On effective determination of modular forms by twists of critical L-values

We address the problem of identifying a newform f from the central values of the twisted L-functions ${L(1/2,fotimes chi)}We address the problem of identifying a newform f from the central values of the twisted L-functions L(1/2,f?c){L(1/2,fotimes chi)} where χ runs through the set of real characters. We prove a quantitative result in this direction.