Limiting the dimming of distant type Ia supernovae
نویسندگان
چکیده
منابع مشابه
Constraints on Cardassian Expansion from Distant type Ia Supernovae
The distant type Ia supernovae data compiled by Perlmutter et al. (1999) are used to analyze the Cardassian expansion scenario, which was recently proposed by Freese and Lewis (2002) as an alternative to a cosmological constant (or more generally a dark energy component) in explaining the currently accelerating universe. We show that the allowed intervals for n and zeq, the two parameters of th...
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Type Ia Supernovae are in many aspects still enigmatic objects. Their observational and theoretical exploration is in full swing, but we still have plenty to learn about these explosions. Recent years have already witnessed a bonanza of supernova observations. The increased samples from dedicated searches have allowed the statistical investigation of Type Ia Supernovae as a class. The observati...
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An explanation is given of the low value of Rλ ≡ Aλ/E(B − V ), the ratio of absolute to selective extinction deduced from Type Ia supernova observations. The idea involves scattering by dust clouds located in the circumstellar environment, or at the highest velocity shells of the supernova ejecta. The scattered light tends to reduce the effective Rλ in the optical, but has an opposite effect in...
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Since 1998 (Riess et al. 1, Perlmutter et al. 2), surveys of cosmologically distant Type Ia supernovae (SNe Ia) have indicated an acceleration of the expansion of the Universe, distant SNe Ia being dimmer that expected in a decelerating Universe. With the assumption that the Universe can be described on average as isotropic and homogeneous, this acceleration implies either the existence of a fl...
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ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2005
ISSN: 1475-7516
DOI: 10.1088/1475-7516/2005/02/005