Using the redshift evolution of the Lyman-$\alpha$ effective opacity as a probe of dark matter models

Abstract

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 ${\tau }_{\mathrm{eff}}(z)$ from the Lyman-$\alpha$ data as a discriminator between dark matter models that differ from the $\Lambda$CDM model on small scales. We consider the thermal warm dark matter (WDM) and the ultra-light axion (ULA) models for the following set of parameters: the mass of ULA, $m_a\simeq 10^{-24}–5\times 10^{-22}\mathrm{eV}$ and WDM mass, $m_{\mathrm{wdm}}=0.1–4.6\mathrm{keV}$. We simulate the line-of-sight HI density and velocity fields using semi-analytic methods. The simulated effective optical depth for the alternative dark matter models diverges from the $\Lambda$CDM model for $z\gtrsim 3$, which provides a meaningful probe of the matter power at small scales. Using likelihood analysis, we compare the simulated data with the high-resolution Lyman-$\alpha$ forest data in the redshift range $2<z<4.2$. The analysis yields the following 1$\sigma$ bounds on dark matter masses: $m_{\mathrm{wdm}}>0.7\mathrm{keV}$ and $m_{\mathrm{a}}>2\times 10^{-23}\mathrm{eV}$. To further test the efficacy of our proposed method, we simulate synthetic data sets compatible with the $\Lambda$CDM model in the redshift range $2\le z\le 6.5$ and compare with theory. The 1$\sigma$ bounds obtained are significantly tighter: $m_{\mathrm{wdm}}>1.5\mathrm{keV}$ and $m_{\mathrm{a}}>7\times 10^{-23}\mathrm{eV}$. Although our method provides an alternative way of constraining dark matter models, we note that these bounds are weaker than those obtained by high-resolution hydrodynamical simulations.

accepted for publication in JCAP

References in corpus (30)

• Ultralight scalars as cosmological dark matter
• Too big to fail? The puzzling darkness of massive Milky Way subhaloes
• Improved Dark Energy Constraints from ~100 New CfA Supernova Type Ia Light Curves
• Supernova Constraints and Systematic Uncertainties from the First 3 Years of the Supernova Legacy Survey
• Baryon Acoustic Oscillations in the Lyα forest of BOSS DR11 quasars
• Baryon Acoustic Oscillations in the Ly-α forest of BOSS quasars
• Results from a Low-Energy Analysis of the CDMS II Germanium Data
• A search for ultra-light axions using precision cosmological data
• First Dark Matter Results from the XENON100 Experiment
• Can sterile neutrinos be the dark matter?
• Strong bound on canonical ultra-light axion dark matter from the Lyman-alpha forest
• Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01
• Axion dark matter, solitons, and the cusp-core problem
• Too Big to Fail in the Local Group
• Lyman-alpha Constraints on Ultralight Scalar Dark Matter: Implications for the Early and Late Universe
• A Direct Precision Measurement of the Intergalactic Lyman-alpha Opacity at 2<z<4.2
• Constraints on the Dark Matter Particle Mass from the Number of Milky Way Satellites
• Realistic sterile neutrino dark matter with keV mass does not contradict cosmological bounds
• Ultra-Light Scalar Fields and the Growth of Structure in the Universe
• Dark energy and curvature from a future baryonic acoustic oscillation survey using the Lyman-alpha forest
• Constraints on decaying Dark Matter from XMM-Newton observations of M31
• The Ucsd/Keck Damped Lya Abundance Database: A Decade of High Resolution Spectroscopy
• The Keck+Magellan Survey for Lyman Limit Absorption I: The Frequency Distribution of Super Lyman Limit Systems
• The Lyman-alpha forest power spectrum from the XQ-100 Legacy Survey
• A Flat Photoionization Rate at 2<z<4.2: Evidence for a Stellar-Dominated UV Background and Against a Decline of Cosmic Star Formation Beyond z~3
• A combined analysis of 3D Weak Lensing, Lyman-alpha forest and WMAP year three data
• Constraining warm dark matter with cosmic shear power spectra
• Galactic Signatures of Decaying Dark Matter
• Constraints on nature of ultra light dark matter particles with 21cm forest
• Warm dark matter model with a few keV mass is bad for the too-big-to-fail problem

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