The ^{144}Sm-\alpha optical potential at astrophysically relevant energies derived from ^{144}Sm(\alpha,\alpha)^{144}Sm elastic scattering

For the determination of the ${}^{144}Sm-\alpha$ optical potential we measured the angular distribution of ${}^{144}Sm(\alpha ,\alpha {)}^{144}Sm$ scattering at the energy $E_{lab}=20MeV$ with high accuracy. Using the known systematics of $\alpha$-nucleus optical potentials we are able to derive the ${}^{144}Sm-\alpha$ optical potential at the astrophysically relevant energy $E_{c\mathrm{.}m\mathrm{.}}=9.5MeV$ with very limited uncertainties.