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frequencies given by Eqs. (4) are shifted from those corresponding to bare molecular states by the amount δω ( B$_{rf}$ ) ∼ B 2 rf [28]. Because the rf-induced coupling is weak and α$_{bg}$ is large, the real part of the scattering length does not vary appreciably in the vicinity of the resonances, increasing from 103.7 to 106.5 a$_{0}$ near the resonance D as the rf frequency is scanned from 31.405 to 31.413 MHz. The inelastic loss rate at the resonance is ∼ 10 − 12 cm $^{3}$/s. From Eqs. (4), it is clear that α can be controlled more efficiently in atomic systems with smaller α$_{bg}$ . Alternatively, α$_{bg}$ can be reduced using magnetic [1] or electric [7] Feshbach resonances. 

As follows from Eqs. (4), α and β peak at different rf detunings: Δ$_{α}$ = ± γ$_{ba}$/ 2 and Δ$_{β}$ = 0, with peak heights ∼ γ$_{ib}$/γ$_{ba}$ . Therefore, to induce an appreciable variation of α 

