\displaystyle \Big( \int_{0}^{\infty}  \int_{|\xi|\sim s^{-1} \lambda} |\widehat{f}(\xi)|^2 s^2 \lambda^{-2} (s|\xi|)^{-(d-1)}|\xi|^2 \,\frac{ds}{s} \,d\xi \Big)^{1/2}, 