A tale of two sites -- II: Inferring the properties of minihalo-hosted galaxies with upcoming 21-cm interferometers

Abstract

The first generation of galaxies is expected to form in minihalos, accreting gas through ${\mathrm{H}}_2$ cooling, and possessing unique properties. Although unlikely to be directly detected in UV/infrared surveys, the radiation from these molecular-cooling galaxies (MCGs) could leave an imprint in the 21-cm signal from the Cosmic Dawn. Here we quantify their detectability with upcoming radio interferometers. We generate mock 21-cm power spectra using a model for both MCGs as well as more massive, atomic-cooling galaxies (AGCs), allowing both populations to have different properties and scaling relations. The galaxy parameters are chosen so as to be consistent with: (i) high-redshift UV luminosity functions; (ii) the upper limit on the neutral fraction from QSO spectra; (iii) the Thomson scattering optical depth to the CMB; and (iv) the timing of the recent putative EDGES detection. The latter implies a significant contribution of MCGs to the Cosmic Dawn, if confirmed to be cosmological. We then perform Bayesian inference on two models including and ignoring MCG contributions. Comparing their Bayesian evidences, we find a strong preference for the model including MCGs, despite the fact that it has more free parameters. This suggests that if MCGs indeed play a significant role in the Cosmic Dawn, it should be possible to infer their properties from upcoming 21-cm power spectra. Our study illustrates how these observations can discriminate among uncertain galaxy formation models with varying complexities, by maximizing the Bayesian evidence.

12 pages, 3 figures, submitted to MNRAS, comments are welcome

References in corpus (29)

• Cosmic Star Formation History
• UV Luminosity Functions at redshifts z~4 to z~10: 10000 Galaxies from HST Legacy Fields
• Model-independent evidence in favor of an end to reionization by z~6
• A Search for Stars of Very Low Metal Abundance. VI. Detailed Abundances of 313 Metal-Poor Stars
• Efficient Simulations of Early Structure Formation and Reionization
• The Formation of Population III Binaries from Cosmological Initial Conditions
• The morphology of HII regions during reionization
• 21 cm fluctuations from inhomogeneous X-ray heating before reionization
• The Formation of the First Stars II. Radiative Feedback Processes and Implications for the Initial Mass Function
• Population III stars: hidden or disappeared ?
• 21CMMC: an MCMC analysis tool enabling astrophysical parameter studies of the cosmic 21 cm signal
• A Superbubble Feedback Model for Galaxy Simulations
• The Destruction of Cosmological Minihalos by Primordial Supernovae
• Feedback-regulated star formation and escape of LyC photons from mini-haloes during reionisation
• Suppression of H_2 Cooling in the Ultraviolet Background
• First Season MWA EoR Power Spectrum Results at Redshift 7
• Measuring the effective complexity of cosmological models
• When did Population III star formation end?
• A tale of two sites -- I: Inferring the properties of minihalo-hosted galaxies from current observations
• Unveiling the nature of dark matter with high redshift 21 cm line experiments
• The Effects of Population III X-ray and Radio Backgrounds on the Cosmological 21-cm Signal
• A photometric survey for Lyalpha-HeII dual emitters: Searching for Population III stars in high-redshift galaxies
• Bayesian Methods in Cosmology
• The impact of non-Gaussianity on the error covariance for observations of the Epoch of Reionization 21-cm power spectrum
• X-ray Background at High Redshifts from Pop III Remnants: Results from Pop III star formation rates in the Renaissance Simulations
• Finding the First Cosmic Explosions. IV. 90 - 140 M${}_{\odot }$ Pair-Instability Supernovae
• Probing the first galaxies with the SKA
• Dust in the first galaxies
• Bayesian Model Selection with Future 21cm Observations of The Epoch of Reionisation

Cited by in corpus (28)

• Improved Constraints on the 21 cm EoR Power Spectrum and the X-Ray Heating of the IGM with HERA Phase I Observations
• HERA Phase I Limits on the Cosmic 21-cm Signal: Constraints on Astrophysics and Cosmology During the Epoch of Reionization
• The Impact of the First Galaxies on Cosmic Dawn and Reionization
• Reionization and galaxy inference from the high-redshift Lyα forest
• Constraints on warm dark matter from UV luminosity functions of high-z galaxies with Bayesian model comparison
• ETHOS -- An Effective Theory of Structure Formation: Impact of Dark Acoustic Oscillations on Cosmic Dawn
• Constraining Warm Dark Matter and Pop III stars with the Global 21-cm Signal
• Cosmic Reionization May Still Have Started Early and Ended Late: Confronting Early Onset with CMB Anisotropy and 21 cm Global Signals
• LIMFAST. II. Line Intensity Mapping as a Probe of High-Redshift Galaxy Formation
• 21cmfish: Fisher-matrix framework for fast parameter forecasts from the cosmic 21-cm signal
• LIMFAST. I. A Semi-Numerical Tool for Line Intensity Mapping
• Probing Population III Initial Mass Functions with He II/H$\alpha$ Intensity Mapping
• Modelling Population III stars for semi-numerical simulations
• The First Billion Years in Seconds: An Effective Model for the 21-cm Signal with Population III Stars
• The high-redshift tail of stellar reionization in LCDM is beyond the reach of the low-$\ell$ CMB
• The EDGES measurement disfavors an excess radio background during the cosmic dawn
• Efficient exploration of reionization parameters for the upcoming 21 cm observations using a photon conserving semi-numerical model SCRIPT
• 21cmFirstCLASS II. Early linear fluctuations of the 21cm signal
• Thermal and Reionisation History within a Large-Volume Semi-Analytic Galaxy Formation Simulation
• Probing Dark Relativistic Species and Their Interactions with Dark Matter through CMB and 21cm surveys
• Efficient simulation of discrete galaxy populations and associated radiation fields during the first billion years
• Signatures of reionization feedback in the near-infrared background
• Effects of Small-Scale Absorption Systems on Neutral Islands during the Late Epoch of Reionization
• Fisher matrix forecasts on the astrophysics of galaxies during the epoch of reionisation from the 21-cm power spectra
• Efficient Modelling of Lyman-α opacity fluctuations during late reionization epoch
• Imprints of fermionic and bosonic mixed dark matter on the 21-cm signal at cosmic dawn
• Revealing the formation histories of the first stars with the cosmic near-infrared background
• The 21-cm signal from the Cosmic Dawn: metallicity dependence of high mass X-ray binaries