Determination of asymptotic normalization coefficients for the channel $$^{16}$$O$$\rightarrow \alpha +^{12}$$C: excited state $$^{16}$$O($$0^+; 6.05$$ MeV)

Asymptotic normalization coefficients (ANC) determine the overall of cross sections peripheral radiative capture reactions. In present paper, we treat ANC $C$ for virtual decay $^{16}$O$(0^+; 6.05$ MeV)$\to \alpha+^{12}$C(g.s.), known values which are characterized by a large spread $(0.29-1.65)\times 10^3$ fm$^{-1/2}$. The is found analytic continuation in energy $\alpha^{12}$C $s$-wave scattering amplitude, from phase-shift analysis experimental data, to pole corresponding $^{16}$O bound state and lying unphysical region negative energies. To $C$, two different methods used. first method, data approximated sum polynomials physical then extrapolated pole. best way extrapolation chosen on basis exactly solvable model. Within second approach, solving Schr\"odinger equation two-body potential, parameters selected requirement description at fixed binding MeV) $\alpha+^{12}$C channel. obtained within these lie interval (886--1139)