Types of gauge groups in six-dimensional F-theory on double covers of rational elliptic 3-folds

In this paper, we analyze gauge groups in six-dimensional [Formula: see text] F-theory models. We construct elliptic Calabi–Yau 3-folds possessing various singularity types as double covers of “1/2 3-folds,” a class rational 3-folds, by applying the method discussed previous study to classify 1/2 3-folds. One three U(1) factors are formed on constructed The corresponding non-Abelian group deduced. work consist text]- and text]-type singularities.