Exploring the Model Dependence of MCMC-Based 21 cm Power Spectrum Parameter Constraints

Abstract

Detection and analysis of the cosmic 21 cm signal of neutral hydrogen has long been considered the most promising route towards exploration of the Epoch of Reionization (EoR). 21CMMC, a Markov Chain Monte Carlo sampler of the seminumerical simulation code 21cmFAST, has already been used in conjunction with published upper limits on the 21 cm signal from the Murchison Widefield Array, the Low Frequency Array, and the Hydrogen Epoch of Reionization Array to constrain the astrophysics of the EoR. Here, we investigate the extent to which analysis of the EoR performed using 21CMMC is dependent on the underlying seminumerical model. We used 21cmFAST to simulate two datasets of 21 cm light-cones that differ only in the algorithm used to identify ionized regions (the so-called "bubble-finding" algorithm). We then tested 21CMMC's ability to return key astrophysical parameteres when using the different bubble-finding algorithms. We find that the performance of 21CMMC depends sensitively on the agreement between the astrophysical model of our mock data and the model used for sampling. This result has important implications for the analysis of the 21 cm signal performed using 21CMMC and further motivates investigation into model-independent analysis techniques for 21 cm EoR data.

16 pages, 8 figures, submitted to AAS journals

References in corpus (33)

• Cosmology at Low Frequencies: The 21 cm Transition and the High-Redshift Universe
• An absorption profile centred at 78 megahertz in the sky-averaged spectrum
• 21cmFAST: A Fast, Semi-Numerical Simulation of the High-Redshift 21-cm Signal
• The Growth of HII Regions During Reionization
• The history of star formation in a LCDM universe
• Reionization and Cosmology with 21 cm Fluctuations
• Efficient Simulations of Early Structure Formation and Reionization
• What Next-Generation 21 cm Power Spectrum Measurements Can Teach Us About the Epoch of Reionization
• Simulations and Analytic Calculations of Bubble Growth During Hydrogen Reionization
• Inferring the astrophysics of reionization and cosmic dawn from galaxy luminosity functions and the 21-cm signal
• 21CMMC: an MCMC analysis tool enabling astrophysical parameter studies of the cosmic 21 cm signal
• Data Analysis for Precision 21 cm Cosmology
• Comparison Of Reionization Models: Radiative Transfer Simulations And Approximate, Semi-Numeric Models
• Improved Constraints on the 21 cm EoR Power Spectrum and the X-Ray Heating of the IGM with HERA Phase I Observations
• The Baryon Acoustic Oscillation Broadband and Broad-beam Array: Design Overview and Sensitivity Forecasts
• HERA Phase I Limits on the Cosmic 21-cm Signal: Constraints on Astrophysics and Cosmology During the Epoch of Reionization
• 21cmFAST v3: A Python-integrated C code forgenerating 3D realizations of the cosmic 21cm signal
• Deep learning from 21-cm tomography of the Cosmic Dawn and Reionization
• Reionization on Large Scales I: A Parametric Model Constructed from Radiation-Hydrodynamic Simulations
• 21CMMC with a 3D light-cone: the impact of the co-evolution approximation on the astrophysics of reionisation and cosmic dawn
• Interpreting LOFAR 21-cm signal upper limits at z~9.1 in the context of high-z galaxy and reionisation observations
• The accuracy of semi-numerical reionization models in comparison with radiative transfer simulations
• Exploring reionisation and high-z galaxy observables with recent multi-redshift MWA upper limits on the 21-cm signal
• AMBER: A Semi-numerical Abundance Matching Box for the Epoch of Reionization
• Machine Learning Applied to the Reionization History of the Universe in the 21 cm Signal
• Inferring the properties of the sources of reionization using the morphological spectra of the ionized regions
• Inferring Astrophysics and Dark Matter Properties from 21cm Tomography using Deep Learning
• Bayesian Model Selection with Future 21cm Observations of The Epoch of Reionisation
• 21cmSense v2: A modular, open-source 21cm sensitivity calculator
• Deep-Learning Study of the 21cm Differential Brightness Temperature During the Epoch of Reionization
• The Impact of Realistic Foreground and Instrument Models on 21cm Epoch of Reionization Experiments
• Efficient simulation of discrete galaxy populations and associated radiation fields during the first billion years
• Understanding the Impact of Semi-numeric Reionization Models when using CNNs