesons from their photoproduction on nuclei near threshold in the case of presence of the LHCb pentaquark states $P^+_c$ in this photoproduction
论文作者
论文摘要
我们通过考虑不连贯的直接（$γn\ to {j/ψ} n $）和两步性（$γp\ f iNCOM，$γn\ to p^+q^+_ c（4312）$ p^+p^+p^+p^+p^+p^+p^+p^+p^4312） {j/ψ} p $; $γp\ to p^+_ c（4440）$，$ p^+_ C（4440）\ to {j/ψ}我们计算了$ j/ψ$中的非谐振和共振产生的绝对激发功能，$^{12} $ c和$^{208} $ pb target核心在不同的场景中，用于直接变化的$ j/ψ$ mesons和deceays $ p^+p^+c（43） {j/ψ} p $，$ p^+_ C（4440）\ to {j/ψ} p $和$ p^+_ c（4457）\ to {j/ψ} p $。我们表明，$γa$反应中的非共振子阈值$ j/ψ$生产表明，对于$ j/ψ$梅森的使用中的内部修改场景有些敏感，仅在上面的分支比率较低的情况下，该$ j/ψ$ erson并未被共鸣产生的$ j/ψ$ erson所掩盖。 We also demonstrate that if these branching ratios more than 5\% then the presence of the $P^+_c(4312)$, $P^+_c(4440)$ and $P^+_c(4457)$ resonances in $J/ψ$ photoproduction on nuclei produces above threshold additional enhancements in the behavior of the total $J/ψ$ creation cross section on nuclei, which could be在未来的JLAB实验中还研究了CEBAF设施的实验，以提供其存在的进一步证据，也可以提供有关其性质的宝贵信息。
We study the $J/ψ$ photoproduction from nuclei in the near-threshold beam energy region of $E_γ$=5--11 GeV within the nuclear spectral function approach by considering incoherent direct ($γN \to {J/ψ}N$) and two-step ($γp \to P^+_c(4312)$, $P^+_c(4312) \to {J/ψ}p$; $γp \to P^+_c(4440)$, $P^+_c(4440) \to {J/ψ}p$; $γp \to P^+_c(4457)$, $P^+_c(4457) \to {J/ψ}p$) $J/ψ$ production processes. We calculate the absolute excitation functions for the non-resonant and resonant production of $J/ψ$ mesons off $^{12}$C and $^{208}$Pb target nuclei within the different scenarios for in-medium modification of the directly photoproduced $J/ψ$ mesons and for branching ratios of the decays $P^+_c(4312) \to {J/ψ}p$, $P^+_c(4440) \to {J/ψ}p$ and $P^+_c(4457) \to {J/ψ}p$. We show that the non-resonant subthreshold $J/ψ$ production in $γA$ reactions reveals some sensitivity to employed in-medium modification scenarios for $J/ψ$ mesons, which is not masked by the resonantly produced $J/ψ$ mesons, only if above branching ratios are less than 5\%. We also demonstrate that if these branching ratios more than 5\% then the presence of the $P^+_c(4312)$, $P^+_c(4440)$ and $P^+_c(4457)$ resonances in $J/ψ$ photoproduction on nuclei produces above threshold additional enhancements in the behavior of the total $J/ψ$ creation cross section on nuclei, which could be also studied in the future JLab experiments at the CEBAF facility to provide both further evidence for their existence and valuable information on their nature.
