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Related papers: Revised $f_{\rm NL}$ parameter in Curvaton Scenari…

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We investigate density perturbations sourced by a curvaton with a generic energy potential. The key feature of a curvaton potential which deviates from a quadratic is that the curvaton experiences a non-uniform onset of its oscillation.…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-12 Masahiro Kawasaki , Takeshi Kobayashi , Fuminobu Takahashi

We study the curvaton scenario using gauge-invariant second order perturbation theory and solving the governing equations numerically. Focusing on large scales we calculate the non-linearity parameter f_nl in the two-fluid curvaton model…

Astrophysics · Physics 2009-11-11 Karim A. Malik , David H. Lyth

A $\delta N$ formalism is used to study the non-Gaussianity of the primordial curvature perturbation on an uniform density hypersurfaces generated by the warm inflation for the first time. After introducing the framework of the warm…

General Relativity and Quantum Cosmology · Physics 2016-04-01 Xiao-Min Zhang , Hong-Yang Ma , Peng-Cheng Chu , Jun-Ting Liu , Jian-Yang Zhu

In this paper, we will use $\delta \mathcal{N}$-formalism to calculate the primordial curvature perturbation for the curvaton model with a Lagrange multiplier field. We calculate the non-linearity parameters $f_{NL}$ and $g_{NL}$ in the…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-27 Chao-Jun Feng , Xin-Zhou Li

We show that the local type non-Gaussianity in a class of curvaton models is suppressed, i.e. the non-linearity parameters f_{NL} and those related with higher order statistics can be at most O(1), even if the curvaton energy density is…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-25 Kyohei Mukaida , Kazunori Nakayama , Masahiro Takimoto

The generation of non-gaussianity is studied in a three fluid curvaton model. By utilizing second order perturbation theory we derive general formulae for the large scale temperature fluctuation and non-gaussianity parameter, $f_{NL}$, that…

Astrophysics · Physics 2009-07-30 Tuomas Multamaki , Jani Sainio , Iiro Vilja

We discuss observational consequences of the curvaton scenario, which naturally appears in the context of the simplest model of chaotic inflation in supergravity. The non-gaussianity parameter f_NL in this scenario can take values in the…

High Energy Physics - Theory · Physics 2015-05-20 Vittoria Demozzi , Andrei Linde , Viatcheslav Mukhanov

We characterise the primordial perturbations produced due to both inflaton and curvaton fluctuations in models where the curvaton has a quadratic, cosine or hyperbolic potential, and the inflaton potential is characterised by the usual…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 José Fonseca , David Wands

We investigate the non-Gaussianity of primordial curvature perturbation in the modulated reheating scenario where the primordial perturbation is generated due to the spacial fluctuation of the inflaton decay rate to radiation. We use the…

Astrophysics · Physics 2008-11-26 Teruaki Suyama , Masahide Yamaguchi

We study non-Gaussianity of density perturbations generated by an axionic curvaton, focusing on the case that the curvaton sits near the hilltop of the potential during inflation. Such hilltop curvatons can generate a red-tilted density…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-15 Masahiro Kawasaki , Takeshi Kobayashi , Fuminobu Takahashi

Inflating curvaton can create curvature perturbation when the curvaton density is slowly varying. Using the delta-N formalism, we discuss the evolution of the curvature perturbation during curvaton inflation and find analytic formulation of…

High Energy Physics - Phenomenology · Physics 2013-06-26 Seishi Enomoto , Kazunori Kohri , Tomohiro Matsuda

We consider curvaton models with potentials that depart slightly from the quadratic form. We show that although such a small departure does not modify significantly the Gaussian part of the curvature perturbation, it can have a pronounced…

Astrophysics · Physics 2008-11-26 Kari Enqvist , Sami Nurmi

We show how to build a curvaton inflationary model motivated by scale-dependent non-Gaussianities of cosmological perturbations. In particular, we study the change of sign in the $f_{NL}$ parameter as a function of the curvaton field value…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-31 L. F. Guimarães , F. T. Falciano

We discuss the signatures of non-Gaussianity in the curvaton model where the potential includes also a non-quadratic term. In such a case the non-linearity parameter f_NL can become very small, and we show that non-Gaussianity is then…

Astrophysics · Physics 2011-07-13 Kari Enqvist , Tomo Takahashi

We study a model where two scalar fields, that are subdominant during inflation, decay into radiation some time after inflation has ended but before primordial nucleosynthesis. Perturbations of these two curvaton fields can be responsible…

Astrophysics · Physics 2008-06-05 Jussi Valiviita , Hooshyar Assadullahi , David Wands

We analyze the non-Gaussianity for primordial curvature perturbations generated in multi-scalar slow-roll inflation model including the model with non-separable potential by making use of $\delta N$ formalism. Many authors have investigated…

Astrophysics · Physics 2009-06-23 Shuichiro Yokoyama , Teruaki Suyama , Takahiro Tanaka

We use the delta N -formalism to investigate the non-Gaussianity of the primordial curvature perturbation in the curvaton scenario for the origin of structure. We numerically calculate the full probability distribution function allowing for…

Astrophysics · Physics 2010-04-06 Misao Sasaki , Jussi Valiviita , David Wands

In this paper we consider how non-Gaussianity of the primordial density perturbation and the amplitude of gravitational waves from inflation can be used to determine parameters of the curvaton scenario for the origin of structure. We show…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-22 José Fonseca , David Wands

We investigate the curvaton dynamics and the non-linearity parameters in curvaton model with potential slightly deviating from the quadratic form in detail. The non-linearity parameter $g_{NL}$ will show up due to the curvaton…

High Energy Physics - Theory · Physics 2009-03-27 Qing-Guo Huang , Yi Wang

We provide a model in which both the inflaton and the curvaton are obtained from within the minimal supersymmetric Standard Model, with known gauge and Yukawa interactions. Since now both the inflaton and curvaton fields are successfully…

High Energy Physics - Phenomenology · Physics 2012-03-14 Anupam Mazumdar , Seshadri Nadathur
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