The affine closure of cotangent bundles of horospherical spaces

Baohua Fu, Jie Liu

For a smooth quasi-affine variety $X$, the affine closure $\overline{T^{\ast }X}:=\text{Spec}(\mathbb{K}[T^{\ast }X])$ contains $T^{\ast }X$ as an open subset, and its smooth locus carries a sympl…