skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A Rich Tapestry: Supersymmetric Axions, Dark Radiation, and Inflationary Reheating

Authors:
; ;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1156537
Report Number(s):
FERMILAB-PUB-14-233-A-PPD
arXiv eprint number arXiv:1407.4110
DOE Contract Number:
AC02-07CH11359
Resource Type:
Journal Article
Country of Publication:
United States
Language:
English

Citation Formats

Queiroz, Farinaldo S., Sinha, Kuver, and Wester, William. A Rich Tapestry: Supersymmetric Axions, Dark Radiation, and Inflationary Reheating. United States: N. p., 2014. Web. doi:10.1103/PhysRevD.90.115009.
Queiroz, Farinaldo S., Sinha, Kuver, & Wester, William. A Rich Tapestry: Supersymmetric Axions, Dark Radiation, and Inflationary Reheating. United States. doi:10.1103/PhysRevD.90.115009.
Queiroz, Farinaldo S., Sinha, Kuver, and Wester, William. Tue . "A Rich Tapestry: Supersymmetric Axions, Dark Radiation, and Inflationary Reheating". United States. doi:10.1103/PhysRevD.90.115009. https://www.osti.gov/servlets/purl/1156537.
@article{osti_1156537,
title = {A Rich Tapestry: Supersymmetric Axions, Dark Radiation, and Inflationary Reheating},
author = {Queiroz, Farinaldo S. and Sinha, Kuver and Wester, William},
abstractNote = {},
doi = {10.1103/PhysRevD.90.115009},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jul 15 00:00:00 EDT 2014},
month = {Tue Jul 15 00:00:00 EDT 2014}
}
  • Cited by 11
  • Recent studies of the cosmic microwave background, large scale structure, and big bang nucleosynthesis (BBN) show trends towards extra radiation. Within the framework of supersymmetric hadronic axion models, we explore two high-reheating-temperature scenarios that can explain consistently extra radiation and cold dark matter (CDM), with the latter residing either in gravitinos or in axions. In the gravitino CDM case, axions from decays of thermal saxions provide extra radiation already prior to BBN and decays of axinos with a cosmologically required TeV-scale mass can produce extra entropy. In the axion CDM case, cosmological constraints are respected with light eV-scale axinos andmore » weak-scale gravitinos that decay into axions and axinos. These decays lead to late extra radiation which can coexist with the early contributions from saxion decays. Recent results of the Planck satellite probe extra radiation at late times and thereby both scenarios. Further tests are the searches for axions at ADMX and for supersymmetric particles at the LHC.« less
  • We calculate the rate for thermal production of axions and saxions via scattering of quarks, gluons, squarks, and gluinos in the primordial supersymmetric plasma. Systematic field theoretical methods such as hard thermal loop resummation are applied to obtain a finite result in a gauge-invariant way that is consistent to leading order in the strong gauge coupling. We calculate the thermally produced yield and the decoupling temperature for both axions and saxions. For the generic case in which saxion decays into axions are possible, the emitted axions can constitute extra radiation already prior to big bang nucleosynthesis and well thereafter. Wemore » update associated limits imposed by recent studies of the primordial helium-4 abundance and by precision cosmology of the cosmic microwave background and large scale structure. We show that the trend towards extra radiation seen in those studies can be explained by late decays of thermal saxions into axions and that upcoming Planck results will probe supersymmetric axion models with unprecedented sensitivity.« less
  • We show that the modulated reheating mechanism can naturally account for dark radiation, whose existence is hinted by recent observations of the cosmic microwave background radiation and the primordial Helium abundance. In this mechanism, the inflaton decay rate depends on a light modulus which acquires almost scale-invariant quantum fluctuations during inflation. We find that the light modulus is generically produced by the inflaton decay and therefore a prime candidate for the dark radiation. Interestingly, an almost scale-invariant power spectrum predicted in the modulated reheating mechanism gives a better fit to the observation in the presence of the extra radiation. Wemore » discuss the production mechanism of the light modulus in detail taking account of its associated isocurvature fluctuations. We also consider a case where the modulus becomes the dominant component of dark matter.« less
  • In this paper a possible reheating mechanism in inflationary universe models is studied in some detail. Results are presented of numerical investigations of particle creation and corresponding reheating within a self-coupled scalar field model. By using the method of Hamiltonian diagonalization attention is devoted to the time development of the process and its parameter dependence. The effect of particle production is found to depend strongly on the anharmonicity of the potential around its minimum and on the amplitude of the oscillations of the scalar background field.