Chiral algebras from \Omega-deformation

Understand

In the presence of an $\Omega$-deformation, local operators generate a chiral algebra in the topological-holomorphic twist of a four-dimensional $\mathcal{N} = 2$ supersymmetric field theory.

• We show that for a unitary $\mathcal{N} = 2$ superconformal field theory, the chiral algebra thus defined is isomorphic to the one introduced by Beem et al.
• Our definition of the chiral algebra covers nonconformal theories with insertions of suitable surface defects.