Quintessential Kination and Thermal Production of Gravitinos and Axinos

Abstract

The impact of a kination-dominated phase generated by a quintessential exponential model on the thermal abundance of gravitinos and axinos is investigated. We find that their abundances become proportional to the transition temperature from the kination to the radiation era; since this temperature is significantly lower than the initial ("reheating") temperature, the abundances decrease with respect to their values in the standard cosmology. For values of the quintessential energy-density parameter close to its upper bound, at the eve of nucleosynthesis, we find the following: (i) for unstable gravitinos, the gravitino constraint is totally evaded; (ii) If the gravitino is stable, its thermal abundance is not sufficient to account for the cold dark matter of the universe; (iii) the thermal abundance of axinos can satisfy the cold dark matter constraint for values of the initial temperature well above those required in the standard cosmology. A novel calculation of the axino production rate by scatterings at low temperature is also presented.

Published Version

References in corpus (9)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Big-Bang Nucleosynthesis and Gravitino
• Thermal production of gravitinos
• Cosmological implications of supersymmetric axion models
• Inflationary Cosmology Connecting Dark Energy and Dark Matter
• Determining Reheating Temperature at Colliders with Axino or Gravitino Dark Matter
• Electroweak Contributions to Thermal Gravitino Production
• Determining Reheating Temperature at LHC with Axino or Gravitino Dark Matter
• Braneworld Quintessential Inflation and Sum of Exponentials Potentials

Cited by in corpus (2)

• Upper Limits on the Peccei-Quinn Scale and on the Reheating Temperature in Axino Dark Matter Scenarios
• Quintessential Kination and Thermal Production of SUSY e-WIMPs