Open AccessThe role of star formation in the Tully–Fisher law
Author(s) -
Heavens A. F.,
Jimenez R.
Publication year - 1999
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.1999.02448.x
Subject(s) - physics , astrophysics , redshift , star formation , galaxy , halo , cosmology , globular cluster , power law , cosmological constant , universe , stars , astronomy , theoretical physics , statistics , mathematics
We investigate the influence of the star formation rate on the Tully–Fisher relation. We find that a simple model which combines the empirically determined star formation rate with the expected properties of galaxy haloes provides a remarkably good fit to the absolute magnitude–rotation speed correlation. We find that the power‐law nature, and its slope, normalization and scatter are all readily accounted for if the Universe has a low density parameter, with or without a cosmological constant, and discs are assembled at z ∼ 1–1.5. Moreover, this agreement is found simultaneously in four wavebands. An Einstein–de Sitter universe produces discs that are too faint unless the discs are assembled at z ∼ 0.5. The scatter in the relation is due to a combination of the expected range of spin parameters of the haloes and the range of formation redshifts. The source of the scatter opens up possibilities of a better galactic distance indicator, if spectroscopic observations of globular clusters can be used to determine the halo rotation.