Spin-orbit coupling for close-in planets

The paper derives the standard capture-probability formula Pcap = 1 − T−/T+ under the weak-torque, adiabatic-separatrix-crossing assumption and uniform entrance phase, then evaluates T± for a Maxwell rheology in closed form (its Eqs. (66)–(67))—precisely matching the model’s result and assumptions. The steps in the paper (energy-balance ∆h over a loop, weak-torque approximation γ̇ ≈ ±βr cos γ, and the Maxwell-torque integral) align with the model’s flux/energy derivation and its complex-log integral, yielding identical expressions for T±, including Δ±k and δ±k. See the derivation of Pcap (Eq. (66)) and the explicit Maxwell closed form (Eq. (67)) in the paper , together with the averaged near-resonant equation (Eq. (59)) and torque definition (Eq. (55)) .