Generating the cosmic microwave background power asymmetry with
Physical Review D
MetadataShow full item record
We consider a higher order term in the δN expansion for the CMB power asymmetry generated by a superhorizon isocurvature field fluctuation. The term can generate the asymmetry without requiring a large value of fNL. Instead it produces a non-zero value of gNL. A combination of constraints leads to an allowed region in fNL − gNL space. To produce the asymmetry with this term without a large value of fNL we find that the isocurvature field needs to contribute less than the inflaton towards the power spectrum of the curvature perturbation.
AuthorsKenton, Z; Mulryne, DJ; Thomas, S
- College Publications