International E-publication: Publish Projects, Dissertation, Theses, Books, Souvenir, Conference Proceeding with ISBN.  International E-Bulletin: Information/News regarding: Academics and Research

Disks in Early-Type Galaxies from NIR observations

Author Affiliations

  • 1Department of Physics, University of Calicut, Malappuram, Kerala, INDIA

Res. J. Recent Sci., Volume 3, Issue (ISC-2013), Pages 420-422, (2014)


We report results from morphological analysis of 54 nearby (z < 0.018) early type galaxies, mainly from field, observed in near infra-red K band. Fitting their surface brightness profile with SÚrsic bulge and exponential disk, we find that majority of the sample galaxies, selected based on the detection of ionized gas, contains significant amounts of disk components. We find that 74% of our early-type galaxies are having a bulge to total luminosity ratio in K band. B/T, less than 0.5 while only 26% of the early-type galaxies are actually bulge dominant. The average value of bulge to total luminosity ratio (B/T) is 0.425 ▒ 0.145. The scale length of disk correlates well with its central surface brightness. We also find that the nature of disks in early-type galaxies resembles that observed in field spirals, and actually is with much lesser scatter, suggesting a much more coherent scenario for formation of disks in different types of galaxies.


  1. Canalizo G. and Bennert N., Spectacular shells in the host galaxy of the QSO MC2 1635+11, ApJ., 669, 801-809 (2007) Sikkema G., Carter D. and Peletier R. F., et al., HST/ACS observations of shell galaxies: inner shells, shell colours and dust, AandA., 467, 1011-1024 (2007)
  2. Sikkema G., Carter D. and Peletier R. F., et al., HST/ACS observations of shell galaxies: inner shells, shell colours and dust, AandA., 467, 1011-1024 (2007)
  3. Michard R. and Prugniel P., Peculiarities and populations in elliptical galaxies, 1. An old question revisited, AandA., 423, 833-847 (2004)
  4. Alan Dressler., Galaxy morphology in Rich clusters:Implications for the Formation and evolution of galaxies, ApJ., 236, 351-365 (1980)
  5. Bernardi M., et al., Early-Type galaxies in the sloan digital sky survey. II. Correlations between observables, AJ., 125, 1849 (2003)
  6. F. R. Marleau and L. Simard., Quantitative Morphology of Galaxies In the Hubble Deep Fild, ApJ., 507, 585-600 (1998)
  7. R. E. de Souza, D. A. Gadotti and S. Dos Anjos., BUDDA: A New Two- Dimensional bulge/Disk Decomposition code for Detailed Structural Analysis of Galaxies, ApJS., 153, 411-427 (2004)
  8. E. Pignatelli, G. Fasano and P. Cassata., GASPHOT: a tool for Galaxy Automatic Surface PHOTometry, AandA., 446, 373-388 (2006)
  9. J. Mendez-Abreu, J. A. L. Aguerri, E. M. Corsini, and E. Simonneau., Strucural properties of disk galaxies I. The intrinsic equatorial ellipticity of bulges, AandA.,478, 353-369 (2008), 420-422 (2014)
  10. Ravi Kumar C.D. et al., Photometric scaling relations for bulges of galaxies, A and A., 446, 827-838 (2006)
  11. Annibali F. et al., Nearby early-type galaxies with ionized gas. IV. Origin and powering mechanism of the ionized gas, A and A., 519, A40 (2010)
  12. Jedrzejewski R. and Schechter P.L., Minor-axis rotation in elliptical galaxies, AJ., 98, 147-165 (1989)
  13. Peng C.Y et al. Detailed structural decomposition of galaxy images, ApJ., 124, 266-293 (2002)
  14. J. L. SÚrsic., Atlas de Galaxies Australes, Cordoba, Observatorio, Astronomica (1968)
  15. K.C. Freeman., On the disks of Spiral and S0 galaxies, ApJ., 160, 811- 830 (1970)
  16. Dimitri A. Gadotti., Structural properties of pseudo-bulges, classical bulges and elliptical galaxies: a Sloan Digital Sky Survey perspective, MNRAS., 393, 1531-1552 (2009)
  17. C. Mollenhoff and J. Heidt., Surface photometry of spiral galaxies in NIR: Structural parameters of disks and bulges, A and A., 368, 16-37 (2001)
  18. . E. Laurikainen et al., Photometric scaling relations of lenticular and spiral galaxies, MNRAS., 405,1089-1118(2010)