Classification of Abe-Tange's ribbon knots

Abe and Tange constructed a sequence of slice disks with the same exterior. Moreover, they showed that these slice disks are ribbon disks. We call the boundaries of the ribbon disks Abe-Tange's ribbon knots. In this paper, we classify Abe-Tange's ribbon knots completely by the Γ-polynomial. Therefore, we see that all ribbon disks in the sequence are mutually inequivalent.