Primordial black hole formation in $\alpha$-attractor models: an analysis using optimized peaks theory

Abstract

In this paper, the formation of primordial black holes (PBHs) is reinvestigated using inflationary $\alpha$-attractors. Instead of using the conventional Press-Schechter theory to compute the abundance, the optimized peaks theory is used, which was developed in Ref. \cite{Yoo:2018kvb,Yoo:2020dkz}. This method takes into account how curvature perturbations play a rôle in modifying the mass of primordial black holes. Analyzing the model proposed in \cite{Mahbub:2019uhl} it is seen that the horizon mass of the collapsed Hubble patch is larger by $\mathcal{O}(10)$ compared to the usual computation. Moreover, PBHs can be formed from curvature power spectrum, ${\mathcal{P}}_{\zeta }(k)$, peaked at lower values using numerically favored threshold overdensities. As a result of the generally larger masses predicted, the peak of the power spectrum can be placed at larger $k$ modes than that is typical with which potential future constraints on the primordial power spectrum through gravitational waves (GWs) can be evaded.

13 pages, 8 captioned figures; some computational errors have been corrected, leading to different results compared to the version 1 preprint; accepted for publication in PRD

References in corpus (11)

• Primordial Black Holes as Dark Matter: Recent Developments
• Primordial Black Holes as a dark matter candidate
• Calculating the mass spectrum of primordial black holes
• Ultra slow-roll inflation demystified
• Minimally Parametric Power Spectrum Reconstruction from the Lyman-alpha Forest
• The power spectrum on small scales: Robust constraints and comparing PBH methodologies
• Effect of nonlinearity between density and curvature perturbations on the primordial black hole formation
• Primordial black holes as dark matter and gravitational waves from bumpy axion inflation
• Threshold of Primordial Black Hole Formation in Nonspherical Collapse
• Primordial black hole formation in inflationary $\alpha$-attractor models
• Window function dependence of the novel mass function of primordial black holes

Cited by in corpus (4)

• Primordial black holes and induced gravitational waves from double-pole inflation
• Inflation, SUSY breaking, and primordial black holes in modified supergravity coupled to chiral matter
• Gravitational waves from primordial black hole dominance: The effect of inflaton decay rate
• Primordial black holes from the perturbations in the inflaton potential in peak theory