Global existence and Blow-up for the 1D damped compressible Euler equations with time and space dependent perturbation

In this paper, we consider the 1D Euler equation with time and space dependent damping term $-a(t,x)v$. It has long been known that when $a(t,x)$ is a positive constant or 0, the solution exists globally in time or blows up in finite time, respectively. In this paper, we prove that those results are invariant with respect to time and space dependent perturbations. We suppose that the coefficient $a$ satisfies the following condition $|a(t,x)-{\mu }_0|\le a_1\left(t\right)+a_2\left(x\right),$where ${\mu }_0\ge 0$ and $a_1$ and $a_2$ are integrable functions with $t$ and $x$. Under this condition, we show the global existence and the blow-up with small initial data, when ${\mu }_0>0$ and ${\mu }_0=0$ respectively. The key of the proof is to divide space into time-dependent regions, using characteristic curves.