Power spectrum of post-inflationary primordial magnetic fields

Héctor J. Hortúa; Leonardo Castañeda

doi:10.1103/physrevd.90.123520

Thermal Sunyaev–Zel’dovich Effect in the IGM due to Primordial Magnetic Fields

Galaxies ◽

10.3390/galaxies6040143 ◽

2018 ◽

Vol 6 (4) ◽

pp. 143 ◽

Cited By ~ 3

Author(s):

Teppei Minoda ◽

Kenji Hasegawa ◽

Hiroyuki Tashiro ◽

Kiyotomo Ichiki ◽

Naoshi Sugiyama

Keyword(s):

Magnetic Fields ◽

Power Spectrum ◽

Mass Density ◽

Temperature Anisotropy ◽

Angular Power Spectrum ◽

Stringent Constraint ◽

Small Scales ◽

Sunyaev Zel'dovich Effect ◽

Primordial Magnetic Fields ◽

Initial Power

In the present universe, magnetic fields exist with various strengths and on various scales. One possible origin of these cosmic magnetic fields is the primordial magnetic fields (PMFs) generated in the early universe. PMFs are considered to contribute to matter density evolution via Lorentz force and the thermal history of intergalactic medium (IGM) gas due to ambipolar diffusion. Therefore, information about PMFs should be included in the temperature anisotropy of the Cosmic Microwave Background through the thermal Sunyaev–Zel’dovich (tSZ) effect in IGM. In this article, given an initial power spectrum of PMFs, we show the spatial fluctuation of mass density and temperature of the IGM and tSZ angular power spectrum created by the PMFs. Finally, we find that the tSZ angular power spectrum induced by PMFs becomes significant on small scales, even with PMFs below the observational upper limit. Therefore, we conclude that the measurement of tSZ anisotropy on small scales will provide the most stringent constraint on PMFs.

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Sunyaev-Zel'dovich power spectrum produced by primordial magnetic fields

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2010.17767.x ◽

2010 ◽

Vol 411 (2) ◽

pp. 1284-1292 ◽

Cited By ~ 9

Author(s):

Hiroyuki Tashiro ◽

Naoshi Sugiyama

Keyword(s):

Magnetic Fields ◽

Power Spectrum ◽

Primordial Magnetic Fields

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Constraining the primordial magnetic field with dwarf galaxy simulations

Astronomy and Astrophysics ◽

10.1051/0004-6361/202038382 ◽

2020 ◽

Vol 643 ◽

pp. A54 ◽

Cited By ~ 1

Author(s):

Mahsa Sanati ◽

Yves Revaz ◽

Jennifer Schober ◽

Kerstin E. Kunze ◽

Pascale Jablonka

Keyword(s):

Dark Matter ◽

Magnetic Fields ◽

Power Spectrum ◽

Dwarf Galaxies ◽

Magnetic Energy ◽

Dwarf Galaxy ◽

High Amplitude ◽

Density Fluctuations ◽

Large Set ◽

Primordial Magnetic Fields

Using a set of cosmological hydro-dynamical simulations, we constrained the properties of primordial magnetic fields by studying their impact on the formation and evolution of dwarf galaxies. We performed a large set of simulations (8 dark matter only and 72 chemo-hydrodynamical) including primordial magnetic fields through the extra density fluctuations they induce at small length scales (k ≥ 10 h Mpc−1) in the matter power spectrum. Our sample of dwarfs includes nine systems selected out of the initial (3.4 Mpc h−1)3 parent box, resimulated from z = 200 to z = 0 using a zoom-in technique and including the physics of baryons. We explored a wide variety of primordial magnetic fields with strength Bλ ranging from 0.05 to 0.50 nG and magnetic energy spectrum slopes nB from −2.9 to −2.1. Strong magnetic fields characterized by a high amplitude (Bλ = 0.50, 0.20 nG with nB = −2.9) or by a steep initial power spectrum slope (nB = −2.1, −2.4, with Bλ = 0.05 nG) induce perturbations on mass scales from 107 to 109 M⊙. In this context emerging galaxies see their star formation rates strongly boosted. They become more luminous and metal rich than their counterparts without primordial magnetic fields. Such strong fields are ruled out by their inability to reproduce the observed scaling relations of dwarf galaxies. They predict that dwarf galaxies are at the origin of an unrealistically early reionization of the Universe and that they also overproduce luminous satellites in the Local Group. Weaker magnetic fields impacting the primordial density field at corresponding masses ≲106 M⊙, produce a large number of mini dark matter halos orbiting the dwarfs, however out of reach for current lensing observations. This study allows us, for the first time, to constrain the properties of primordial magnetic fields based on realistic cosmological simulations of dwarf galaxies.

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