Half-BPS Janus solutions in AdS₇

We study half-BPS flows in gauged minimal 7d supergravity featured by an AdS₃ × S³ slicing of the metric, supported by a dyonic three-form field. We first present a novel strategy for analytic integration of the BPS equations, which makes use of the integrals of motion. Subsequently, we discuss the suitable choice of integration constants that gives rise to smooth geometries. These flows are asymptotically locally AdS₇ and close off smoothly reproducing an AdS₃ × ℝ⁴ geometry. We then discuss their uplifts to 11d and massive IIA supergravity and observe that they describe one-parameter deformations of their AdS₇ × S⁴ and AdS₇ × S³ vacua, respectively, their holographic interpretation being as conformal defect CFT₂’s within the corresponding dual SCFT₆’s. We conclude with the computation of the holographic central charge, by focussing on the M-theory interpretation.