In the simplest picture, the masses of string axions populating the axiverse depend on two parameters: the supersymmetry-breaking scale M-susy and the action S of the string instantons responsible for breaking the axion shift symmetry. In this work, we explore whether cosmological data can be used to probe these two parameters. Adopting string-inspired flat priors on log(10) M-susy and S and imposing that M-susy be sub-Planckian, we find S = 198 +/- 28. These bounds suggest that cosmological data complemented with string-inspired priors select a quite narrow axion mass range within the axiverse, log(10)(m(a)/eV) = -21.5(-2.3)(+1.3). We find that M-susy remains unconstrained due to a fundamental parameter degeneracy with S. We explore the significant impact of other choices of priors on the results, and we comment on similar findings in recent previous literature.

Cosmological window onto the string axiverse and the supersymmetry breaking scale / Visinelli, Luca; Vagnozzi, Sunny. - In: PHYSICAL REVIEW D. - ISSN 2470-0010. - 99:6(2019), p. 063517. [10.1103/physrevd.99.063517]

Cosmological window onto the string axiverse and the supersymmetry breaking scale

Sunny Vagnozzi
2019-01-01

Abstract

In the simplest picture, the masses of string axions populating the axiverse depend on two parameters: the supersymmetry-breaking scale M-susy and the action S of the string instantons responsible for breaking the axion shift symmetry. In this work, we explore whether cosmological data can be used to probe these two parameters. Adopting string-inspired flat priors on log(10) M-susy and S and imposing that M-susy be sub-Planckian, we find S = 198 +/- 28. These bounds suggest that cosmological data complemented with string-inspired priors select a quite narrow axion mass range within the axiverse, log(10)(m(a)/eV) = -21.5(-2.3)(+1.3). We find that M-susy remains unconstrained due to a fundamental parameter degeneracy with S. We explore the significant impact of other choices of priors on the results, and we comment on similar findings in recent previous literature.
2019
6
Visinelli, Luca; Vagnozzi, Sunny
Cosmological window onto the string axiverse and the supersymmetry breaking scale / Visinelli, Luca; Vagnozzi, Sunny. - In: PHYSICAL REVIEW D. - ISSN 2470-0010. - 99:6(2019), p. 063517. [10.1103/physrevd.99.063517]
File in questo prodotto:
File Dimensione Formato  
PhysRevD.99.063517.pdf

accesso aperto

Tipologia: Versione editoriale (Publisher’s layout)
Licenza: Creative commons
Dimensione 627.51 kB
Formato Adobe PDF
627.51 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11572/360126
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 79
  • ???jsp.display-item.citation.isi??? 79
social impact