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

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We investigate bounds on the strength of the primordial magnetic field (PMF) from the cosmic microwave background (CMB) bispectra of the intensity (temperature) modes induced from the auto- and cross-correlated bispectra of the scalar and…

宇宙学与河外天体物理 · 物理学 2012-04-02 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki

We study the effect of primordial magnetic fields (PMFs) on the anisotropies of the cosmic microwave background (CMB). We assume the spectrum of PMFs is described by log-normal distribution which has a characteristic scale, rather than…

宇宙学与河外天体物理 · 物理学 2011-12-30 Dai G. Yamazaki , Kiyotomo Ichiki , Keitaro Takahashi

We analyse the impact of the decaying magnetic turbulence of primordial magnetic fields (PMFs) and ambipolar diffusion on the ionisation and thermal history of the Dark Ages Universe ($30\le z\le300$), and its imprint on the spectral…

宇宙学与河外天体物理 · 物理学 2026-02-04 Bohdan Novosyadlyj , Yurii Kulinich , Nazar Fortuna , Anton Rudakovskyi

We investigate the impact of the recent observation of the 21cm global signal by EDGES on primordial power spectrum, particularly focusing on the running parameters $\alpha_s$ and $ \beta_s$ which characterize the detailed scale dependence…

宇宙学与河外天体物理 · 物理学 2018-10-03 Shintaro Yoshiura , Keitaro Takahashi , Tomo Takahashi

Primordial magnetic fields (PMFs) may explain observations of magnetic fields on extragalactic scales. They are most cleanly constrained by measurements of cosmic microwave background radiation (CMB) anisotropies. Their effects on cosmic…

宇宙学与河外天体物理 · 物理学 2024-11-18 Karsten Jedamzik , Tom Abel , Yacine Ali-Haimoud

Magnetic fields appear to be present in essentially all astrophysical environments, including galaxies, clusters of galaxies and voids. There are both observational and theoretical motives for considering the possibility of their origin…

宇宙学与河外天体物理 · 物理学 2023-07-12 Karsten Jedamzik , Levon Pogosian

The universe is magnetized on all scales probed so far. On the largest scales, galaxies and galaxy clusters host magnetic fields at the micro Gauss level coherent on scales up to ten kpc. Recent observational evidence suggests that even the…

宇宙学与河外天体物理 · 物理学 2017-05-26 Kandaswamy Subramanian

We constrain a stochastic background of primordial magnetic fields (PMF) by its contribution to the cosmic microwave background (CMB) anisotropy angular power spectrum with the combination of WMAP 7 year and South Pole Telescope (SPT) data.…

宇宙学与河外天体物理 · 物理学 2013-10-23 Daniela Paoletti , Fabio Finelli

The Faraday rotation effect, quantified by the Rotation Measure (RM), is a powerful probe of the large-scale magnetization of the Universe - tracing magnetic fields not only on galaxy and galaxy cluster scales but also in the intergalactic…

The magnetic deformation of magnetars is affected by their internal magnetic fields, which are generally difficult to be measured directly through observations. In this work, the periodic pulse-phase modulations in the hard X-ray emissions…

高能天体物理现象 · 物理学 2025-01-07 Jie Shu , Quan Cheng , Xiao-Ping Zheng

Weak magnetic fields must have existed in the early Universe, as they were sourced by the cross product of electron density and temperature gradients through the Biermann-battery mechanism. In this paper we calculate the magnetic fields…

宇宙学与河外天体物理 · 物理学 2024-08-15 Nanoom Lee , Yacine Ali-Haimoud

In this paper, we revisit in detail the effects of primordial magnetic fields on big bang nucleosynthesis (BBN) including a discussion of the magnetic field geometry and the anomalous magnetic moment. The presence of magnetic fields affects…

天体物理学 · 物理学 2009-12-30 Baolian Cheng , Angela V. Olinto , David N. Schramm , James W. Truran

We reconstruct the 3D structure of magnetic fields, which were seeded by density perturbations during the radiation dominated epoch of the Universe and later on were evolved by structure formation. To achieve this goal, we rely on three…

宇宙学与河外天体物理 · 物理学 2019-10-21 Sebastian Hutschenreuter , Sebastian Dorn , Jens Jasche , Franco Vazza , Daniela Paoletti , Guilhem Lavaux , Torsten A. Enßlin

The origin of astrophysical magnetic fields observed in galaxies and clusters of galaxies is still unclear. One possibility is that primordial magnetic fields generated in the early Universe provide seeds that grow through compression and…

宇宙学与河外天体物理 · 物理学 2015-06-11 C. Fedeli , L. Moscardini

The cosmological 21-cm signal from neutral hydrogen, which is considered as a promising tool, is being used to observe and study the cosmic dawn (CD) and epoch of reionization (EoR). A significant part of this thesis focuses on the…

宇宙学与河外天体物理 · 物理学 2023-11-23 Ankita Bera

We study the 21-cm differential brightness temperature in the presence of primordial helical magnetic fields for redshift $z=10-30$. We argue that the $\alpha$-effect that sets in at earlier time can be helpful in lowering the gas…

宇宙学与河外天体物理 · 物理学 2020-06-25 Pravin Kumar Natwariya , Jitesh R. Bhatt

The presence of magnetic fields in the early universe affects the cosmological processes, leading to the distinct signature, which allows constraining their properties and the genesis mechanisms. In this study, we revisit the method to…

宇宙学与河外天体物理 · 物理学 2024-11-13 Ashu Kushwaha , Teruaki Suyama

Context. The existence of magnetic fields in the circumgalactic medium (CGM) is largely unconstrained. Their detection is important as magnetic fields can have a significant impact on the evolution of the CGM and, in turn, the fields can…

We examine the potential of polarization bispectra of the cosmic microwave background (CMB) to constrain primordial magnetic fields (PMFs). We compute all possible bispectra between temperature and polarization anisotropies sourced by PMFs…

宇宙学与河外天体物理 · 物理学 2013-11-07 Maresuke Shiraishi

Primordial magnetic fields (PMFs) are magnetic fields generated during the early universe. These fields are thought to be the seeds of extragalactic magnetic fields. The origin of PMFs is not well known. Further, if they are indeed sources…

广义相对论与量子宇宙学 · 物理学 2026-01-30 Ganga R. Nair , V. Sreenath