Author(s): , ,
Institution(s): 1. Centro de Astrobiologia, 2. European Space Agency
We present the preliminary results of a Herschel/PACS Spectroscopy study of a large sample of proto-planetary and planetary nebulae displaying a wide variety of dust and gas chemical properties at optical and near- to mid-infrared wavelengths. The goal of this study is to explore the far infrared properties of evolved stars with different chemical composition and establish connections with their observational properties at other wavelengths as a function of their mass and evolutionary stage. The complementary information obtained at Herschel/PACS wavelengths is used to advance on the understanding of the physical and chemical processes which take place in these stars at the end of their evolution and to determine their contribution to the chemical evolution of the ISM in different metallicity environments.