$X(3872)$ as a four-quark state in a Dyson-Schwinger/Bethe-Salpeter approach

Paul C. Wallbott, Gernot Eichmann, Christian S. Fischer

We generalise the framework of Dyson-Schwinger and Bethe-Salpeter equations for four-quark states to accommodate the case of unequal quark masses. As a first application, we consid…