Lemma 59.51.6. Let f: X\to Y be a morphism of schemes and \mathcal{F}\in \textit{Ab}(X_{\acute{e}tale}). Then R^ pf_*\mathcal{F} is the sheaf associated to the presheaf
(V \to Y) \longmapsto H_{\acute{e}tale}^ p(X \times _ Y V, \mathcal{F}|_{X \times _ Y V}).
More generally, for K \in D(X_{\acute{e}tale}) we have that R^ pf_*K is the sheaf associated to the presheaf
(V \to Y) \longmapsto H_{\acute{e}tale}^ p(X \times _ Y V, K|_{X \times _ Y V}).
Proof.
This lemma is valid for topological spaces, and the proof in this case is the same. See Cohomology on Sites, Lemma 21.7.4 for the case of a sheaf and see Cohomology on Sites, Lemma 21.20.3 for the case of a complex of abelian sheaves.
\square
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