JOG thickness predicted by ANGE and OC. In (a), a uniform molar volume corresponding to that of Cs₂ MoO₄ at room temperature has been assumed for all fission products. In (b) and (c) the gap composition has been evaluated thermodynamically at 800 K (b), and 1000 K (c). In Tourasse (red dots) [1], the burnup values refer to the local burnup at which the JOG was measured. In Melis (black dots) [8], the burnup refers to the maximum burnup reached in the fuel pin.