Searching for primordial localized features with CMB and LSS spectra

Abstract

Inspired by the study of mild transient reductions in the speed of sound of the adiabatic mode during inflation, we search for a primordial localized feature imprinted in cosmic microwave background and large-scale structure formation observables. We find some common oscillatory patterns both in the Planck CMB temperature-temperature power spectrum and the WiggleZ galaxy spectrum. By performing independent searches with these two data sets, we find a coincidence in the most significant mode previously found by Achúcarro et al. 2013 by using only Planck data. Furthermore, the joint data analysis shows that the oscillation frequency of the feature gets better constrained, and the amplitude marginally deviates from zero, unlike what was observed using only Planck data. Besides the parameter estimation, we also discuss the Bayesian evidence. The addition of WiggleZ data mildly enhances the significance of the best mode found in the Planck data.

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References in corpus (13)

• Generation and Characterization of Large Non-Gaussianities in Single Field Inflation
• Inflation and WMAP three year data: Features have a Future!
• Mass hierarchies and non-decoupling in multi-scalar field dynamics
• Efficient Bayesian inference for multimodal problems in cosmology
• New Constraints on Oscillations in the Primordial Spectrum of Inflationary Perturbations
• Standard Clock in Primordial Density Perturbations and Cosmic Microwave Background
• Inflation with moderately sharp features in the speed of sound: GSR and in-in formalism for power spectrum and bispectrum
• Generalized Slow Roll for Non-Canonical Kinetic Terms
• Searching for Standard Clocks in the Primordial Universe
• The effect of varying sound velocity on primordial curvature perturbations
• Strong scale dependent bispectrum in the Starobinsky model of inflation
• Perturbative Unitarity of Inflationary Models with Features
• The Komatsu Spergel Wandelt estimator for oscillations in the cosmic microwave background bispectrum

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• Scratches from the Past: Inflationary Archaeology through Features in the Power Spectrum of Primordial Fluctuations
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• Planck residuals anomaly as a fingerprint of alternative scenarios to inflation
• Searching for features of a string-inspired inflationary model with cosmological observations
• Consistency relations for sharp features in the primordial spectra
• Euclid: The search for primordial features
• Impacts of dark energy on constraining neutrino mass after Planck 2018
• Bayesian analysis of inflationary features in Planck and SDSS data
• Bayesian reconstruction of the inflaton's speed of sound using CMB data
• Late time sky as a probe of steps and oscillations in primordial Universe
• Robust predictions for an oscillatory bispectrum in Planck 2015 data from transient reductions in the speed of sound of the inflaton
• High-resolution CMB bispectrum estimator with flexible modal basis
• Primordial feature constraints from BOSS+eBOSS
• CMB-S4 forecast on the primordial non-Gaussianity parameter of feature models
• Probing primordial features with the primary CMB
• Consistency relations for sharp inflationary non-Gaussian features
• Knot reconstruction of the scalar primordial power spectrum with Planck, ACT, and SPT CMB data
• Refining the nonlinear modelling of primordial oscillatory features
• Scalar-induced gravitational waves in spatially covariant gravity