Balmer breaks in simulated galaxies at z>6

Abstract

Photometric observations of the spectroscopically confirmed $z\approx 9.1$ galaxy MACS1149-JD1 have indicated the presence of a prominent Balmer break in its spectral energy distribution, which may be interpreted as due to very large fluctuations in its past star formation activity. In this paper, we investigate to what extent contemporary simulations of high-redshift galaxies produce star formation rate variations sufficiently large to reproduce the observed Balmer break of MACS1149-JD1. We find that several independent galaxy simulations are unable to account for Balmer breaks of the inferred size, suggesting that MACS1149-JD1 either must be a very rare type of object or that our simulations are missing some key ingredient. We present predictions of spectroscopic Balmer break strength distributions for $z\approx 7-9$ galaxies that may be tested through observations with the upcoming James Webb Space Telescope and also discuss the impact that various assumptions on dust reddening, Lyman continuum leakage and deviations from a standard stellar initial mass function would have on the results.

arXiv comment11 pages, 8 figures. Accepted for publication in MNRAS

References in corpus (35)

• On the variation of the Initial Mass Function
• The cosmological simulation code GADGET-2
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• Starburst99: Synthesis Models for Galaxies with Active Star Formation
• Dust Grain Size Distributions and Extinction in the Milky Way, LMC, and SMC
• EAZY: A Fast, Public Photometric Redshift Code
• A Simple Model for the Absorption of Starlight by Dust in Galaxies
• GIZMO: A New Class of Accurate, Mesh-Free Hydrodynamic Simulation Methods
• FIRE-2 Simulations: Physics versus Numerics in Galaxy Formation
• Binary Population and Spectral Synthesis Version 2.1: construction, observational verification and new results
• Adaptive Refinement Tree - a new high-resolution N-body code for cosmological simulations
• A Remarkably Luminous Galaxy at z=11.1 Measured with Hubble Space Telescope Grism Spectroscopy
• Optimization of Starburst99 for Intermediate-Age and Old Stellar Populations
• The 2013 Release of Cloudy
• Lyman-alpha and CIII] Emission in z=7-9 Galaxies: Accelerated Reionization Around Luminous Star Forming Systems?
• The Most Luminous z~9-10 Galaxy Candidates yet Found: The Luminosity Function, Cosmic Star-Formation Rate, and the First Mass Density Estimate at 500 Myr
• Rest-frame ultraviolet-to-optical spectral characteristics of extremely metal-poor and metal-free galaxies
• The spectral evolution of the first galaxies. I. James Webb Space Telescope detection limits and color criteria for population III galaxies
• A highly magnified candidate for a young galaxy seen when the Universe was 500 Myrs old
• The role of stellar feedback in the formation of galaxies
• Fluctuating feedback-regulated escape fraction of ionizing radiation in low-mass, high-redshift galaxies
• Predicted UV properties of very metal-poor starburst galaxies
• Radiative feedback and the low efficiency of galaxy formation in low-mass haloes at high redshift
• Precise Strong Lensing Mass Modeling of Four Hubble Frontier Fields Clusters and a Sample of Magnified High-Redshift Galaxies
• Simulating galaxies in the reionization era with FIRE-2: galaxy scaling relations, stellar mass functions, and luminosity functions
• The Stellar Initial Mass Function in Early-Type Galaxies from Absorption Line Spectroscopy. III. Radial Gradients
• On the Evolutionary History of Stars and their Fossil Mass and Light
• Dust attenuation, dust emission, and dust temperature in galaxies at z>=5: a view from the FIRE-2 simulations
• Introducing the FirstLight project: UV luminosity function and scaling relations of primeval galaxies
• FirstLight II: Star formation rates of primeval galaxies from z=5-15
• HST Grism Observations of a Gravitationally Lensed Redshift 10 Galaxy
• FirstLight III: Rest-frame UV-optical spectral energy distributions of simulated galaxies at cosmic dawn
• Young Galaxy Candidates in the Hubble Frontier Fields IV. MACS J1149.5+2223
• Nebular line emission from z > 7 galaxies in cosmological simulations: rest-frame UV to Optical lines
• Probing Cosmic Dawn: Modelling the Assembly History, SEDs, and Dust Content of Selected $z\sim 9$ Galaxies

Cited by in corpus (8)

• RUBIES: Evolved Stellar Populations with Extended Formation Histories at $z\sim 7-8$ in Candidate Massive Galaxies Identified with JWST/NIRSpec
• Inferring the Age of the Universe with Globular Clusters
• A population of faint, old, and massive quiescent galaxies at 3 < z < 4 revealed by JWST NIRSpec Spectroscopy
• Probing Cosmic Dawn : Ages and Star Formation Histories of Candidate $z\ge$9 Galaxies
• Interpreting the Spitzer/IRAC Colours of 7<z<9 Galaxies: Distinguishing Between Line Emission and Starlight Using ALMA
• Possible Systematic Rotation in the Mature Stellar Population of a $z=9.1$ Galaxy
• The Effect of Warm Dark Matter on Early Star Formation Histories of Massive Galaxies: Predictions from the CROC Simulations
• Taking a Break at Cosmic Noon: Continuum-selected Low-mass Galaxies Require Long Burst Cycles