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Title: Phenomenological aspects of no-scale inflation models

Abstract

We discuss phenomenological aspects of inflationary models wiith a no-scale supergravity Kähler potential motivated by compactified string models, in which the inflaton may be identified either as a Kähler modulus or an untwisted matter field, focusing on models that make predictions for the scalar spectral index n{sub s} and the tensor-to-scalar ratio r that are similar to the Starobinsky model. We discuss possible patterns of soft supersymmetry breaking, exhibiting examples of the pure no-scale type m{sub 0}=B{sub 0}=A{sub 0}=0, of the CMSSM type with universal A{sub 0} and m{sub 0}≠0 at a high scale, and of the mSUGRA type with A{sub 0}=B{sub 0}+m{sub 0} boundary conditions at the high input scale. These may be combined with a non-trivial gauge kinetic function that generates gaugino masses m{sub 1/2}≠0, or one may have a pure gravity mediation scenario where trilinear terms and gaugino masses are generated through anomalies. We also discuss inflaton decays and reheating, showing possible decay channels for the inflaton when it is either an untwisted matter field or a Kähler modulus. Reheating is very efficient if a matter field inflaton is directly coupled to MSSM fields, and both candidates lead to sufficient reheating in the presence of a non-trivialmore » gauge kinetic function.« less

Authors:
 [1];  [2];  [3];  [4];  [5];  [6];  [3]
  1. Theoretical Particle Physics and Cosmology Group, Department of Physics,King’s College London,WC2R 2LS London (United Kingdom)
  2. (Switzerland)
  3. William I. Fine Theoretical Physics Institute, School of Physics and Astronomy,University of Minnesota,116 Church Street SE, Minneapolis, MN 55455 (United States)
  4. George P. and Cynthia W. Mitchell Institute for Fundamental Physics andAstronomy, Texas A&M University,College Station, 77843 Texas (United States)
  5. (HARC), Mitchell Campus, Woodlands, 77381 Texas (United States)
  6. (Greece)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22458384
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 10; Other Information: PUBLISHER-ID: JCAP10(2015)003; OAI: oai:repo.scoap3.org:12066; Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COSMOLOGICAL INFLATION; GRAVITATION; MATTER; POTENTIALS; SCALAR FIELDS; STRING MODELS; SUPERGRAVITY; SUPERSYMMETRY; SYMMETRY BREAKING; TENSOR FIELDS

Citation Formats

Ellis, John, Theory Division, CERN,CH-1211 Geneva 23, Garcia, Marcos A.G., Nanopoulos, Dimitri V., Astroparticle Physics Group, Houston Advanced Research Center, Academy of Athens, Division of Natural Sciences, 28 Panepistimiou Avenue, 10679 Athens, and Olive, Keith A. Phenomenological aspects of no-scale inflation models. United States: N. p., 2015. Web. doi:10.1088/1475-7516/2015/10/003.
Ellis, John, Theory Division, CERN,CH-1211 Geneva 23, Garcia, Marcos A.G., Nanopoulos, Dimitri V., Astroparticle Physics Group, Houston Advanced Research Center, Academy of Athens, Division of Natural Sciences, 28 Panepistimiou Avenue, 10679 Athens, & Olive, Keith A. Phenomenological aspects of no-scale inflation models. United States. doi:10.1088/1475-7516/2015/10/003.
Ellis, John, Theory Division, CERN,CH-1211 Geneva 23, Garcia, Marcos A.G., Nanopoulos, Dimitri V., Astroparticle Physics Group, Houston Advanced Research Center, Academy of Athens, Division of Natural Sciences, 28 Panepistimiou Avenue, 10679 Athens, and Olive, Keith A. 2015. "Phenomenological aspects of no-scale inflation models". United States. doi:10.1088/1475-7516/2015/10/003.
@article{osti_22458384,
title = {Phenomenological aspects of no-scale inflation models},
author = {Ellis, John and Theory Division, CERN,CH-1211 Geneva 23 and Garcia, Marcos A.G. and Nanopoulos, Dimitri V. and Astroparticle Physics Group, Houston Advanced Research Center and Academy of Athens, Division of Natural Sciences, 28 Panepistimiou Avenue, 10679 Athens and Olive, Keith A.},
abstractNote = {We discuss phenomenological aspects of inflationary models wiith a no-scale supergravity Kähler potential motivated by compactified string models, in which the inflaton may be identified either as a Kähler modulus or an untwisted matter field, focusing on models that make predictions for the scalar spectral index n{sub s} and the tensor-to-scalar ratio r that are similar to the Starobinsky model. We discuss possible patterns of soft supersymmetry breaking, exhibiting examples of the pure no-scale type m{sub 0}=B{sub 0}=A{sub 0}=0, of the CMSSM type with universal A{sub 0} and m{sub 0}≠0 at a high scale, and of the mSUGRA type with A{sub 0}=B{sub 0}+m{sub 0} boundary conditions at the high input scale. These may be combined with a non-trivial gauge kinetic function that generates gaugino masses m{sub 1/2}≠0, or one may have a pure gravity mediation scenario where trilinear terms and gaugino masses are generated through anomalies. We also discuss inflaton decays and reheating, showing possible decay channels for the inflaton when it is either an untwisted matter field or a Kähler modulus. Reheating is very efficient if a matter field inflaton is directly coupled to MSSM fields, and both candidates lead to sufficient reheating in the presence of a non-trivial gauge kinetic function.},
doi = {10.1088/1475-7516/2015/10/003},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 10,
volume = 2015,
place = {United States},
year = 2015,
month =
}
  • We discuss phenomenological aspects of inflationary models wiith a no-scale supergravity Kähler potential motivated by compactified string models, in which the inflaton may be identified either as a Kähler modulus or an untwisted matter field, focusing on models that make predictions for the scalar spectral index n{sub s} and the tensor-to-scalar ratio r that are similar to the Starobinsky model. We discuss possible patterns of soft supersymmetry breaking, exhibiting examples of the pure no-scale type m{sub 0} = B{sub 0} = A{sub 0} = 0, of the CMSSM type with universal A{sub 0} and m{sub 0} ≠ 0 at a high scale, and of the mSUGRA type withmore » A{sub 0} = B{sub 0} + m{sub 0} boundary conditions at the high input scale. These may be combined with a non-trivial gauge kinetic function that generates gaugino masses m{sub 1/2} ≠ 0, or one may have a pure gravity mediation scenario where trilinear terms and gaugino masses are generated through anomalies. We also discuss inflaton decays and reheating, showing possible decay channels for the inflaton when it is either an untwisted matter field or a Kähler modulus. Reheating is very efficient if a matter field inflaton is directly coupled to MSSM fields, and both candidates lead to sufficient reheating in the presence of a non-trivial gauge kinetic function.« less
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