A detection of CO(1-0) emission from the Cloverleaf, using the ultra-wide-bandwidth Zpectrometer at the NRAO Green Bank Telescope. See here for further details.
From Cresci et al. (2006, A&A, 458, 385): number counts vs. K-band magnitude for morphologically selected early-type (left) and late-type (right) galaxies in the Survey of a Wide Area with NACO (SWAN). Solid symbols are based on VLT adaptive optics imaging data in magnitude bins unaffected by field selection biases; curves represent the a priori predictions of passive luminosity evolution (PLE) and semi-analytic (SA) models.
From Rupke, Veilleux, & Baker (2008, ApJ, 674, 172): residuals relative to the local luminosity-metallicity (black) and mass-metallicity (red) relations vs. infrared luminosity. LIRGs and ULIRGs are underabundant relative to non-IR-luminous galaxies of similar K-band luminosity and mass; the greatest discrepancies are seen in the most IR-luminous systems. These trends are most naturally attributed to gas inflows: in increasingly violent mergers, metal-poor gas from the outskirts of progenitor galaxies has an increasingly dilutive effect on the oxygen abundance in the nucleus.