English
Related papers

Related papers: Enhanced Curvature Perturbation and Primordial Bla…

200 papers

The formation of primordial black holes is studied using superconformal inflationary $\alpha$-attractors. An inflaton potential is constructed with a plateau-like region which brings about the onset of an ultra slow-roll region where the…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-05 Rafid Mahbub

Primordial black holes (PBHs) are a promising candidate for dark matter, as they can form in the very early universe without invoking new particle physics. This work explores PBH formation within a curvaton scenario featuring an…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-21 Bing-Yu Su , Nan Li , Lei Feng

We consider primordial black hole (PBH) production in inflationary $\alpha$-attractors. We discuss two classes of models, namely models with a minimal polynomial superpotential as well as modulated chaotic ones that admit PBHs. We find that…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-11 Ioannis Dalianis , Alex Kehagias , George Tringas

We propose a new single field inflation model in which the usual slow-roll inflation is joined to a new period of slow-climb and slow-roll inflation through a short intermediate non-inflationary phase. We then show that primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-02 Chengjie Fu , Puxun Wu , Hongwei Yu

The production of primordial black hole (PBH) dark matter (DM) and the generation of scalar induced secondary gravitational waves by using the enhancement mechanism with a peak function in the non-canonical kinetic term in natural inflation…

General Relativity and Quantum Cosmology · Physics 2022-05-10 Qing Gao , Yungui Gong , Zhu Yi

We propose a novel scenario to produce abundant primordial black holes (PBHs) in new inflation which is a second phase of a double inflation in the supergravity frame work. In our model, some preinflation phase before the new inflation is…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-04 Masahiro Kawasaki , Alexander Kusenko , Yuichiro Tada , Tsutomu T. Yanagida

[Abridged] The primordial scalar power spectrum is well constrained on large scales, primarily by the observations of the anisotropies in the cosmic microwave background (CMB). Over the last few years, it has been recognized that a sharp…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 H. V. Ragavendra , Pankaj Saha , L. Sriramkumar , Joseph Silk

Primordial black hole (PBH) abundance limits constrain the primordial power spectrum, and hence models of inflation, on scales far smaller than those probed by cosmological observations. Single field inflation models which are compatible…

High Energy Physics - Phenomenology · Physics 2014-11-20 Amandeep S. Josan , Anne M. Green

We investigate the formation of large peaks in the inflationary curvature power spectrum from double-well potentials. In such scenarios, the initial CMB spectrum is created at large field values. Subsequently, the inflaton will cross one of…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-06 Alexandros Karam , Niko Koivunen , Eemeli Tomberg , Antonio Racioppi , Hardi Veermäe

We study the parameter space of the effective (with two scalars) models of cosmological inflation and primordial black hole (PBH) formation in the modified $(R+R^2)$ supergravity. Our models describe double inflation, whose first stage is…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-10 Ryotaro Ishikawa , Sergei V. Ketov

Primordial Black Holes (PBHs) serve as a unique probe to the physics of the early Universe, particularly inflation. In light of this, we study the formation of PBHs by the collapse of overdense perturbations generated during a model of warm…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-17 Richa Arya

In order to produce appreciable amount of primordial black holes (PBHs), the square amplitude of curvature perturbation must take a large value of $\mathcal{O}(0.01)$, namely, seven digits larger than the value observed by cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-08 Jason Kristiano , Jun'ichi Yokoyama

Primordial black holes (PBH) have been shown to arise from high peaks in the matter power spectra of multi-field models of inflation. Here we show, with a simple toy model, that it is also possible to generate a peak in the curvature power…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-01 Juan Garcia-Bellido , Ester Ruiz Morales

The primordial black hole (PBH) productions from the inflationary potential with an inflection point usually rely heavily on the fine-tuning of the model parameters. We propose in this work a new kind of the $\alpha$-attractor inflation…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-09 Chengjie Fu , Shao-Jiang Wang

Inflation provides a suitable environment for the formation of Primordial Black Holes(PBHs). In this article, we examine the formation of primordial black holes in the Mutated Hilltop inflation model coupled with the Einstein-Gauss-Bonnet…

General Relativity and Quantum Cosmology · Physics 2025-01-06 Yogesh , Abolhassan Mohammadi

We study the formation of primordial black hole (PBH) dark matter and the generation of scalar induced secondary gravitational waves (SIGWs) in a non-supersymmetric model of hybrid inflation with chaotic (polynomial-like) potential,…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-27 Waqas Ahmed , M. Junaid , Umer Zubair

Primordial black holes (PBHs) generated by gravitational collapse of large primordial overdensities can be a fraction of the observed dark matter. In this paper, we introduce a mechanism to produce a large peak in the primordial power…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-11 Matteo Braglia , Dhiraj Kumar Hazra , Fabio Finelli , George F. Smoot , L. Sriramkumar , Alexei A. Starobinsky

In this study, we investigate the formation of primordial black holes (PBHs) in a scalar field inflationary model coupled to the Gauss-Bonnet (GB) term with fractional power-law potentials. The coupling function enhances the curvature…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-16 Ali Ashrafzadeh , Kayoomars Karami

The gravitationally enhanced friction can reduce the speed of the inflaton to realize an ultra-slow-roll inflation, which will amplify the curvature perturbations. The amplified perturbations can generate a sizable amount of primordial…

General Relativity and Quantum Cosmology · Physics 2022-10-27 Li-Yang Chen , Hongwei Yu , Puxun Wu

In the curvaton scenario, the curvature perturbation is generated after inflation at the curvaton decay, which may have a prominent non-Gaussian effect. For a model with a non-trivial kinetic term, an enhanced curvature perturbation on a…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-22 Shi Pi , Misao Sasaki
‹ Prev 1 2 3 10 Next ›