A fundamental plane for field star-forming galaxies

Scritto in Pubblicazioni

Context. Star formation rate (SFR), metallicity, and stellar mass are
among the most important parameters of star-forming (SF) galaxies
characterizing their formation and evolution. They are known to be
related to each other both at low and high redshift in the
mass-metallicity, mass-SFR, and metallicity-SFR relations. <BR /> Aims:
We demonstrate the existence of a plane in a 3D parameter space defined
by the axes SFR [log (SFR)(M<SUB>ȯ</SUB> yr<SUP>-1</SUP>)] , gas
metallicity [12 + log (O/H)], and stellar mass…

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The Peculiar Optical Spectrum of 4C+22.25: Imprint of a Massive Black Hole Binary?

Scritto in Pubblicazioni

We report the discovery of peculiar features in the optical spectrum of
4C+22.25, a flat spectrum radio quasar at z = 0.4183 observed in the
Sloan Digital Sky Survey and in a dedicated spectroscopic follow-up from
the Nordic Optical Telescope. The Hβ and Hα lines show broad
profiles (FWHM ~ 12,000 km s<SUP>-1</SUP>), faint fluxes, and extreme
offsets (Δv = 8700 ± 1300 km s<SUP>-1</SUP>) with respect
to the narrow emission lines. These features show no significant
variation in a time lag of ~3.1 yr (rest frame). We rule out possible
interpretations based on the…

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2003 QZ30

Scritto in Pubblicazioni

Available from the Minor Planet Center.
Available from the Minor Planet Center.