Closed inflationary universe with tachyonic field

In this article we study closed inflationary universe models by using a tachyonic field theory. We determine and characterize the existence of a universe which has Ω>1 and which describes a period of inflation. We find that the considered models are less restrictive compared to the standard ones with a scalar field. We use recent astronomical observations to constrain the parameters appearing in the model. The results obtained are compared to those found in the standard scalar field inflationary universes. (orig.)