Pseudobulges in the Disk Galaxies NGC 7690 and NGC 4593

  title={Pseudobulges in the Disk Galaxies NGC 7690 and NGC 4593},
  author={John Kormendy and Mark Edward Cornell and David L. Block and Johan H. Knapen and Emma L. Allard},
  journal={The Astrophysical Journal},
We present Ks-band surface photometry of NGC 7690 (Hubble type Sab) and NGC 4593 (SBb). We find that, in both galaxies, a major part of the bulge is as flat as the disk and has approximately the same color as the inner disk. In other words, the bulges of these galaxies have disklike properties. We conclude that these are examples of pseudobulges, that is, products of secular dynamical evolution. Nonaxisymmetries such as bars and oval disks transport disk gas toward the center. There star… 

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