The purpose of this paper is to study the asymptotic behavior of the positive
solutions of the problem ∂tu−Δu=au−b(x)upinΩ×R+,u(0)=u0,u(t)∣∂Ω=0 as p→+∞,
where Ω is a bounded domain and b(x) is a nonnegative function. We
deduce that the limiting configuration solves a parabolic obstacle problem, and
afterwards we fully describe its long time behavior.Comment: 15 page