Weak solutions of semilinear elliptic equation involving Dirac mass

In this paper, we study the following elliptic problem with Dirac mass \begin{equation}\label{eq 0.1} -\Delta u=Vu^p+k \delta_0\quad {\rm in}\quad \mathbb{R}^N, \qquad \lim_{|x|\to+\infty}u(x)=0, \end{equation} where $N>2$, $p>0$, $k>0$, $\delta_0$ is Dirac mass at the origin, the function $V$ is a locally Lipchitz continuous in $\mathbb{R}^N\setminus\{0\}$ satisfying $$V(x)\le \frac{c_1}{|x|^{a_0}(1+|x|^{a_\infty-a_0})}$$ with $a_0<N,\ a_\infty>a_0$ and $c_1>0$. We obtain two positive solutions of (\ref{eq 0.1}) with additional conditions for parameters on $a_\infty, a_0$, $p$ and $k$. The first solution is a minimal positive solution and the second solution is constructed by Mountain Pass theorem.