The existence and asymptotic behaviours of normalized solutions for critical fractional Schrödinger equation with Choquard term

In this paper, we consider the existence and asymptotic behaviours of solutions for following fractional equation$ \begin{align*} (-\Delta)^{s}u+\lambda u = \mu(I_{\alpha}\star|u|^p)|u|^{p-2}u+|u|^{2_{s}^{*}-2}u, \quad x\in \mathbb{R}^N, \end{align*} $under constraint$ \int_{\mathbb{R}^N}|u|^2dx c^2, $where $ N\ge2, \; I_{\alpha} \frac{1}{|x|^{N-\alpha}}, \alpha\in(N-2s, N), 2\le p<1+\frac{\alpha+2s}{N} 2_{s}^{*} \frac{2N}{N-2s} $.