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Related papers: Constraining Primordial Magnetism

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We present a measurement of the angular power spectrum of the cosmic microwave background (CMB) using data from the South Pole Telescope (SPT). The data consist of 790 square degrees of sky observed at 150 GHz during 2008 and 2009. Here we…

The fine-structure constant, $\alpha$, controls the strength of the electromagnetic interaction. There are extensions of the standard model in which $\alpha$ is dynamical on cosmological length and time-scales. The physics of the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Tristan L. Smith , Daniel Grin , David Robinson , Davy Qi

The Cosmic Microwave Background (CMB) fluctuations at very small angular scales (less than $10'$) induced by matter sources are computed in a simplified way. The result corrects a previous formula appearing in the literature. The small…

Astrophysics · Physics 2011-05-10 Mark Hindmarsh

A possible explanation for the origin of the magnetic fields observed today in matter structures is that they were generated in the primordial universe. After briefly revising the model of a primordial stochastic magnetic field and…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Chiara Caprini

In recent years the goal of estimating different cosmological parameters precisely has set new challenges in the effort to accurately measure the angular power spectrum of CMB. This has required removal of foreground contamination as well…

Astrophysics · Physics 2008-11-26 Rajib Saha , Simon Prunet , Pankaj Jain , Tarun Souradeep

The cosmic microwave background (CMB) bispectrum is a well-known probe of the non-Gaussianity of primordial perturbations. Just as the intervening large-scale structure modifies the CMB angular power spectrum through weak gravitational…

Astrophysics · Physics 2008-11-26 Asantha Cooray , Devdeep Sarkar , Paolo Serra

Primordial Magnetic Fields (PMFs), long studied as relics of the early Universe, accelerate recombination and have been proposed as a way to relieve the Hubble tension. However, previous studies relied on simplified toy models. Here we use…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-17 Karsten Jedamzik , Levon Pogosian , Tom Abel

The observed galactic magnetic fields may have a primordial origin. I briefly review the observations, their interpretation in terms of the dynamo theory, and the current limits on cosmological magnetic fields. Several possible mechanisms…

Astrophysics · Physics 2007-05-23 Kari Enqvist

Cosmic strings are a type of cosmic defect formed by a symmetry-breaking phase transition in the early universe. Individual strings would have gathered to build a network, and their dynamical motion would induce scalar--, vector-- and…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-07 Kouichirou Horiguchi , Kiyotomo Ichiki , Naoshi Sugiyama

The precision of Cosmic Microwave Background (CMB) experiments, specifically its lensing reconstruction, has reached the limit where non-linear corrections cannot be ignored. Neglecting these corrections results in biased constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-27 Cynthia Trendafilova , Ali Rida Khalife , Silvia Galli

The origin of large magnetic fields in the Universe remains currently unknown. We investigate here a mechanism before recombination based on known physics. The source of the vorticity is due to the changes in the photon distribution…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 Ophélia Fabre , S. Shankaranarayanan

We investigate early dark energy models in the context of the lensing anomaly by considering two different Cosmic Microwave Background (CMB) datasets: a complete Planck, and a second one primarily based on SPTPol and Planck temperature…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-20 Balakrishna S. Haridasu , Hasti Khoraminezhad , Matteo Viel

Magnetic fields are observed not only in stars, but in galaxies, clusters, and even high redshift Lyman-alpha systems. In principle, these fields could play an important role in structure formation and also affect the anisotropies in the…

Astrophysics · Physics 2009-10-31 Roy Maartens

We set limits on the presence of the synchrotron cosmic web through the cross-correlation of the 2.3 GHz S-PASS survey with a model of the local cosmic web derived from constrained magnetohydrodynamic (MHD) simulations. The MHD simulation…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-10 S. Brown , T. Vernstrom , E. Carretti , K. Dolag , B. M. Gaensler , L. Staveley-Smith , G. Bernardi , M. Haverkorn , M. Kesteven , S. Poppi

Primordial non-Gaussianities (PNGs) are imprints in the initial density field sourced by the dynamics of inflation. These dynamics can induce scale dependence, oscillations, and other features in the primordial bispectrum. We analyze a…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-24 Dhayaa Anbajagane , Hayden Lee

We report cosmic microwave background (CMB) power spectrum measurements from the first 100 sq. deg. field observed by the South Pole Telescope (SPT) at 150 and 220 GHz. On angular scales where the primary CMB anisotropy is dominant, ell ~<…

The origin of the substantial magnetic fields that are found in galaxies and on even larger scales, such as in clusters of galaxies, is yet unclear. If the second-order couplings between photons and electrons are considered, then…

We perform a multiparameter likelihood analysis to compare measurements of the cosmic microwave background (CMB) power spectra with predictions from models involving cosmic strings. Adding strings to the standard case of a primordial…

Astrophysics · Physics 2008-11-26 Neil Bevis , Mark Hindmarsh , Martin Kunz , Jon Urrestilla

Primordial magnetic fields (PMFs) enhance small-scale structure formation through the Lorentz force acting on baryons, boosting the abundance of low-mass halos and their hosted galaxies. We show that the reionisation history calibrated with…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-29 Malcolm Fairbairn , María Olalla Olea-Romacho , Juan Urrutia , Ville Vaskonen

Bounds on the amplitude of a scale-invariant stochastic primordial magnetic field (PMF) can be significantly improved by measurements of the Faraday Rotation (FR) of CMB polarization. The mode-coupling correlations induced by FR make it…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-26 Levon Pogosian
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