University of Sussex
Browse
PhysRevLett.105.181302.pdf (185.06 kB)

Non-Gaussianity in Axion N-flation Models

Download (185.06 kB)
journal contribution
posted on 2023-06-07, 20:02 authored by Soo A Kim, Andrew R Liddle, David SeeryDavid Seery
We study perturbations in the multifield axion N-flation model, taking account of the full cosine potential. We find significant differences from previous analyses which made a quadratic approximation to the potential. The tensor-to-scalar ratio and the scalar spectral index move to lower values, which nevertheless provide an acceptable fit to observation. Most significantly, we find that the bispectrum non-Gaussianity parameter fNL may be large, typically of order 10 for moderate values of the axion decay constant, increasing to of order 100 for decay constants slightly smaller than the Planck scale. Such a non-Gaussian fraction is detectable. We argue that this property is generic in multifield models of hilltop inflation.

History

Publication status

  • Published

File Version

  • Published version

Journal

Physical Review Letters

ISSN

1050-2947

Issue

18

Volume

105

Pages

4.0

Department affiliated with

  • Physics and Astronomy Publications

Full text available

  • Yes

Peer reviewed?

  • Yes

Legacy Posted Date

2012-02-06

First Open Access (FOA) Date

2016-03-22

First Compliant Deposit (FCD) Date

2016-11-10

Usage metrics

    University of Sussex (Publications)

    Categories

    No categories selected

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC