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相关论文: Revisiting primordial magnetic fields through 21-c…

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A primordial magnetic field with the strength in the 1-10 pG range can resolve the tension between different measurements of the Hubble constant and provide an explanation for the excess opacity in the 21 cm line at redshift $15<z<20$, if…

宇宙学与河外天体物理 · 物理学 2021-06-22 A. Korochkin , O. Kalashev , A. Neronov , D. Semikoz

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…

宇宙学与河外天体物理 · 物理学 2021-05-17 Teppei Minoda , Kiyotomo Ichiki , Hiroyuki Tashiro

Big bang nucleosynthesis (BBN) is affected by the energy density of a primordial magnetic field (PMF). For an easy derivation of constraints on models for PMF generations, we assume a PMF with a power law (PL) distribution in wave number…

宇宙学与河外天体物理 · 物理学 2012-12-14 Dai G. Yamazaki , Motohiko Kusakabe

Damping of magnetic fields via ambipolar diffusion and decay of magnetohydrodynamical (MHD) turbulence in the post decoupling era heats the intergalactic medium (IGM). Delayed recombination of hydrogen atoms in the IGM yields an optical…

宇宙学与河外天体物理 · 物理学 2015-05-26 Kerstin E. Kunze , Eiichiro Komatsu

Magnetic fields are an important ingredient of the interstellar medium (ISM). Besides their importance for star formation, they govern the transport of cosmic rays, relevant to the launch and regulation of galactic outflows and winds, which…

The explanation of the observed galactic magnetic fields may require the existence of a primordial magnetic field. Such a field may arise during the early cosmological phase transitions, or because of other particle physics related…

天体物理学 · 物理学 2009-10-30 Kari Enqvist

We propose a method of measuring extremely weak magnetic fields in the intergalactic medium prior to and during the epoch of cosmic reionization. The method utilizes the Larmor precession of spin-polarized neutral hydrogen in the triplet…

宇宙学与河外天体物理 · 物理学 2017-12-20 Tejaswi Venumadhav , Antonija Oklopcic , Vera Gluscevic , Abhilash Mishra , Christopher M. Hirata

(abridged) A detailed examination of the evolution of stochastic magnetic fields between high cosmic temperatures and the present epoch is presented. A simple analytical model matching the results of the 3D MHD simulations allows for the…

天体物理学 · 物理学 2009-11-10 Robi Banerjee , Karsten Jedamzik

Recent FERMI observations provide a lower limit of 10^{-15} G for the magnetic field strength in the intergalactic medium (IGM). This is consistent with theoretical expectations based on the Biermann battery effect, which predicts such IGM…

The cosmic 21-cm signal is a promising probe of the early Universe, owing to its sensitivity to the thermal state of the neutral intergalactic medium (IGM) and properties of the first luminous sources. Here, we constrain the 21-cm signal…

The aim of this thesis is to study the effects on the CMB anisotropy due to primordial magnetic fields and to analyze some favorable scenarios of magnetogenesis constrained by those signatures, including limits on the amplitude of the…

宇宙学与河外天体物理 · 物理学 2019-03-12 Hector J. Hortua

Primordial magnetic fields (PMFs) generated in the early Universe may leave observable imprints in the present-day large-scale structure. However, it remains unclear on which spatial scales primordial signatures can survive the nonlinear…

宇宙学与河外天体物理 · 物理学 2026-02-27 Jennifer Schober , Molly Abramson , Sayan Mandal , Salome Mtchedlidze , Tina Kahniashvili

The measurement of the large scale distribution of neutral hydrogen in the late Universe, obtained with radio telescopes through the hydrogen 21cm line emission, has the potential to become a key cosmological probe in the upcoming years. We…

宇宙学与河外天体物理 · 物理学 2023-03-15 Maria Berti , Marta Spinelli , Matteo Viel

Magnetic fields play an important role in shaping the structure and evolution of the interstellar medium (ISM) of galaxies, but the details of this relationship remain unclear. With SKA1, the 3D structure of galactic magnetic fields and its…

We study the impact of the extra density fluctuations induced by primordial magnetic fields on the reionization history in the redshift range: $6 < z < 10$. We perform a comprehensive MCMC physical analysis allowing the variation of…

宇宙学与河外天体物理 · 物理学 2015-05-13 Kanhaiya L. Pandey , T. Roy Choudhury , Shiv K. Sethi , Andrea Ferrara

Magnetic fields in pre main sequence stars regulate angular momentum evolution, drive magnetic activity, and modify stellar structure, yet their surface distributions remain poorly constrained. Traditional single component Zeeman broadening…

太阳与恒星天体物理 · 物理学 2025-09-26 Facundo Pérez Paolino , Lynne Hillenbrand , Jeff Bary

Galactic magnetic fields are observed of order $\sim 10^{-6}G$, but their origin is not definitely known yet. In this paper we consider the primordial magnetic fields generated in the early universe and analyse their effects on the density…

天体物理学 · 物理学 2016-08-30 Seoktae Koh , Chul H. Lee

Spatially varying primordial magnetic fields may be efficiently dissipated prior to the epoch of recombination due to the large viscosity of the baryon-photon fluid. We show that this dissipation may result in observable chemical potential…

天体物理学 · 物理学 2009-10-31 K. Jedamzik , V. Katalinic , A. V. Olinto

Magnetic field strengths in objects ranging from HII regions to cosmological large scale structure can be estimated using dense grids of Rotation Measures (RMs) from polarized background radio structures. Upcoming surveys on the SKA and its…

星系天体物理 · 物理学 2019-01-29 Lawrence Rudnick

Observational limits on $y$- and $\mu$-type distortions can constrain properties of magnetic fields in the early universe. For a Gaussian, random, and non-helical field, $\mu$ and $y$ are calculated a function of the present-day strength of…

宇宙学与河外天体物理 · 物理学 2014-01-30 Kerstin E. Kunze , Eiichiro Komatsu