text: FIG. 23: Kinetic energy diﬀerence between the SCS and the 
  NS, δKE We set λ to be either λ = 1 or λ = 10 and varied ωsf 
  thus changing the overall prefactor in the self-energy. At weak 
  coupling (λ = 1) the behavior is BCS-like – δKE is positive 
  and increases with the overall factor in the self-energy. At 
  strong coupling (λ = 7), δKE shows a reverse trend at larger 
  ωsf . 