López Maroto, Antonio2023-06-202023-06-2020000920-563210.1016/S0920-5632(99)00896-8https://hdl.handle.net/20.500.14352/59331International Workshop on Particles in Astrophysics and Cosmology (1999. Valencia). © 2014 Elsevier B.V. I thank A. Mazumdar for useful discussions. This work has been supported by SEUID-Royal Society and CICYT-AEN97-1693 (Spain).We study the production of gravitinos during the preheating era after inflation by means of the non-perturbative Bogolyubov technique. Considering only the helicity ±3/2 states, the problem is reduced to the simpler Dirac fermions case. We calculate the production in a particular supergravity model in an expanding universe and obtain the spectrum and number density. Finally we compare the results with the nucleosynthesis bounds and extract some consequences.engjournal articlehttp://dx.doi.org/10.1016/S0920-5632(99)00896-8http://www.sciencedirect.com/http://arxiv.org/abs/hep-ph/9906388open access53Big-bang nucleosynthesisInflationFermionsSupersymmetrySupergravityUniversePhysicsFísica (Física)22 Física