We consider the Schrödinger operator Hγ = ( − Δ)l + γ V(x)· acting in the space
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\begin{document}$$L_2 (\mathbb{R}^d ),$$\end{document} where 2l ≥ d, V (x) ≥ 0, V (x) is continuous and is not identically zero, and
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\begin{document}$$\lim _{|{\mathbf{x}}| \to \infty } V({\mathbf{x}}) = 0.$$\end{document} We study the asymptotic behavior as
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\begin{document}$$\gamma\,\uparrow\,0$$\end{document} of the non-bottom negative eigenvalues of Hγ, which are born at the moment γ = 0 from the lower bound λ = 0 of the spectrum σ(H0) of the unperturbed operator H0 = ( − Δ)l (virtual eigenvalues). To this end we use the Puiseux-Newton diagram for a power expansion of eigenvalues of some class of polynomial matrix functions. For the groups of virtual eigenvalues, having the same rate of decay, we obtain asymptotic estimates of Lieb-Thirring type.