Higher order asymptotic expansions for the convection-diffusion equation in the Fujita-subcritical case

This paper is devoted to the asymptotic behavior of global solutions to the convection-diffusion equation in the Fujita-subcritical case. We improve the result by Zuazua (1993) and establish higher order asymptotic expansions with decay estimates of the remainders. We also discuss the optimality for the decay rates of the remainders.