中文
相关论文

相关论文: The cosmic microwave background temperature bispec…

200 篇论文

Primordial magnetic fields lead to non-Gaussian signals in the Cosmic Microwave Background (CMB) even at the lowest order, as magnetic stresses, and the temperature anisotropy they induce, depend quadratically on the magnetic field. In…

宇宙学与河外天体物理 · 物理学 2009-09-03 T. R. Seshadri , Kandaswamy Subramanian

Primordial magnetic fields will generate non-Gaussian signals in the cosmic microwave background (CMB) as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. We compute a new measure of…

宇宙学与河外天体物理 · 物理学 2012-06-15 Pranjal Trivedi , T. R. Seshadri , Kandaswamy Subramanian

Primordial magnetic fields lead to non-Gaussian signals in the cosmic microwave background (CMB) even at the lowest order, as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. In…

宇宙学与河外天体物理 · 物理学 2011-01-17 Pranjal Trivedi , Kandaswamy Subramanian , T. R. Seshadri

Cosmic magnetic fields are observed to be coherent on large scales and could have a primordial origin. Non-Gaussian signals in the cosmic microwave background (CMB) are generated by primordial magnetic fields as the magnetic stresses and…

宇宙学与河外天体物理 · 物理学 2014-03-05 Pranjal Trivedi , Kandaswamy Subramanian , T. R. Seshadri

If the seed magnetic fields exist in the early Universe, tensor components of their anisotropic stresses are not compensated prior to neutrino decoupling and the tensor metric perturbations generated from them survive passively.…

宇宙学与河外天体物理 · 物理学 2011-06-10 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki , Keitaro Takahashi

In this work we investigate the effects of the primordial magnetic fields on cosmic microwave background anisotropies (CMB). Based on cosmological magnetohydrodynamic (MHD) simulations we calculate the CMB anisotropy spectra and…

天体物理学 · 物理学 2009-11-13 Hiroyuki Tashiro , Naoshi Sugiyama , Robi Banerjee

Primordial magnetic fields (PMFs) create a large squeezed-type non-Gaussianity in tensor perturbation, which generates non-Gaussian temperature fluctuations in the cosmic microwave background (CMB). We for the first time derive an…

宇宙学与河外天体物理 · 物理学 2014-11-13 Maresuke Shiraishi , Toyokazu Sekiguchi

Cosmic Microwave Background (CMB) Anisotropies is a subject of intensive research in several fields of sciences. In this paper we start a systematic development of basic notions and theory in statistics according to the application for CMB.…

应用统计 · 统计学 2013-12-30 Gyorgy Terdik

The cosmological magnetic field is one of the important physical quantities which affect strongly the cosmic microwave background (CMB) power spectrum. Recent CMB observations have been extended to higher multipoles $l\gtrsim$1000, and they…

天体物理学 · 物理学 2009-11-10 D. G. Yamazaki , K. Ichiki , T. Kajino

We study statistical anisotropies generated in the observed two-point function of the cosmic microwave background (CMB) fluctuations if the primordial statistics are non-Gaussian. Focusing on the dipole modulations of the anisotropies, we…

宇宙学与河外天体物理 · 物理学 2018-07-17 Saroj Adhikari , Anne-Sylvie Deutsch , Sarah Shandera

An inhomogeneous cosmological magnetic field creates vortical perturbations that survive Silk damping on much smaller scales than compressional modes. This ensures that there is no sharp cut-off in anisotropy on arc-minute scales. As we had…

天体物理学 · 物理学 2009-11-07 Kandaswamy Subramanian , John D. Barrow

Spatially fluctuating primordial magnetic fields (PMFs) inhomogeneously reheat the Universe when they dissipate deep inside the horizon before recombination. Such an energy injection turns into an additional photon temperature perturbation.…

宇宙学与河外天体物理 · 物理学 2019-11-28 Shohei Saga , Atsuhisa Ota , Hiroyuki Tashiro , Shuichiro Yokoyama

Recent observations of the cosmic microwave background (CMB) have extended the measured power spectrum to higher multipoles $l\gtrsim$1000, and there appears to be possible evidence for excess power on small angular scales. The primordial…

天体物理学 · 物理学 2009-02-19 D. Yamazaki , K. Ichiki , T. Kajino , G. J. Mathews

Possible signatures of primordial magnetic fields on the Cosmic Microwave Background (CMB) temperature and polarization anisotropies are reviewed. The signals that could be searched for include excess temperature anisotropies particularly…

天体物理学 · 物理学 2009-11-11 Kandaswamy Subramanian

A stochastic magnetic field in the early Universe will produce anisotropies in the temperature and polarization of the cosmic microwave background. We derive analytic expressions for the microwave background temperature and polarization…

天体物理学 · 物理学 2008-11-26 Andrew Mack , Tina Kahniashvili , Arthur Kosowsky

We develop the formalism necessary to study four-point functions of the cosmic microwave background (CMB) temperature and polarization fields. We determine the general form of CMB trispectra, with the constraints imposed by the assumption…

天体物理学 · 物理学 2011-05-12 Takemi Okamoto , Wayne Hu

We study the contribution of a stochastic background (SB) of primordial magnetic fields (PMF) on the anisotropies in temperature and polarization of the cosmic microwave background radiation (CMB). A SB of PMF modelled as a fully…

天体物理学 · 物理学 2011-02-11 Daniela Paoletti , Fabio Finelli , Francesco Paci

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

This article investigates the non-linear evolution of cosmological perturbations on sub-Hubble scales in order to evaluate the unavoidable deviations from Gaussianity that arise from the non-linear dynamics. It shows that the dominant…

天体物理学 · 物理学 2009-02-23 Cyril Pitrou , Jean-Philippe Uzan , Francis Bernardeau

We derive an expression for the angular power spectrum of cosmic microwave background anisotropies due to gravity waves generated by a stochastic magnetic field and compare the result with current observations; we take into account the…

天体物理学 · 物理学 2016-08-30 R. Durrer , P. G. Ferreira , T. Kahniashvili
‹ 上一页 1 2 3 10 下一页 ›