Branes wrapped on orbifolds and their gravitational blocks

We construct newsupersymmetric AdS(2) x M4 solutions of D = 6 gauged supergravity, where M4 are certain four-dimensional orbifolds. After uplifting to massive type IIA supergravity these correspond to the near-horizon limit of a system of N D4-branes and N f D8-branes wrapped on M4. In one class of solutions, M4 = Sigma_g x Sigma is a spindle fibered over a smooth Riemann surface of genus g > 1, while in another class M4 = Sigma x Sigma is a spindle fibered over another spindle. Both classes can be thought of as orbifold generalizations of Hirzebruch surfaces and, in the second case, we describe the solutions in terms of toric geometry. We show that the entropy associated with these solutions is reproduced by extremizing an entropy function obtained by gluing gravitational blocks, using a general recipe for orbifolds that we propose. We also discuss how our prescription can be used to define an off-shell central charge whose extremization reproduces the gravitational central charge of analogous AdS3 x M4 solutions of D = 7 gauged supergravity, arising from wrapping M5-branes on M4.