The static three-quark(3Q) potential is investigated in the SU(3) lattice QCD at the quenched level, using the standard Wilson action with $\beta =5.7 (a\simeq 0.2{ \rm fm})$ and $12^3\times 24$. With the 3Q Wilson loop, the ground-state 3Q potential $V_{ \rm 3Q}$ is calculated for 16 patterns of the 3Q configuration, using the smearing technique, which enhances the ground-state overlap of the 3Q operator. With the accuracy better than a few %, the lattice QCD data for $V_{ \rm 3Q}$ are well described by a sum of the Coulomb term, a constant and the linear term which is proportional to the minimal length $L_{ \rm min}$ of the flux-tube linking the 3 quarks. Our results seem to support the Y-type flux picture rather than $\Delta$-type one. From the comparison of $V_{ \rm 3Q}$ with the ${ \rm Q}$-${ \rm \bar{ Q}}$ potential, we find the universality of the string tension, $\sigma_{ \rm 3Q}\simeq \sigma_{ \rm Q\bar{ Q}}$ as well as the OGE relation on the Coulomb coefficient, $A_{ \rm 3Q}\simeq { 1/2}A_{ \rm Q\bar{ Q}}$.
Categories: hep-lat