Axion cosmology, lattice QCD and the dilute instanton gas

Borsanyi, S. ; Dierigl, M. ; Fodor, Z. ; Katz, S.D. ; Mages, S.W. ; Nogradi, D. ; Redondo, J. (Universidad de Zaragoza) ; Ringwald, A. ; Szabo, K.K.

Resumen: Axions are one of the most attractive dark matter candidates. The evolution of their number density in the early universe can be determined by calculating the topological susceptibility ¿(T) of QCD as a function of the temperature. Lattice QCD provides an ab initio technique to carry out such a calculation. A full result needs two ingredients: physical quark masses and a controlled continuum extrapolation from non-vanishing to zero lattice spacings. We determine ¿(T) in the quenched framework (infinitely large quark masses) and extrapolate its values to the continuum limit. The results are compared with the prediction of the dilute instanton gas approximation (DIGA). A nice agreement is found for the temperature dependence, whereas the overall normalization of the DIGA result still differs from the non-perturbative continuum extrapolated lattice results by a factor of order ten. We discuss the consequences of our findings for the prediction of the amount of axion dark matter.

Idioma: Inglés

DOI: 10.1016/j.physletb.2015.11.020

Año: 2016

Publicado en: PHYSICS LETTERS B 752 (2016), 175-181
ISSN: 0370-2693

Factor impacto JCR: 4.807 (2016)

Categ. JCR: ASTRONOMY & ASTROPHYSICS rank: 12 / 63 = 0.19 (2016) - Q1 - T1
Categ. JCR: PHYSICS, PARTICLES & FIELDS rank: 6 / 29 = 0.207 (2016) - Q1 - T1
Categ. JCR: PHYSICS, NUCLEAR rank: 3 / 20 = 0.15 (2016) - Q1 - T1

Factor impacto SCIMAGO: 3.032 - Nuclear and High Energy Physics (Q1)

Financiación: info:eu-repo/grantAgreement/ES/MINECO/RYC-2012-10597

Tipo y forma: Article (Published version)

Área (Departamento): Área Física Teórica (Dpto. Física Teórica)