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Related papers: Magnification bias as a novel probe for primordial…

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In the pre-recombination era, cosmological density fluctuations can naturally generate magnetic fields through Thomson scatterings. In previous studies, only the magnetic field generation from the initially-adiabatic fluctuations has been…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Satoshi Maeda , Keitaro Takahashi , Kiyotomo Ichiki

One of the most direct routes for investigating the geometry of the Universe is provided by the numbers of strongly magnified gravitationally lensed galaxies as compared with those that are either weakly magnified or de-magnified. In the…

Astrophysics · Physics 2009-10-30 A W Blain

We show that the relatively strong magnetic fields ($\ge 1 \mu$G) in high redshift objects can be explained by the combined action of an evolving protogalactic fluctuation and electrodynamic processes providing the magnetic seed fields.…

Astrophysics · Physics 2007-05-23 Harald Lesch , Masashi Chiba

We describe a new method for measuring galaxy magnification due to weak gravitational lensing. Our method makes use of a tight scaling relation between galaxy properties that are modified by gravitational lensing, such as apparent size, and…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-07 Eric M. Huff , Genevieve J. Graves

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…

Astrophysics · Physics 2016-08-30 Seoktae Koh , Chul H. Lee

We performed cosmological, magneto-hydrodynamical simulations to follow the evolution of magnetic fields in galaxy clusters, exploring the possibility that the origin of the magnetic seed fields are galactic outflows during the star-burst…

Astrophysics · Physics 2009-11-13 J. Donnert , K. Dolag , H. Lesch , E. Müller

Primordial magnetic fields generated in the early universe are subject of considerable investigation, and observational limits on their strength are required to constrain the theory. Due to their impact on the reionization process, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Dominik R. G. Schleicher , Francesco Miniati

The surface density of populations of galaxies with steep/shallow source counts is increased/decreased by gravitational lensing magnification. These effects are usually called `magnification bias' and `depletion' respectively. However, if…

Astrophysics · Physics 2009-11-07 Andrew W. Blain

Magnetic fields are one of most concealed components of the universe. They are observed as part of the intergalactic medium and on galaxy cluster scales, however their origin and evolution is unclear. In this work we use the IllustrisTNG…

Astrophysics of Galaxies · Physics 2023-05-04 Agustín M. Rodríguez-Medrano , Federico A. Stasyszyn , Dante J. Paz , Volker Springel

Cluster gravitational lensing surveys like the Hubble Space Telescope Frontier Fields survey will detect distant galaxies 10-50 times fainter than any yet discovered. Using these surveys to measure the luminosity function of such faint,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Anson D'Aloisio , Priyamvada Natarajan , Paul R. Shapiro

The Cosmic Microwave Background (CMB) radiation lensing is a promising tool to study the physics of early universe. In this work we probe the imprints of deviations from isotropy and scale invariance of primordial curvature perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-01 Farbod Hassani , Shant Baghram , Hassan Firouzjahi

We present the clustering of galaxy clusters as a useful addition to the common set of cosmological observables. The clustering of clusters probes the large-scale structure of the Universe, extending galaxy clustering analysis to the…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-03 Annalisa Mana , Tommaso Giannantonio , Jochen Weller , Ben Hoyle , Gert Huetsi , Barbara Sartoris

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…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Nanoom Lee , Yacine Ali-Haimoud

In addition to the intrinsic clustering of galaxies themselves, the spatial distribution of galaxies observed in surveys is modulated by the presence of weak lensing due to matter in the foreground. This effect, known as magnification bias,…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-09 Lukas Wenzl , Shi-Fan Chen , Rachel Bean

We explore the ways in which primordial magnetic fields influence the thermal and ionization history of the post-recombination universe. After recombination the universe becomes mostly neutral resulting also in a sharp drop in the radiative…

Astrophysics · Physics 2008-11-26 Shiv K. Sethi , Kandaswamy Subramanian

In this thesis, we aim to investigate the mechanisms underlying the genesis of magnetic fields in the Universe and explore their potential in addressing the matter-antimatter asymmetry. We construct consistent models that generate the…

General Relativity and Quantum Cosmology · Physics 2024-03-21 Ashu Kushwaha

The primordial density fluctuation inevitably couples to all forms of matter via loop corrections and depends on the ambient conditions while inflation was ongoing. This gives us an opportunity to observe processes which were in progress…

Astrophysics · Physics 2009-08-24 David Seery

We discuss several effects due to lensing of ultra high energy cosmic rays by the regular component of the galactic magnetic field. Large flux magnification around caustics can be a significant source of clustering in the arrival directions…

Astrophysics · Physics 2009-10-31 Diego Harari , Silvia Mollerach , Esteban Roulet

A primordial magnetic field could be responsible for the observed magnetic fields of the galaxies. One possibility is that such a primordial field is generated at the electroweak phase transition because of the fluctuations in the Higgs…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kari Enqvist

Gravitational lensing can be used to analyze the redshift distribution of faint galaxies. In particular the magnification bias modifies locally the galaxy number density of lensed sources observed in lensing clusters. This depletion area…

Astrophysics · Physics 2007-05-23 Y. Mellier