Related papers: Novel constraints on non-cold (non-thermal) Dark M…
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…
Damped Ly$\alpha$ systems provide possibly the most significant evidence for early structure formation, and thus a stringent constraint on the Cold + Hot Dark Matter (CHDM) cosmology. Using the numbers of halos in N-body simulations to…
Although the Cold + Hot Dark Matter (CHDM) cosmology provides perhaps the best fit of any model to all the available data at the current epoch, CHDM produces structure at relatively low redshifts and thus could be ruled out if there were…
In this paper we update the constraints on the simple decaying cold dark matter (DCDM) model with dark radiation (DR) as decay product. We consider two different regimes of the lifetime, i.e. short-lived and long-lived, and use the most…
Dark matter (DM) as a pressureless perfect fluid provides a good fit of the standard $\Lambda$CDM model to the astrophysical and cosmological data. In this paper, we investigate two extended properties of DM: a possible time dependence of…
Isocurvature fluctuations can be generated in various scenarios in the early Universe. In particular, some specific models predict those with a blue-tilted spectrum, which is consistent with the constraints from cosmic microwave background…
The observed Lyman-$\alpha$ flux power spectrum (FPS) is suppressed on scales below $\sim~ 30~{\rm km~s}^{-1}$. This cutoff could be due to the high temperature, $T_0$, and pressure, $p_0$, of the absorbing gas or, alternatively, it could…
We present a new method of measuring the power spectrum of initial perturbations to an unprecedently small scale of $\sim$ 10$h^{-1}$ kpc. We apply this method to a sample of 4500 Ly-$\alpha$ absorbers and recover the cold dark matter (CDM)…
Dark Matter (DM) is generally assumed to be massive, cold and collisionless from the structure formation point of view. A more correct statement however is that DM indeed experiences collisional damping, but on a scale which is supposed to…
Interpreting observations of the Lyman-$\alpha$ forest flux power spectrum requires interpolation between a small number of expensive simulations. We present a Gaussian process emulator modelling the 1D flux power spectrum as a function of…
Despite efforts over several decades, direct-detection experiments have not yet led to the discovery of the dark matter (DM) particle. This has led to increasing interest in alternatives to the Lambda CDM (LCDM) paradigm and alternative DM…
The Lyman-alpha forest is a unique probe of large-scale matter density fluctuations at high redshift z > 2. We measure the one-dimensional Lyman-alpha forest power spectrum using the first data provided by the Dark Energy Spectroscopic…
The signature left in quasar spectra by the presence of neutral hydrogen in the Universe allows one to constrain the sum of the neutrino masses with improved sensitivity, with respect to laboratory experiments, and may shed a new light on…
With upcoming high-quality data from surveys such as the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) or the Dark Energy Spectroscopic Instrument (DESI), improving the theoretical modeling and gaining a deeper understanding of…
The Lyman-$\alpha$ forest offers a unique avenue for studying the distribution of matter in the high redshift universe and extracting precise constraints on the nature of dark matter, neutrino masses, and other $\Lambda$CDM extensions.…
We present new simulations of the flux power spectrum of the Lyman $\alpha$ forest as a means to investigate the effects of time-dependent dark energy on structure formation. We use a linearized parameterization of the time-dependence of…
We study the distribution of low-redshift Ly$\alpha$ clouds in a CDM model using numerical simulations including photoionization and cooling of the baryonic component. The ionizing background is found to be efficient enough to keep most of…
Lyman-$\alpha$ forest data are known to be a good probe of the small scale matter power. In this paper, we explore the redshift evolution of the observable effective optical depth $\tau_{\rm eff} (z)$ from the Lyman-$\alpha$ data as a…
The Lyman-$\alpha$ absorption spectrum associated with photons traversing the intergalactic medium allows us to probe the linear matter power spectrum down to relatively small distance scales. Finding ways of accurately evaluating…
An ultra-light bosonic particle of mass around $10^{-22}\,\mathrm{eV}/c^2$ is of special interest as a dark matter candidate, as it both has particle physics motivations, and may give rise to notable differences in the structures on highly…