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Related papers: 21-cm fluctuations from primordial magnetic fields

200 papers

The light of the first astrophysical objects is expected to leave an imprint on the global 21-cm signal as it heats, excites, and ionizes neutral hydrogen. This dependence on early astrophysics introduces significant uncertainties in…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-06 Omer Zvi Katz

The reported anomalous global 21-cm signal $(T_{21})$ from the cosmic dawn era by Experiment to Detect the Global Epoch of Reionisation Signature (EDGES) could hint towards new physics beyond the standard model. The resonant conversion of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-14 Pravin Kumar Natwariya , Vivekanand Mohapatra , Hriditi Howlader

Fluctuations in the redshifted 21 centimeter emission from neutral hydrogen probe the epoch of reionization. We examine the observability of this signal and the impact of extragalactic foreground radio sources. We use cosmological…

Astrophysics · Physics 2009-11-10 Tiziana Di Matteo , Benedetta Ciardi , Francesco Miniati

In the fuzzy dark matter (FDM) model, dark matter is composed of ultra-light particles with a de Broglie wavelength of $\sim$kpc, above which it behaves like cold dark matter (CDM). Due to this, FDM suppresses the growth of structure on…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-01 Debanjan Sarkar , Jordan Flitter , Ely D. Kovetz

The redshifted 21cm signal from the Cosmic Dawn is expected to provide unprecedented insights into early Universe astrophysics and cosmology. Here we explore how dark matter can heat the intergalactic medium before the first galaxies,…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-17 Gaétan Facchinetti , Laura Lopez-Honorez , Yuxiang Qin , Andrei Mesinger

We derive constraints on primordial power spectrum, for the first time, from galaxy UV luminosity functions (LFs) at high redshifts. Since the galaxy LFs reflect an underlying halo mass function which depends on primordial fluctuations, one…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Shintaro Yoshiura , Masamune Oguri , Keitaro Takahashi , Tomo Takahashi

The density contrast of the Universe, parametrized in terms of the matter power spectrum and its variance, can amplify the signal of the free-free process in the plasma. The damping of fluctuations on scales smaller than the DM particle…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Tiziana Trombetti , Carlo Burigana

We discuss early structure formation of small scales sourced by primordial black holes (PBHs) which constitute a small part of present cold dark matter component. We calculate the mass function and power spectrum of haloes originated from…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-30 Jinn-Ouk Gong , Naoya Kitajima

A primordial magnetic field (PMF) present before recombination can leave specific signatures on the cosmic microwave background (CMB) fluctuations. Of particular importance is its contribution to the B-mode polarization power spectrum.…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 Alex Zucca , Yun Li , Levon Pogosian

A measurement of primordial non-gaussianity will be of paramount importance to distinguish between different models of inflation. Cosmic microwave background (CMB) anisotropy observations have set unprecedented bounds on the non-gaussianity…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-14 Julian B. Muñoz , Yacine Ali-Haïmoud , Marc Kamionkowski

It is shown that small-scale magnetic fields present before recombination induce baryonic density inhomogeneities of appreciable magnitude. The presence of such inhomogeneities changes the ionization history of the Universe, which in turn…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Karsten Jedamzik , Tom Abel

In this paper we study the effect of a magnetic field on the fluctuation spectrum of the cosmic microwave background. We find that upcoming measurements might give interesting bounds on large scale magnetic fields in the early Universe. If…

Astrophysics · Physics 2009-10-28 Jenni Adams , Ulf H. Danielsson , Dario Grasso , Héctor Rubinstein

We study the implications of primordial magnetic fields for the thermal and ionization history of the post-recombination era. In particular we compute the effects of dissipation of primordial magnetic fields owing to ambipolar diffusion and…

Astrophysics · Physics 2009-11-13 Shiv K Sethi , Biman B. Nath , Kandaswamy Subramanian

Primordial Magnetic Fields (PMFs) -- magnetic fields originating in the early Universe and permeating the cosmological scales today -- can explain the observed microGauss-level magnetisation of galaxies and their clusters. In light of…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-29 Salome Mtchedlidze , Franco Vazza , Xiaolong Du , Ettore Carretti , Chiara Stuardi , Shane Patrick O'Sullivan

The 21 cm signal produced by non-evaporating primordial black holes (PBHs) is investigated. X-ray photons emitted by accretion of matter onto a PBH ionize and heat the intergalactic medium (IGM) gas near the PBH. Using a simple analytic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Hiroyuki Tashiro , Naoshi Sugiyama

An unprecedented array of new observational capabilities are starting to yield key constraints on models of the epoch of first light in the Universe. In this Letter we discuss the implications of the UV radiation background at cosmic dawn…

The primordial magnetic fields (PMFs) produced in the early universe are expected to be the origin of the large-scale cosmic magnetic fields. The PMFs are considered to leave a footprint on the cosmic microwave background (CMB) anisotropies…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-17 Teppei Minoda , Kiyotomo Ichiki , Hiroyuki Tashiro

Magnetic fields appear wherever plasma and currents can be found. As such, they thread through all scales in Nature. It is natural, therefore, to suppose that magnetic fields might have been formed within the high temperature environments…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-16 Dai G. Yamazaki , Toshitaka Kajino , Grant J. Mathew , Kiyotomo Ichiki

A primordial stochastic magnetic field will induce temperature and polarization fluctuations in the cosmic microwave background. We outline a calculation of the resulting fluctuation power spectra and present numerical results.

Astrophysics · Physics 2009-10-31 Tina Kahniashvili , Arthur Kosowsky , Andrew Mack , Ruth Durrer

The formation of the first galaxies during cosmic dawn and reionization (at redshifts $z=5-30$), triggered the last major phase transition of our universe, as hydrogen evolved from cold and neutral to hot and ionized. The 21-cm line of…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-14 Julian B. Muñoz , Yuxiang Qin , Andrei Mesinger , Steven G. Murray , Bradley Greig , Charlotte Mason