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Related papers: Primordial Non-Gaussianity and Reionization

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Fluctuations with wavelengths larger than the volume of a galaxy survey affect the measurement of the galaxy power spectrum within the survey itself. In the presence of local Primordial Non- Gaussianities (PNG), in addition to the…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Emanuele Castorina , Azadeh Moradinezhad Dizgah

The 21cm background from the epoch of reionization is a promising cosmological probe: line-of-sight velocity fluctuations distort redshift, so brightness fluctuations in Fourier space depend upon angle, which linear theory shows can…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-17 Paul R. Shapiro , Yi Mao , Ilian T. Iliev , Garrelt Mellema , Kanan K. Datta , Kyungjin Ahn , Jun Koda

Primordial fluctuations in the cosmic density are usually assumed to take the form of a Gaussian random field that evolves under the action of gravitational instability. In the early stages, while they have low amplitude, the fluctuations…

Astrophysics · Physics 2009-11-07 Peter Watts , Peter Coles

The cross-correlation between high redshift galaxies and 21 cm emission from the high redshift intergalactic medium (IGM) promises to be an excellent probe of the Epoch of Reionization (EoR). On large scales, the 21 cm and galaxy fields are…

We present the first results from SPHINX-MHD, a suite of cosmological radiation-magnetohydrodynamics simulations designed to study the impact of primordial magnetic fields (PMFs) on galaxy formation and the evolution of the intergalactic…

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…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-17 Girish Kulkarni , Tirthankar Roy Choudhury , Ewald Puchwein , Martin G. Haehnelt

Local primordial non-Gaussianity (LPNG) couples long-wavelength cosmological fluctuations to the short-wavelength behavior of galaxies. This coupling is encoded in bias parameters including $b_{\phi}$ and $b_{\delta\phi}$ at linear and…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-11 James M. Sullivan , Shi-Fan Chen

The Planck CMB experiment has delivered the best constraints so far on primordial non-Gaussianity, ruling out early-Universe models of inflation that generate large non-Gaussianity. Although small improvements in the CMB constraints are…

Primordial non-Gaussianity is one of the most powerful probes of the inflationary epoch. The particle spectrum relevant to inflation, including masses and spins, is encoded in the precise form of statistical correlations of the adiabatic…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Eugene Chen , Daniel Green , Vincent S. H. Lee

Primordial non-Gaussianities (PNGs) are imprints in the initial density field sourced by the dynamics of inflation. These dynamics can induce scale dependence, oscillations, and other features in the primordial bispectrum. We analyze a…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-24 Dhayaa Anbajagane , Hayden Lee

Spatial dependence in the statistics of redshifted 21cm fluctuations promises to provide the most powerful probe of the reionisation epoch. In this paper we consider the second and third moments of the redshifted 21cm intensity distribution…

Astrophysics · Physics 2015-06-24 Stuart Wyithe , Miguel Morales

We explore possibility of using the three dimensional bispectra of the Ly-alpha forest and the redshifted 21-cm signal from the post-reionization epoch to constrain primordial non-Gaussianity. Both these fields map out the large scale…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-04 Tapomoy Guha Sarkar , Dhiraj Kumar Hazra

Thanks to the rapid progress in precision cosmology in the last few years, we now have access to physical observables that may constrain the theory of inflation through the non-Gaussianity (NG) signatures in the cosmic microwave background…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-19 Xinghai Zhao , Yuexing Li , Sarah Shandera , Donghui Jeong

We study the signature of primordial non-Gaussianity imprinted on the power spectrum of the 21-cm line differential brightness temperature during dark ages. Employing the perturbative treatment of gravitational clustering, we quantitatively…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-24 Daisuke Yamauchi

In light of the recent inference of a high optical depth to Thomson scattering, tau, from the WMAP data we investigate the effects of extended periods of partial ionization and ask if the value of tau inferred by assuming a single sharp…

Astrophysics · Physics 2009-06-15 Gilbert Holder , Zoltan Haiman , Manoj Kaplinghat , Lloyd Knox

We present new constraints on the local-type primordial non-Gaussianity parameter, $f_\mathrm{NL}^\mathrm{local}$, through analysis of the scale-dependent bias effect on the cosmic infrared background (CIB). To avoid biases from galactic…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-06 Joseph Thornton , Fiona McCarthy , Carmen Embil Villagra , Blake D. Sherwin

High-precision constraints on primordial non-Gaussianity (PNG) will significantly improve our understanding of the physics of the early universe. Among all the subtleties in using large scale structure observables to constrain PNG,…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-10 E. Di Dio , H. Perrier , R. Durrer , G. Marozzi , A. Moradinezhad Dizgah , J. Noreña , A. Riotto

Primordial non-Gaussianity is a potentially powerful discriminant of the physical mechanisms that generated the cosmological fluctuations observed today. Any detection of non-Gaussianity would have profound implications for our…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Vincent Desjacques , Uros Seljak

The large-scale CMB B-mode polarization is the direct probe to the low frequency primordial gravitational wave signal. However, unambiguous measurement of this signal requires a precise understanding of the possible contamination. One such…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-06 Suvodip Mukherjee , Sourabh Paul , Tirthankar Roy Choudhury

We analyze the shape and amplitude of oscillatory features in the primordial power spectrum and non-Gaussianity induced by periodic production of heavy degrees of freedom coupled to the inflaton $\phi$. We find that non-adiabatic production…

High Energy Physics - Theory · Physics 2017-11-15 Raphael Flauger , Mehrdad Mirbabayi , Leonardo Senatore , Eva Silverstein