Convex hull of a quarter of an annulus

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I just learned about convex hulls and want to confirm I understood it correctly.

Find the convex hull of $$D= \{ (x,y)\in \mathbb R^2 : x,y \geq 0, 1 \leq x^2 + y^2 \leq 4 \}$$

Am I correct that its convex hull is the following?

$$\mbox{conv} (D) = \{(x,y)\in \mathbb R^2: x,y \geq 0, x + y \geq 1, x^2 + y^2 \leq 4\}$$

What is the appropriate notation for the set representing the convex hull?