  In quenched QCD, where the dynamic creation of quark-antiquark pairs out of
the vacuum is neglected, a confined baryonic system composed of three static
quarks exhibits string-like behaviour at large interquark separation, with the
formation of flux tubes characterized by the geometry of the so-called Y
ansatz. We study the fluctuations of the junction of the three flux tubes,
assuming the dynamics to be governed by an effective bosonic string model. We
show that the asymptotic behaviour of the effective width of the junction grows
logarithmically with the distance between the sources, with the coefficient
depending on the number of joining strings, on the dimension of spacetime and
on the string tension.
