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Date and Time of the Query: 2019-04-20 T18:06:41 PDT
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For refcode 2002MNRAS.334..721G:
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NED Abstract

Copyright by Royal Astronomical Society. 2002MNRAS.334..721G Mass-to-light ratios from the fundamental plane of spiral galaxy discs Alister W. Graham ABSTRACT The best-fitting two-dimensional plane within the three-dimensional space of spiral galaxy disc observables (rotational velocity v_rot_, central disc surface brightness {mu}_0_ = -2.5 log I_0_ and disc scalelength h) has been constructed. Applying the three-dimensional bisector method of regression analysis to a sample of ~100 spiral galaxy discs that span more than 4 mag arcsec^-2^ in central disc surface brightness yields v_rot_ is proportional to I_0_^0.50+/-0.05^ h^0.77+/-0.07^ (B band) and v_rot_ is proportional to I_0_^0.43+/-0.04^ h^0.69+/-0.07^ (R band). Contrary to popular belief, these results suggest that in the B band, the dynamical mass-to-light ratio (within four disc scalelengths) is largely independent of the surface brightness, varying as I_0_^0.00+/-0.10 h^0.54+/-0.14^. Consistent results were obtained when the range of the analysis was truncated by excluding the low-surface-brightness galaxies. Previous claims that M/L_B_ varies with I_0,B_^-1/2^ are shown to be misleading and/or caused by galaxy selection effects - not all low-surface-brightness disc galaxies are dark matter dominated. The situation is, however, different in the near-infrared where L_K'_ is proportional to v^4^ and M/L_K'_ is shown to vary as I_0,K'_^-1/2^. Theoretical studies of spiral galaxy discs should therefore not assume a constant M/L ratio within any given passband. The B-band dynamical mass-to-light ratio (within four disc scalelengths) has no obvious correlation with (B - R) disc colour, while in the K' band it varies as -1.25 +/- 0.28(B - R). Combining the present observational data with recent galaxy model predictions implies that the logarithm of the stellar-to-dynamical mass ratio is not a constant value, but increases as discs become redder, varying as 1.70 +/- 0.28(B - R). Keywords: galaxies: fundamental parameters - galaxies: kinematics and dynamics - galaxies: photometry - galaxies: spiral - dark matter.
Retrieve 99 NED objects in this reference.
Please click here for ADS abstract

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