... z $\approx$ 2-3

Based on observations taken with the Ultraviolet and Visual Echelle Spectrograph (UVES) on the Very Large Telescope (VLT) Unit 2 (Kueyen) at Paranal, Chile, operated by ESO.

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...

Figure 1 is only available in electronic form at http://www.aanda.org

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...

Table 1 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.728.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/473/791

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... ratio

C II^* is an excited electronic state of singly ionized carbon. The transition at 158 $\mu$m resulting from the decay from fine-structure state $^2\rm P_{3/2}$ to $^2\rm P_{1/2}$ in the 2s²2p term of C⁺ is the principal coolant for diffuse neutral interstellar gas.

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... mechanism

Cool but highly ionized clouds could however be produced by a non-equilibrium collisional ionization scenario, in which initially hot gas has cooled faster than it has recombined, leading to "frozen-in'' ionization (Kafatos 1973).

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...Brooks et al. 2007)

Low star formation efficiency at low galactic masses may also contribute to the mass-metallicity relationship (Brooks et al. 2007; Finlator & Davé 2007).

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...-1

This relation assumes each supernova releases 10⁵¹ erg of kinetic energy and that one supernova follows from every 125 $M_\odot$ of star formation.

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