Direct space-charge force shifts the incoherent tunes down from the coherent ones switching off Landau damping of coherent oscillations at high beam intensity. To restore it the nonlinear elements can be employed which move back tunes of large amplitude particles. In the present report we consider the possibility of creating a "nonlinear integrable optics" insertion in the Fermilab Recycler to host either octupoles or hollow electron lens for this purpose. For comparison we also consider the

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... lso consider the classic scheme with distributed octupole families. It is shown that for the Proton Improvement Plan II parameters the required nonlinear tuneshift can be created without destroying the dynamic aperture.