Accelerating early massive galaxy formation with primordial black holes

Abstract

Recent observations with JWST have identified several bright galaxy candidates at $z\gtrsim 10$, some of which appear unusually massive (up to $\sim 10^{11}{\mathrm{M}}_{\odot }$). Such early formation of massive galaxies is difficult to reconcile with standard $\Lambda \mathrm{CDM}$ predictions, demanding very high star formation efficiency (SFE), possibly even in excess of the cosmic baryon mass budget in collapsed structures. With an idealized analysis based on linear perturbation theory and the Press-Schechter formalism, we show that the observed massive galaxy candidates can be explained with lower SFE than required in $\Lambda \mathrm{CDM}$, if structure formation is accelerated/seeded by massive ($\gtrsim 10^9{\mathrm{M}}_{\odot }$) primordial black holes (PBHs) that make a up a small fraction ($\sim 10^{-6}-10^{-3}$) of dark matter, considering existing empirical constraints on PBH parameters. We also discuss the potential observational signatures of PBH cosmologies in the JWST era. More work needs to be done to fully evaluate the viability of such PBH models to explain observations of the high-$z$ Universe.

7+2 pages, 4 figures, accepted for publication in ApJL

References in corpus (12)

• Ultralight scalars as cosmological dark matter
• Primordial Black Holes as Dark Matter: Recent Developments
• Signature of Excess Radio Background in the 21-cm Global Signal and Power Spectrum
• Primordial Black Holes Confront LIGO/Virgo data: Current situation
• An excess of small-scale gravitational lenses observed in galaxy clusters
• Supermassive black holes formed by direct collapse of inflationary perturbations
• Constraining First Star Formation with 21cm-Cosmology
• Upper limits on the mass and luminosity of Population III-dominated galaxies
• Dust in the first galaxies
• Constraining the epoch of reionization from the observed properties of the high-z Universe
• Probing isocurvature perturbations with 21-cm global signal in the light of HERA result
• Lessons on early structure formation from a mature galaxy cluster observed at cosmic noon

Cited by in corpus (6)

• Efficient Formation of Massive Galaxies at Cosmic Dawn by Feedback-Free Starbursts
• Stochastic star formation in early galaxies: JWST implications
• Alleviating the need for exponential evolution of JWST galaxies in 10${}^{10}{M}_{\odot }$ haloes at $z>10$ by a modified $\Lambda$CDM power spectrum
• A persistent excess of galaxy-galaxy strong lensing observed in galaxy clusters
• Probing the Nature of the First Galaxies with JWST and ALMA
• Primordial Black Holes from Spatially Varying Cosmological Constant Induced by Field Fluctuations in Extra Dimensions