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Title: Dilaton-axion inflation with PBHs and GWs
Abstract We discuss two-stage dilaton-axion inflation models [1] and describe α -attractor models with either exponential or polynomial approach to the plateau.We implement one of the models of primordial black hole production proposed in [2] in the α -attractor context, and develop its supergravity version. The predictions of this model following from its polynomial attractor properties are: n s and r are α -independent, r depends on the mass parameter μ defining the approach to the plateau. The tachyonic instability at the transition point between the two stages of inflation is proportional to the negative curvature of the hyperbolic space ℛ K = -2/3 α . Thereforethe masses of primordial black holes (PBHs) and the frequencies of small-scale gravitational waves (GWs) in this model show significant dependence on  α .  more » « less
Award ID(s):
2014215
NSF-PAR ID:
10352512
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Journal of Cosmology and Astroparticle Physics
Volume:
2022
Issue:
08
ISSN:
1475-7516
Page Range / eLocation ID:
037
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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