Right-handed sneutrinos as self-interacting dark matter in supersymmetric economical 3-3-1 model

In this work we show that the supersymmetric economical SU(3)_C X SU(3)_L X U(1)_X (3-3-1) gauge model has a realistic candidate for self-interacting dark matter. In the model under consideration, the right-handed sneutrino is in bottom of the triplet, which is a singlet of the Standard Model SU(2)_L group. In addition, the right-handed sneutrino is the lightest slepton. By these properties, the right-handed sneutrino is weakly interacting with the Standard Model and stable without introduction of extra symmetry. From the Spergel-Steinhardt condition, the typical mass limit $\leq 10 $ MeV is derived. With self-interacting coupling constant fixed by supersymmetry, this limit is deduced without any approximation. The condition for thermal generated self-interacting dark matter in the Universe is also obtained.