de Carvalho Braga, DenisFernandes da Fonseca, AlexanderGonçalves, Luiz Fernando [UNESP]Mello, Luis Fernando2020-12-122020-12-122020-04-01Journal of Mathematical Analysis and Applications, v. 484, n. 1, 2020.1096-08130022-247Xhttp://hdl.handle.net/11449/198256We study the stability of an invisible fold-fold singularity of planar piecewise smooth Hamiltonian vector fields by computing some kind of Lyapunov coefficients. We obtain the general expressions for the first five Lyapunov coefficients. As a consequence, the bifurcation diagrams, illustrating the number, types and positions of the bifurcating small amplitude crossing limit cycles for these vector fields, are determined.engBifurcationFold-fold singularityHamiltonian vector fieldLimit cyclePiecewise smooth vector fieldArtigo10.1016/j.jmaa.2019.1236922-s2.0-85076222955