In the context of integrated correlators in N=4 SYM, we study the
2-point functions of local operators with a superconformal line defect.
Starting from the mass-deformed N=2β theory in presence of a
21β-BPS Wilson line, we exploit the residual superconformal symmetry
after the defect insertion, and show that the massive deformation corresponds
to integrated insertions of the superconformal primaries belonging to the
stress tensor multiplet with a specific integration measure which is explicitly
derived after enforcing the superconformal Ward identities. Finally, we show
how the Wilson line integrated correlator can be computed by the
N=2β Wilson loop vacuum expectation value on a 4-sphere in terms
of a matrix model using supersymmetric localization. In particular, we
reformulate previous matrix model computations by making use of recursion
relations and Bessel kernels, providing a direct link with more general
localization computations in N=2 theories.Comment: 34 pages, 1 figur