Excess of lensing amplitude in the Planck CMB power spectrum

Precise measurements of the Planck cosmic microwave background (CMB) angular power spectrum (APS) at small angles have stimulated accurate statistical analyses lensing amplitude parameter $A_{L}$. To confirm if it satisfies value expected by flat-$\Lambda$CDM concordance model, i.e. $A_{L} = 1$, we investigate difference obtained as: measured CMB APS and best-fit $\Lambda$CDM model. know this residual corresponds to noise or has a hiden signature that can be accounted for with larger > apply Ljung-Box test find, high significance, is not noise. This then analysed in detail using simulated APS, based on where free parameter. We explore different binnations multipole order \,$\ell$\, look accounts $\chi^2$ procedure. find there an excess signal well explained non-null $A_{lens}$, values interval $[0.10,0.29]$ 68\% confidence level. Furthermore, should $1 + A_{lens} 1$ $\sim 3 \sigma$ confidence. Additionally, perform tests robustness result. Important say amplitude, Planck's could impact theoretical expectation large-scale structures formation once scales was detected correspond these matter clustering processes.