Simplified quartessence cosmology

Autor(es)

Lima, J. A. S. ^[1] ; Cunha, J. V. ^[1] ; Alcaniz, J. S. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508900 Sao Paulo - Brazil

^[2] Observ Nacl, Dept Astron, BR-20921400 Rio De Janeiro - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Astroparticle Physics; v. 31, n. 3, p. 233-236, APR 2009.
• Citações Web of Science: 8

Resumo

We propose a new class of accelerating world models unifying the cosmological dark sector (dark matter and dark energy). All the models are described by a simplified version of the Chaplygin gas quartessence cosmology. It is found that even for Omega(k) not equal 0, this quartessence scenario depends only on a pair of parameters which can severely be constrained by the cosmological tests. As an example we perform a joint analysis involving the latest SNe type la data and the recent Sloan Digital Sky Survey measurement of baryon acoustic oscillations. In our analysis we have considered the SNe type la Union sample compiled by Kowalski et al. {[}M. Kowalski et al., Astrophys. J. 686 (2008) 749, arXiv:0804.4142]. At 95.4% (c.l.), we find for BAD + Union sample, alpha = 0.81(-0.04)(+0.04) and Omega(Q4) = 1.15(-0.17)(+0.16) The best-fit for this simplified quartessence scenario is a spatially closed Universe and its reduced chi(2) is exactly the same of the flat concordance model (Lambda CDM). (C) 2009 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 05/02809-5 - Investigando as componentes escuras do universo com raios-X, SNE IA, RCF, efeito Sunyaev-Zel'dovich e idades de objetos velhos
• Beneficiário: João Vital da Cunha Júnior
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 04/13668-0 - Cosmologia na era da precisão: energia escura, matéria escura e radiação cósmica de fundo
• Beneficiário: Jose Ademir Sales de Lima
• Modalidade de apoio: Auxílio à Pesquisa - Temático