Equation Icon  { } 1- a 1-2 a 2 1-2 1-2 a 1-2 a b 3 r = s 1 + 2saa (t)ω − 8s [aa(t)ω ] − 8s ˙a0(t) − 3s ˙aa(t)ω + 6s Ra0b0(t)ω ω + 𝒪 (s ) (222 )