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Journal of High Energy Physics

, 2012:146 | Cite as

The type IIB string axiverse and its low-energy phenomenology

  • Michele Cicoli
  • Mark D. GoodsellEmail author
  • Andreas Ringwald
Open Access
Article

Abstract

We study closed string axions in type IIB orientifold compactifications. We show that for natural values of the background fluxes the moduli stabilisation mechanism of the LARGE Volume Scenario (LVS) gives rise to an axiverse characterised by the presence of a QCD axion plus many light axion-like particles whose masses are logarithmically hierarchical. We study the phenomenological features of the LVS axiverse, deriving the masses of the axions and their couplings to matter and gauge fields. We also determine when closed string axions can solve the strong CP problem, and analyse the first explicit examples of semi-realistic models with stable moduli and a QCD axion candidate which is not eaten by an anomalous Abelian gauge boson. We discuss the impact of the choice of inflationary scenario on the LVS axiverse, and summarise the astrophysical, cosmological and experimental constraints upon it. Moreover, we show how models can be constructed with additional light axion-like particles that could explain some intriguing astrophysical anomalies, and could be searched for in the next generation of axion helioscopes and light-shining-through-a-wall experiments.

Keywords

Strings and branes phenomenology 

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Copyright information

© SISSA 2012

Authors and Affiliations

  • Michele Cicoli
    • 1
    • 2
  • Mark D. Goodsell
    • 3
    Email author
  • Andreas Ringwald
    • 4
  1. 1.Abdus Salam ICTPTriesteItaly
  2. 2.INFN — Sezione di TriesteTriesteItaly
  3. 3.CERN, Theory DivisionGeneva 23Switzerland
  4. 4.Deutsches Elektronen-Synchrotron, DESYHamburgGermany

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