I-ball formation with logarithmic potential
  A coherently oscillating real scalar field with potential shallower than
quadratic one fragments into spherical objects called I-balls. We study the
I-ball formation for logarithmic potential which appears in many cosmological
models. We perform lattice simulations and find that the I-balls are formed
when the potential becomes dominated by the quadratic term. Furthermore, we
estimate the I-ball profile assuming that the adiabatic invariant is conserved
during formation and obtain the result that agrees to the numerical
simulations.
