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Related papers: Signature of a Cosmic String Wake at $z=3$

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Three-dimensional ridgelet statistics are used to search for the signals of cosmic string wakes in the distribution of dark matter. We compare N-body simulations of the dark matter distribution in cosmological models with and without a…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-27 Samuel Laliberte , Robert Brandenberger , Disrael Camargo Neves da Cunha

We discuss the signature of a cosmic string wake in 21cm redshift surveys. Since 21cm surveys probe higher redshifts than optical large-scale structure surveys, the signatures of cosmic strings are more manifest in 21cm maps than they are…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Robert H. Brandenberger , Rebecca J. Danos , Oscar F Hernandez , Gilbert P. Holder

A cosmic string wake produces a distinct non-Gaussian signal in 21-cm intensity maps at redshifts above that of reionization. While the string signal is (locally) larger in amplitude than the signal of the Gaussian fluctuations of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-05 David Maibach , Robert Brandenberger , Devin Crichton , Alexandre Refregier

We study the stability of cosmic string wakes against the disruption by the dominant Gaussian fluctuations which are present in cosmological models. We find that for a string tension given by $G \mu = 10^{-7}$ wakes remain locally stable…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-16 Robert H. Brandenberger , Oscar F. Hernández , Disrael C. N. da Cunha

Cosmic strings are generically predicted in many extensions of the Standard Model of particle physics. We propose a new avenue for detecting cosmic strings through their effect on the filamentary structure in the cosmic web. Using…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-11 M. A. Fernandez , Simeon Bird , Yanou Cui

The analysis of the 21 cm signature of cosmic string wakes is extended in several ways. First we consider the constraints on $G\mu$ from the absorption signal of shock heated wakes laid down much later than matter radiation equality.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Oscar F. Hernandez , Robert H. Brandenberger

We study the distribution of dark matter in the nonlinear regime in a model in which the primordial fluctuations include, in addition to the dominant primordial Gaussian fluctuations generated by the standard $\Lambda CDM$ cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-24 Disrael Cunha , Joachim Harnois-Deraps , Robert Brandenberger , Adam Amara , Alexandre Refregier

In previous works we discussed the 21 cm signature of a single cosmic string wake. However the 21 cm brightness temperature is influenced by a network of cosmic string wakes, and not one single wake. In this work we consider the signal from…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-23 Oscar F. Hernández

The baryon density enhancement in cosmic string wakes leads to a stronger coupling of the spin temperature to the gas kinetic temperate inside these string wakes than in the intergalactic medium (IGM). The Wouthuysen Field (WF) effect has…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-24 Oscar F. Hernandez

We investigate a static, cylindrically symmetric cosmic string on the brane without a perturbative approximation. We find there could be a (large) enhancement of the (effective) string tension when the energy density at the center of the…

High Energy Physics - Theory · Physics 2023-04-12 Chia-Min Lin

We study the accretion of cold and hot dark matter onto a cosmic string wake using a high-resolution numerical simulation. We verify previous analytical calculations predicting the radius of bound matter around wakes and inflow velocities…

Astrophysics · Physics 2016-08-25 Andrew T. Sornborger

In this paper we study the footprint of cosmic string as the topological defects in the very early universe on the cosmic microwave background radiation. We develop the method of level crossing analysis in the context of the well-known…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-21 M. Sadegh Movahed , Shahram Khosravi

ABSRACT: We review recent progress on testing the hypothesis of the existence of cosmic string perturbations in microwave background maps. Using an analytical model for the string network we show that the predicted amplitude and spectrum of…

Astrophysics · Physics 2009-09-25 Leandros Perivolaropoulos , Richhild Moessner , Robert Brandenberger

We calculate the contribution of cosmic strings arising from a phase transition in the early universe, or cosmic superstrings arising from brane inflation, to the cosmic 21 cm power spectrum at redshifts z > 30. Future experiments can…

Astrophysics · Physics 2011-07-19 Rishi Khatri , Benjamin D. Wandelt

We use wavelet and curvelet transforms to extract signals of cosmic strings from cosmic microwave background (CMB) temperature anisotropy maps, and to study the limits on the cosmic string tension which various ongoing CMB temperature…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-21 Lukas Hergt , Adam Amara , Robert Brandenberger , Tomasz Kacprzak , Alexandre Refregier

We intend to make sets of cosmological simulations available, with a large number of different output times that may be placed side-by-side to produce a complete history of the universe stretching back to high redshift. Currently there is…

Astrophysics · Physics 2007-05-23 P. A. Thomas , H. M. P. Couchman , F. R. Pearce

We present in detail the convolutional neural network used in our previous work to detect cosmic strings in cosmic microwave background (CMB) temperature anisotropy maps. By training this neural network on numerically generated CMB…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-15 Razvan Ciuca , Oscar F. Hernández , Michael Wolman

Minkowski Functionals are a powerful tool for analyzing large scale structure, in particular if the distribution of matter is highly non-Gaussian, as it is in models in which cosmic strings contribute to structure formation. Here we apply…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Evan McDonough , Robert H. Brandenberger

We use a convolutional neural network (CNN) to study cosmic string detection in cosmic microwave background (CMB) flat sky maps with Nambu-Goto strings. On noiseless maps we can measure string tensions down to order $10^{-9}$, however when…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-03 Razvan Ciuca , Oscar F. Hernández

We calculate a signature of cosmic strings in the polarization of the cosmic microwave background (CMB). We find that ionization in the wakes behind moving strings gives rise to extra polarization in a set of rectangular patches in the sky…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Rebecca J. Danos , Robert H. Brandenberger , Gil Holder
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