Negative spectral index of f{sub NL} in the axion-type curvaton model

Journal Article · Mon Nov 01 04:00:00 EDT 2010 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2010/11/026· OSTI ID:22275385

Huang, Qing-Guo ^[1]

---

1. Kavli Institute for Theoretical Physics China (KITPC), Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China)

We derive the spectral index of f{sub NL} and its running from isocurvature single field and investigate the curvaton models with a negative spectral index of f{sub NL} in detail. In particular, a numerical study of the axion-type curvaton model is illustrated, and we find that the spectral index of f{sub NL} is negative and its absolute value is maximized around σ{sub *} = πf/2 for the potential V(σ) = m{sup 2}f{sup 2}(1−cos (σ/f)). The spectral index of f{sub NL} can be O(−0.1) for the axion-type curvaton model. A convincing detection of a positive n{sub f{sub N{sub L}}} will rule out the axion-type curvaton model. In addition, we also give a general discussion about the detectable parameter space for the curvaton model with a polynomial potential.

• OSTI ID: 22275385
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 11 Vol. 2010; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AXIONS
COSMOLOGICAL MODELS
COSMOLOGY
INDEXES
NUMERICAL ANALYSIS
POLYNOMIALS
POTENTIALS