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Дата изменения: Mon Dec 23 18:23:59 2013
Дата индексирования: Fri Feb 28 17:11:57 2014
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Поисковые слова: herbig-haro object

Documentation: LEDA: parameter: mod0

Distance modulus: mod0

The distance modulus, mod0 [mag] is either computed from the distance catalogue or using the Tully-Fisher or Faber-Jackson relations.

When measurements are available in the distance catalogue, mod0 is computed as the weighted average of those measurements. Otherwise, it is determined either using the Tully-Fisher or Faber-Jackson relation for respectively spiral or elliptical galaxies.

The Tully-Fisher relation uses the corrected total magnitude btc and the maximum velocity of rotation vmaxg.
mod0 = btc + 6.5 log(vmaxg) + 6.3

The Faber-Jackson relation uses the corrected total magnitude btc and the central velocity dispersion vdis.
mod0 = btc + 6.2 vdis + 5.9

Another parameter, modz (redshift distance modulus), estimates the luminosity-distance using the redshift.

HyperLeda

Questions: leda@univ-lyon1.fr