Revisiting the oscillations in the CMB angular power spectra at $\ell\sim120$ in the Planck2015 data

TL;DR

This paper investigates the features around multipole b1120 in the Planck2015 CMB data, confirming their presence but showing they do not significantly impact cosmological parameter estimation.

Contribution

It provides a detailed analysis of the b1120 features in Planck data and assesses their influence on parameter estimation, extending previous WMAP findings.

Findings

Features at b1120 are confirmed in Planck data.

These features do not significantly alter cosmological parameters.

The analysis supports the robustness of standard cosmological models.

Abstract

While the observed nearly scale-invariant initial power spectrum is regarded as one of the favorable evidence of the standard inflationary cosmology, precision observations of the Cosmic Microwave Background (CMB) anisotropies also suggest possible existence of nontrivial features such as those observed around multipoles $\ell\sim120$ by WMAP. Here, we examine the Planck data and investigate the effects of these features on the cosmological parameter estimation performing the Markov-Chain Monte-Carlo (MCMC) analysis. We find that the features exist in the Planck data at the same position as the case of the WMAP data but they do not affect the cosmological parameter estimation significantly.