Figure 6

Existence of codimension two and three bifurcation points in Stiefel model (27) with the parameter values given in Table 4. (a) The conditions given by equations (6), (7) and (20) are plotted in the V, \(g_{M}\) space. The two intersection points (red dots) of the conditions in Theorem 3.1 show that there are two BT points in the model. The one intersection point (green dot) of the conditions in Theorem 3.2 shows the existence of one cusp point; (b) The three conditions are plotted when the leak conductance is increased to \(g_{L}=0.3785\). The intersection point (green dot) corresponds to the BTC point