9. Point $P$ is a moving point on circle $C:(x+2)^{2}+y^{2}=4$, and it is not at the origin. The fixed point $A$ has coordinates $(2,0)$. The perpendicular bisector of line segment $AP$ intersects line $CP$ at point $Q$. Let $M(-1,0), N(1,0)$, then the product of the slopes of lines $MQ$ and $NQ$ is $\qquad$.
Given, $|Q C|-|Q A|=2 \Rightarrow$ the locus of point $Q$ is the right branch of a hyperbola with foci at $A, C$ and a real axis length of 2, the equation of the locus is $x^{2}-\frac{y^{2}}{3}=1(x>1)$.
Therefore, $k_{Q M} \cdot k_{Q N}=\frac{y_{Q}^{2}}{x_{Q}^{2}-1}=3$.