Colour distributions in E-S0 galaxies --- VI. A discussion of colour gradients in ellipticals

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

25

Galaxies: Elliptical And Lenticular, Cd, Galaxies: Fundamental Parameters

Scientific paper

The data from the surveys by Franx et al. (1989), Peletier et al. (1990), Goudfrooij et al. (1994a), completed by our own measurements, have been used to build a sample of ellipticals with the full array of U-B, B-V, B-R and V-I colours, and corresponding gradients. A number of objects with data for only 3 colours are also considered. Photometric profiles were re-calibrated in a coherent colours system, and a seemingly successful attempt was made to improve gradients by minor corrections to adopted sky background values. "External" probable errors are obtained for the revised data by comparisons between the various sources. These have poor statistical weight in U-B and V-I. An ad hoc "standard" gradient Δs is defined as a weighted average of the four gradients in the above listed colours (or only three). The correlations of the various gradients to Δs are considered, and their slopes ΔU-B/Δs,... are compared to the corresponding calculated ratios for current hypothesis regarding the origin of colour gradients in ellipticals, i.e. population gradients and large scale dust distributions. Both the ratios for the U-B and V-I colours are not compatible with the explanation in terms of diffuse dust but tend to agree with the explanation in terms of metallicity variations. The correlation between the gradient ΔU-B and the standard one Δs might be worse than could be explained by observational errors. Both population variations and possibly complex dust dustributions should be invoked to explain the complications of colour gradients. Based in part on observations collected at the Observatoire de Haute-Provence and from the Centre de Données Stellaires, Strasbourg

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Colour distributions in E-S0 galaxies --- VI. A discussion of colour gradients in ellipticals does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Colour distributions in E-S0 galaxies --- VI. A discussion of colour gradients in ellipticals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Colour distributions in E-S0 galaxies --- VI. A discussion of colour gradients in ellipticals will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-734182

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.