Two particle hidden sector and astronomical sources as ALP-telescopes

In the first part of the talk I will introduce a model for the dark sector that contains axion-like particles and hidden photons. In this model, both particles can couple to
photons. We provide bounds for the couplings versus the mass, using current results from ALPS-I and PVLAS. In the second part of the talk I will briefly discuss the advantages of using astronomical sources as ALP-telescopes in comparison to terrestrial experiments.