9. Given $A=\left\{x \mid x^{2}-4 x+3<0, x \in \mathbf{R}\right\}, B=\left\{x \mid 2^{1-x}+a \leqslant 0, x^{2}-2(a+7) x+5 \leqslant 0\right.$, $x \in \mathbf{R}\}$. If $A \subset B$, then the range of real number $a$ is
According to the problem, $A=(1,3)$. Then 
\[
\left\{\begin{array}{l}
a \leqslant-2^{1-x}, \\
1-2(a+7)+5 \leqslant 0, \\
9-6(a+7)+5 \leqslant 0
\end{array} \Rightarrow\left\{\begin{array}{l}
a \leqslant-1, \\
a \geqslant-4, \\
a \geqslant-\frac{14}{3}
\end{array} \Rightarrow a \in[-4,-1]\right.\right.
\]