Asymptotic Behavior for a Nonlocal Diffusion Equation with Absorption and Nonintegrable Initial Data. the Supercritical Case

In this paper we study the asymptotic behavior as time goes to infinity of the solution to a nonlocal diffusion equation with absorption modeled by a powerlike reaction $-u^p$, $p>1$ and set in ${\mathbb{R}}^N$. We consider a bounded, nonnegative initial datum $u_0$ that behaves like a negative power at infinity. That is, $\mathrm{\mid }x{\mathrm{\mid }}^{\alpha }{u}_0(x)\to A>0$ as $\mathrm{\mid }x\mathrm{\mid }\to \mathrm{\infty }$ with $0<\alpha \le N$. We prove that, in the supercritical case $p>1+2\mathrm{/}\alpha$, the solution behaves asymptotically as that of the heat equation --with diffusivity $\text{a}$ related to the nonlocal operator-- with the same initial datum.