Related papers: 21-cm fluctuations from primordial magnetic fields
Primordial magnetic fields (PMFs) can seed additional small-scale matter fluctuations, leading to the formation of dense, early-collapsing dark matter structures known as minihalos. These minihalos may dramatically amplify the dark matter…
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…
Scalar modifications of gravity have an impact on the growth of structure. Baryon and Cold Dark Matter (CDM) perturbations grow anomalously for scales within the Compton wavelength of the scalar field. In the late time Universe when…
We propose a method of measuring extremely weak magnetic fields in the intergalactic medium prior to and during the epoch of cosmic reionization. The method utilizes the Larmor precession of spin-polarized neutral hydrogen in the triplet…
We present the newest statistical and numerical analysis of the matter and cosmic microwave background power spectrum with effects of the primordial magnetic field (PMF) included. New limits to the PMF strength and power spectral index are…
The cosmic 21 cm signal is set to revolutionise our understanding of the early Universe, allowing us to probe the 3D temperature and ionisation structure of the intergalactic medium (IGM). It will open a window onto the unseen first…
The true nature of primordial magnetic fields (PMFs) and their role in the formation of galaxies still remains elusive. To shed light on these unknowns, we investigate their impact by varying two sets of properties: (i) accounting for the…
We present the first constraints on primordial magnetic fields from the Lyman-$\alpha$ forest using full cosmological hydrodynamic simulations. At the scales and redshifts probed by the data, the flux power spectrum is extremely sensitive…
In this paper, we investigate the effects of helical primordial magnetic fields (PMFs) on the cosmic microwave background (CMB) reduced bispectrum. We derive the full three-point statistics of helical magnetic fields and numerically…
Next generation observatories will enable us to study the first billion years of our Universe in unprecedented detail. Foremost among these are 21-cm interferometry with the HERA and the SKA, and high-$z$ galaxy observations with the James…
We describe an attempt to reconstruct the initial conditions for the formation of cosmological large-scale structure. The power spectrum of the primordial fluctuations is affected by bias, nonlinear evolution and redshift-space distortions,…
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…
We investigate the effects of the background primordial magnetic field (PMF) on the cosmic microwave background (CMB). The sound speed of the tightly coupled photon-baryon fluid is increased by the background PMF. The increased sound speed…
We consider the contribution of 3rd and 4th order terms to the power spectrum of 21 cm brightness temperature fluctuations during the epoch of reionization, which arise because the 21 cm brightness temperature involves a product of the…
We present here predictions for the spatial distribution of 21 cm brightness temperature fluctuations from high-dynamic-range simulations for AGN-dominated reionization histories that have been tested against available Lyman-alpha and CMB…
The origin of large-scale magnetic fields is an unsolved problem in cosmology. In order to overcome, a possible scenario comes from the idea that these fields emerged from a small primordial magnetic field (PMF), produced in the early…
The cosmic microwave background (CMB) polarisation and the 21 cm line fluctuations are powerful probes of cosmological reionisation. We study how the cross-correlation between the CMB polarisation (E-modes) and the 21 cm line fluctuations…
Measurements of 21 cm line fluctuations from minihalos have been discussed as a powerful probe of a wide range of cosmological models. However, previous studies have taken into account only the pixel variance, where contributions from…
Observations of the 21 cm line radiation coming from the epoch of reionization have a great capacity to study the cosmological growth of the Universe. Also, CMB polarization produced by gravitational lensing has a large amount of…
Before the universe was reionized, it was likely that the spin temperature of intergalactic hydrogen was decoupled from the CMB by UV radiation from the first stars through the Wouthuysen-Field effect. If the IGM had not yet been heated…