Estimate $L^2$ norm of Fourier transform

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I am trying to compute the following quantity:

$$ \sum_{k=-\infty}^{\infty} 2^{k \frac{1}{2}}\left\{\int_{\Gamma_k}|\widehat{f}(x)|^2 d x\right\}^{\frac{1}{2}}$$

where: $ \Gamma_k=\left\{x \in \mathbb{R}: 2^{k-1}<\left|x\right|<2^k\right\}$ and:

$$ f(x) = \delta^{-1} x^{1/4} 1_{(\delta,M)}(x)$$

where $\delta$ and $M$ are costants. Any idea on how to tackle this problem?