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6 Summary and conclusions

We have carried out a morphological study of the UCM Survey galaxies based on Johnson B imaging. This paper, jointly with Paper I (Pérez-González et al. 2000), have analyzed the main features of the UCM sample concerning integrated and surface photometry in the B bandpass.

Paper I presented integrated apparent and absolute B luminosities as well as isophote 24 magarcsec-2 magnitudes. Effective radii and B-r colours were also calculated in this first release. In the present paper we have outlined the main results concerning bulge-disk decomposition values, ellipticities, position angles, concentration indices, mean photometric radii and surface brightnesses and asymmetry coefficients.


 

 
Table 6: Hubble types for the UCM galaxies
Filter S0 Sa Sb Sc+ Irr BCD Int Total
B 14 38 69 50 5 8 6 190
  7% 20% 36% 26% 3% 4% 3%  
r 12 41 43 46 5 8 - 155
  7% 27% 28% 30% 3% 5%    


Number of galaxies and percentage of the UCM galaxies according to their Hubble type in the Johnson B and the Gunn r bandpasses.



 

 
Table 7: Averaged values of each Hubble type
Parameter S0 Sa Sb Sc+ Irr BCD Int
B/T 0.53 0.39 0.16 0.04 0.07 0.41 0.30
$\mu_{\rm e}$ 20.6 20.7 21.3 21.5 21.8 21.5 20.1
c31 5.3 3.8 3.3 2.7 2.9 3.5 5.0
c42 4.3 3.5 3.2 2.7 2.8 3.4 4.0
$c_{\rm in}$ 0.58 0.50 0.40 0.29 0.33 0.35 0.57
A 0.09 0.10 0.10 0.11 0.21 0.06 0.20
(barred) 0.06 0.15 0.11 0.12 - - -



  \begin{figure}
\par\includegraphics[angle=-90,width=8.8cm,clip]{H2366f17.ps}\end{figure} Figure 17: Concentration index $c_{\rm in}$ versus asymmetry coefficient. Different symbols stand for distinct morphological types. Ellipses show the median and standard deviation of each parameter for the different morphological types


  \begin{figure}
\par\includegraphics[angle=-90,width=8.8cm,clip]{H2366f18.ps}\end{figure} Figure 18: Mean effective surface brightness versus absolute magnitude. Ellipses show the median and standard deviation of each parameter for the different morphological types

All the above information has been used to perform the morphological classification of the UCM galaxies. The sample is dominated by late Hubble type objects (65% being Sb or later). We have not found a great difference between this classification and the results achieved with the Gunn r data (Vitores et al. 1996a, 1996b). Our galaxies are characterized by shorter disks than those of normal spirals. Besides, they seem to be objects with a high luminosity concentration. A preliminary comparison between the characteristics of the sample in the red and blue bandpasses, yields to the result that emission-line galaxies have a higher concentration of blue light than red light in the inner parts of the objects; on the contrary, they also seem to be more extended in B than in r.

Finally, a size-luminosity correlation has been outlined. We have also presented several plots where a morphological segregation is patent. These plots involve information about luminosity, concentration of light and asymmetry.

In next papers we will face a most exhaustive comparison between bands, including colour gradients and a stellar population study. Likewise, we will likened our sample to high-redshifts surveys searching for clues to their nature and galaxy evolution.

Acknowledgements
This paper is based on observations obtained at the German-Spanish Astronomical Centre, Calar Alto, Spain, operated by the Max-Planck Institute für Astronomie (MPIE), Heidelberg, jointly with the Spanish Commission for Astronomy. It is also partly based on observations made with the Jacobus Kapteyn Telescope operated on the island of La Palma by the Royal Greenwich Observatory in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias and the 1.52 m telescope of the EOCA/OAN Observatory. This research has made use of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. We have also use of the LEDA database, http://www-obs.univ-lyon1.fr. This research was also supported by the Spanish Programa Sectorial de Promoción General del Conocimiento under grants PB96-0610 and PB96-0645. P. G. Pérez-González acknowledges the receipt of a "Formación de Profesorado Universitario'' fellowship from the Spanish "Ministerio de Educación y Cultura''.

We would like to thank C. E. García-Dabó and S. Pascual for their help during part of the observing runs and stimulating conversations. We thank M. N. Estévez for carefully reading the manuscript and making some useful remarks. We are also grateful to Dr. E. Emsellem for his helpful comments and suggestions.


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