Spin 2 fluctuations in 1/4 BPS AdS 3 /CFT 2

In this paper we study spin 2 fluctuations around a warped AdS3 × S2 × T4 × $$ {\mathcal{I}}_{\rho } $$ background in type IIA supergravity with small $$ \mathcal{N} $$ = (0, 4) supersymmetry. We find a class of fluctuations, which will be called universal, that is independent of the background data and corresponds to operators with scaling dimension Δ = 2l + 2, being l the angular-momentum-quantum-number on the S2 which realises the SU(2)R symmetry. We compute the central charge for $$ \mathcal{N} $$ = (0, 4) two-dimensional superconformal theories from the action of the spin 2 fluctuations.