Cucker-Smale model with time delay

We study the flocking model for continuous time introduced by Cucker and Smale adding a positive time delay \begin{document}$ \tau $\end{document} . The goal of this article is to prove that the same unconditional flocking result for the non-delayed case is valid in the delayed case. A novelty is that we do not need to impose any restriction on the size of \begin{document}$ \tau $\end{document} . Furthermore, when the unconditional flocking occurs, velocities converge exponentially fast to a common one.