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arXiv · astro-ph/9912319

A new measure of $σ_8$ using the lensing dispersion in high-$z$ type Ia SNe

Takashi Hamana·Toshifumi Futamase
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Abstract

The gravitational lensing magnification or demagnification due to large-scale structures induces a scatter in peak magnitudes of high redshift type Ia supernovae (SNe Ia). The amplitude of the lensing dispersion strongly depends on that of density fluctuations characterized by the $σ_8$ parameter. Therefore the value of $σ_8$ is constrained by measuring the dispersion in the peak magnitudes. We examine how well SN Ia data will provide a constraint on the value of $σ_8$ using a likelihood analysis method. It is found that the number and quality of SN Ia data needed for placing a useful constraint on $σ_8$ is attainable with Next Generation Space Telescope.

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Takashi Hamana, Toshifumi Futamase. 1999-12-15. A new measure of $σ_8$ using the lensing dispersion in high-$z$ type Ia SNe. https://doi.org/10.1086/308758

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