Does Environment Affect the Star Formation Histories of Early-Type Galaxies?

  title={Does Environment Affect the Star Formation Histories of Early-Type Galaxies?},
  author={Ignacio Ferreras and Anna Pasquali and Ben Rogers and MSSLUcl and ARIHeidelberg and King's College London},
  journal={arXiv: Cosmology and Nongalactic Astrophysics},
Differences in the stellar populations of galaxies can be used to quantify the effect of environment on the star formation history. We target a sample of early-type galaxies from the Sloan Digital Sky Survey in two different environmental regimes: close pairs and a general sample where environment is measured by the mass of their host dark matter halo. We apply a blind source separation technique based on principal component analysis, from which we define two parameters that correlate… Expand

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