Spontaneous SUSY breaking without R symmetry in supergravity

Abstract

We discuss spontaneous supersymmetry (SUSY) breaking in a model with an anomalous U(1)A symmetry. In this model, the size of the each term in the superpotential is controlled by the U(1)A charge assignment and SUSY is spontaneously broken via the Fayet-Iliopoulos of U(1)A at the metastable vacuum. In the global SUSY analysis, the gaugino masses become much smaller than the sfermion masses, because an approximate R symmetry appears at the SUSY breaking vacuum. In this paper, we show that gaugino masses can be as large as gravitino mass, taking the supergravity effect into consideration. This is because the R symmetry is not imposed so that the constant term in the superpotential, which is irrelevant to the global SUSY analysis, largely contributes to the soft SUSY breaking terms in the supergravity. As the mediation mechanism, we introduce the contributions of the field not charged under U(1)A and the moduli field to cancel the anomaly of U(1)A. We comment on the application of our SUSY breaking scenario to the grand unified theory.