0 1 2 3 4 b/b$_{0}$ 0.5 0.6 0.7 2 a nd  [fm] 0 1 2 3 4 b/b$_{0}$ 28.2 28.3 28.4 B( 4  He) [MeV] c$_{E}$=0 c$_{E}$=0.6 c$_{E}$=1.0 c$_{E}$=1.4 c$_{E}$=1.0 c$_{E}$=1.4 c$_{E}$=0.6 =4.0 m 0 0.5 1 1.5 2 2.5 3 b/b$_{0}$ 0.5 0.6 0.7 2 a nd  [fm] 0 0.5 1 1.5 2 2.5 3 b/b$_{0}$ 28.2 28.3 28.4 28.5 B( 4 He) [MeV] c$_{E}$=0 c$_{E}$=1.0 c$_{E}$=1.6 c$_{E}$=2.2 c$_{E}$=2.2 c$_{E}$=1.6 =4.8 m 0 0.5 1 1.5 2 b/b$_{0}$ 0.5 0.55 0.6 0.65 0.7 2 a nd  [fm] 0 0.5 1 1.5 2 b/b$_{0}$ 28.2 28.3 28.4 28.5 28.6 B( 4 He) [MeV] c$_{E}$=0 c$_{E}$=1 c$_{E}$=2 c$_{E}$=2.2 c$_{E}$=2.4 c$_{E}$=2.6 c$_{E}$=2 c$_{E}$=2.2 c$_{E}$=2.4 c$_{E}$=2.6 =5.6 m FI G . 3: The doublet scattering length a$_{nd}$ as a function of the parameter b (in units of b$_{0}$ = − 2 . 5 8 m − 3 π ) of the TM’ potential including the W TM E -term, for different values of the strength c$_{E}$ and for three selected values of Λ. The corresponding values of B ( $^{4}$He), for specific values of a$_{nd}$ insi de the box, are shown in the right panels (circles). 24