Observational constraints on silent quartessence

• Verfasst von: Amendola, Luca [VerfasserIn]
• Verfasst von: Waga, Ioav [VerfasserIn]
• Verfasst von: Finelli, Fabio [VerfasserIn]
• Titel: Observational constraints on silent quartessence
• Verf.angabe: Luca Amendola, INAF/Osservatorio Astronomico di Roma, Via Frascati 33, I-00040 Monte Porzio Catone, RM, Italy ; Ioav Waga, Universidade Federal do Rio de Janeiro, Instituto de Física, CEP 21941-972, Rio de Janeiro, RJ, Brazil ; Fabio Finelli, INAF/IASF, Sezione di Bologna, Istituto di Astrofisica Spaziale e Fisica Cosmica, Istituto Nazionale di Astrofisica, via Gobetti, 101, I-40129 Bologna, Italy
• Fussnoten: Gesehen am 16.11.2017
• Titel Quelle: Enthalten in: De.arxiv.org
• Jahr Quelle: 2005
• Band/Heft Quelle: (2005) Artikel-Nummer 0509099, 7 Seiten
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1565416228

Abstract

We derive new constraints set by SNIa experiments (`gold' data sample of Riess et al.), X-ray galaxy cluster data (Allen et al. Chandra measurements of the X-ray gas mass fraction in 26 clusters), large scale structure (Sloan Digital Sky Survey spectrum) and cosmic microwave background (WMAP) on the quartessence Chaplygin model. We consider both adiabatic perturbations and intrinsic non-adiabatic perturbations such that the effective sound speed vanishes (Silent Chaplygin). We show that for the adiabatic case, only models with equation of state parameter $ |\alpha |\lesssim 10^{-2}$ are allowed: this means that the allowed models are very close to \LambdaCDM. In the Silent case, however, the results are consistent with observations in a much broader range, -0.3<\alpha<0.7.