Related papers: High redshift signatures in the 21 cm forest due t…
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…
Understanding the nature of dark matter (DM) particles remains a pivotal challenge in modern cosmology. Current cosmological research on these phenomena primarily utilizes cosmic microwave background (CMB) observations and other late-time…
The mean spectrum and burst statistics of gravitational waves produced by a cosmological population of cosmic string loops are estimated using analytic approximations, calibrated with earlier simulations. Formulas are derived showing the…
The sky-averaged (global) 21-cm signal is a powerful probe of the intergalactic medium (IGM) prior to the completion of reionization. However, it has so far been unclear that even in the best case scenario, in which the signal is accurately…
Cosmic strings are a common prediction in many grand unified theories and a promising source of stochastic gravitational waves (GWs) from the early Universe. In this paper, we point out that the GW signal from cosmic strings produced at a…
Cosmic strings and primordial black holes (PBHs) commonly and naturally form in many scenarios describing the early universe. Here we show that if both cosmic strings and PBHs are present, their interaction leads to a range of interesting…
The H atoms inside minihalos (i.e. halos with virial temperatures T_vir < 10^4 K, in the mass range roughly from 10^4 M_sun to 10^8 M_sun) during the cosmic dark ages in a LambdaCDM universe produce a redshifted background of…
We investigate the contribution made by small loops from a cosmic string network as seeds for large-scale structure formation. We show that cosmic string loops are highly correlated with the long-string network on large scales and therefore…
We present a study of the 21-cm signal bispectrum (which quantifies the non-Gaussianity in the signal) from the Cosmic Dawn (CD). For our analysis, we have simulated the 21-cm signal using radiative transfer code GRIZZLY, while considering…
Cosmic strings appear in many well-motivated extensions to the standard model of particle physics. If they exist, an abundant population of compact objects known as cosmic string loops permeate the Universe at all times, providing a…
The radiations from the first luminous sources drive the fluctuations in the 21-cm signal at Cosmic Dawn (CD) via two dominant astrophysical processes i.e. the Ly$\alpha$ coupling and X-ray heating, making this signal highly non-Gaussian.…
We consider a population of small, high-velocity cosmic string loops. We assume the typical length of these loops is determined by the gravitational radiation scale and use the results of \cite{Polchinski:2007rg} which pointed out their…
Cosmic strings can be created in the early universe during symmetry-breaking phase transitions, such as might arise if the gauge structure of the standard model is extended by additional U(1) factors at high energies. Cosmic strings present…
We discuss the prospects to measure galaxy-cluster properties via weak lensing of 21-cm fluctuations from the dark ages and the epoch of reionization (EOR). We choose as a figure of merit the smallest cluster mass detectable through such…
Cosmic strings are one-dimensional topological defects which could have been formed in the early stages of our Universe. They triggered a lot of interest, mainly for their cosmological implications: they could offer an alternative to…
Recent observations of high redshift galaxies by the James Webb Space Telescope suggest the presence of a bright population of galaxies that is more abundant than predicted by most galaxy formation models. These observations have led to a…
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…
At the beginning of the reionization epoch, radiation sources produce fluctuations in the redshifted 21-cm background. We show that different types of sources (such as miniquasars, Pop II and III stars, supernovae, etc.) produce distinct…
We study the signal of cosmic string wakes present before the time of reionization in the cross-correlation signal of 21-cm redshift and B-mode CMB polarization maps. The specific non-Gaussian signal of strings in the position space…
The 21-cm forest is a sensitive probe for the early heating process and small-scale structures during the epoch of reionization (EoR), to be realized with the upcoming Square Kilometre Array (SKA). Its detection relies on the availability…