The Optimal Convergence Rates for the Multi-dimensional Chemotaxis Model in Critical Besov Spaces

In this paper, we are concerned with the Cauchy problem to the multi-dimensional (N≥4\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$N\geq4$\end{document}) chemotaxis model. We prove the optimal convergence rates of the strong solutions to the system for initial data close to a stable equilibrium state in critical Besov spaces. Our main ideas are based on the low-high frequency decomposition and the smooth effect of dissipative operator.