Probing Nucleon-$Ω_{\rm ccc}$Interaction via Lattice QCD at Physical Quark Masses
Liang Zhang, Takumi Doi, Yan Lyu, Tetsuo Hatsuda, Yu-Gang Ma
TL;DR
This paper investigates the N-Ωccc interaction in the $^3S_1$ and $^5S_2$ channels using (2+1)-flavor lattice QCD at physical quark masses, extracting the interaction potential via the time-dependent HAL QCD method. It finds attractive interactions in both channels but no bound state, with a dominant spin-independent potential $V_0(r)$ and a short-range spin-dependent term $V_s(r)$, and it quantifies the low-energy scattering parameters $a_0$ and $r_{eff}$ from the effective-range expansion. The results are discussed in the context of heavy-hadron chromo-polarizability by comparing to N-J/psi and N-Ωsss systems, and the charm-mass dependence is explored, showing a weaker $V_0$ for heavier charm mass consistent with roughly $1/m_{Ω_{3c}}$ scaling. These findings provide first-principles constraints on heavy-baryon interactions relevant for hadron spectroscopy and heavy-ion phenomenology.
Abstract
We study the S-wave interactions between the nucleon ($N$) and the triply charmed Omega baryon ($Ω_{\mathrm{ccc}}$) using (2+1)-flavor lattice QCD with a physical pion mass ($m_π\simeq 137.1$ MeV) on a lattice volume $\simeq (8.1~\mathrm{fm})^3$. The charm quark is implemented with a relativistic heavy-quark action at its physical mass. Employing the time-dependent HAL QCD method, the $N$-$Ω_{\mathrm{ccc}}$ potentials in the spin-1 ($^3\mathrm{S}_1$) and spin-2 ($^5\mathrm{S}_2$) channels are extracted. In both channels, overall attraction is found with the scattering parameters, $a_0 = 0.56(0.13)\left(^{+0.26}_{-0.03}\right)$ fm and $r_{\mathrm{eff}} = 1.60(0.05)\left(^{+0.04}_{-0.12}\right)$ fm for the $^3\mathrm{S}_1$ channel, and $a_0 = 0.38(0.12)\left(^{+0.25}_{-0.00}\right)$ fm and $r_{\mathrm{eff}} = 2.04(0.10)\left(^{+0.03}_{-0.22}\right)$ fm for the $^5\mathrm{S}_2$ channel, indicating the absence of a dibaryon bound state. The extracted potentials are further decomposed into spin-independent and spin-dependent components. The spin-independent potential is a dominant component and features a short-range attractive core and a long-range attractive tail, while the spin-dependent potential shows short-range attraction (repulsion) in the spin-1 (spin-2) channel. Qualitative comparisons with previous studies of the $N$-$J/ψ$ and $N$-$Ω_{\rm{sss}}$ systems at $m_π\simeq 146$ MeV are provided, emphasizing the role of heavy-hadron chromo-polarizability arising from soft-gluon exchange between the nucleon and flavor-singlet hadrons. The charm quark mass dependence of the $N$-$Ω_{\rm ccc}$ potential is investigated as well.
