A new search for features in the primordial power spectrum.

We develop a new approach towards a high-resolution non-parametric reconstruction of the primordial power spectrum using theWilkinson Microwave Anisotropy Probe(WMAP) cosmic microwave background temperature anisotropies that we confront with Sloan Digital Sky Survey large-scale structure data in the range. We utilize the standardΛ cold dark matter cosmological model but we allow the baryon fraction to vary. In particular, for the concordance baryon fraction, we compare indications of a possible feature atinWMAPdata with suggestions of similar features in large-scale structure surveys. [ABSTRACT FROM AUTHOR]