arXiv subjects

M. Ferricha-Alami

Publications and source records attributed to M. Ferricha-Alami.

3 recordsLinked to original sources

arXiv2024

Insights into Gravitinos Abundance, Cosmic Strings and Stochastic Gravitational Wave Background

In this paper, we investigate D-term inflation within the framework of supergravity, employing the minimal K\"{a}hler potential. Following previous studies that revealed that this model can overcome the $\eta$-problem found in F-term models, we explore reheating dynamics and gravitino production, emphasizing the interplay between reheating temperature, spectral index, and gravitino abundance. Our analysis indicates that gravitino production is sensitive to the equation of state during reheating, affecting the reheating temperature and subsequent dark matter relic density. Furthermore, we analyze gravitational waves generated by cosmic strings, providing critical constraints on early Universe dynamics and cosmic string properties, the energy scales of both inflation and string formation influence the stochastic gravitational wave background (SGWB) generated by these cosmic strings.

astro-ph.CO↗

arXiv2023

Dark matter via Baryogenesis: Affleck-Dine Mechanism in the Minimal Supersymmetric Standard Model

We conducted an investigation into Affleck-Dine baryogenesis within the context of D-term inflation, specifically focusing on its relationship with a recent reheating formalism. It was found that by considering a specific reheating temperature, the observed baryon asymmetry can be accounted through Affleck-Dine baryogenesis. Additionally, the majority of gravitinos are inferred to be generated from the decay of the next-to-lightest supersymmetric particle, with Q-balls potentially serving as a source of gravitinos via NSP decay. The temperature at which decay occurs depends on the charge of the Q-balls, which is determined by the fragmentation of the Affleck-Dine condensate. Remarkably, the gravitino mass required for dark matter aligns naturally with the theoretical gravitino mass.

hep-ph↗

arXiv2022

Gravitational Waves from Preheating in Gauss-Bonnet Inflation

We study gravitational wave production in an expanding Universe during the first stages following inflation, and investigate the consequences of the Gauss-Bonnet term on the inflationary parameters for a power-law inflation model with a GB coupling term. Moreover, we perform the analyses on the preheating parameters involving the number of e-folds $N_{pre}$, and the temperature of thermalization $T_{th},$ and show that it's sensitive to the parameters $n$, and $γ$, the parameter $γ$ is proposed to connect the density energy at the end of inflation to the preheating energy density. We set a correlation of gravitational wave energy density spectrum with the spectral index $n_{s}$ detected by the cosmic microwave background experiments$.$ The density spectrum $Ω_{gw}$ shows good consistency with observation for $γ= 10^{3}$ and $10^{6}$. Our findings suggest that the generation of gravitational waves (GWs) during preheating can satisfy the constraints from Planck's data.

gr-qc↗