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Structure and mass distribution of spiral galaxies at intermediate redshifts

Antti Tamm·Peeter Tenjes
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Abstract

Using the HST archive WFPC2 observations and rotation curves measeured by Vogt et al. (1996), we constructed self-consistent light and mass distribution models for three disk galaxies at redshifts z = 0.15, 0.90 and 0.99. The models consist of three components: the bulge, the disk and the dark matter. Spatial density distribution parameters for the components were calculated. After applying k-corrections, mass-to-light ratios for galactic disks within the maximum disk assumption are M/L_B = 4.4, 1.2 and 1.2, respectively. Corresponding central densities of dark matter halos within a truncated isothermal model are 0.0092, 0.028 and 0.015 in units M_sol/pc^3. The light distribution of galaxies in outer parts is steeper than a simple exponential disk.

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Antti Tamm, Peeter Tenjes. 2002-12-23. Structure and mass distribution of spiral galaxies at intermediate redshifts. https://doi.org/10.1051/0004-6361%3A20030327

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