Let $C$ be an hyperelliptic curve of genus $g$ and let $f:C\rightarrow \mathbb{P}^1$ be the corresponding 2 to 1 covering ramified in $2g+2$ points.
Let $L$ be a line bundle on $C$ such that either $L^{\otimes 2} = \mathcal{O}_C$ or $L^{\otimes 2} = \mathcal{\omega}_C^{\otimes 2}$. Can we find a line bundle $A$ on $\mathbb{P}^1$ such that $f^{*}A = L$.
Any suggestions or references will be most helpful.