Degree-scale anomalies in the CMB: Localizing the first peak dip to a small patch of the north ecliptic sky

Noticeable deviations from the prediction of the fiducial lambda cold dark matter cosmology are found in the angular power spectrum of the cosmic microwave background. Besides large-angle anomalies, the WMAP first year data revealed a dip in the power spectrum at l∼200, which seemed to disappear in the third year and subsequent angular power spectra. Using the WMAP single first, third, and fifth year data as well as the total 5 yr coadded data, we study the intensity and spatial distribution of this feature in order to unveil its origin and its implications for the cosmological parameters. We show that in the 5 yr coadded WMAP data release there is a suppression of the first Doppler peak in a region near the north ecliptic pole at a significance level between 99% and 96% depending on the weighting scheme that is considered.