SIMBAD references

Context. Atomic fine structure lines have been detected in the local Universe and at high redshifts over the past decades. The [CII] emission line at 158 µm is an important observable as it provides constraints on the interstellar medium (ISM) cooling processes.
Aims. We develop a physically motivated framework to simulate the production of far-infrared line emission from galaxies in a cosmological context. This first paper sets out our methodology and describes its first application: simulating the [CII] 158 µm line emission in the local Universe.
Methods. We combine the output fromEAGLE cosmological hydrodynamical simulations with a multi-phase model of the ISM. Gas particles are divided into three phases: dense molecular gas, neutral atomic gas, and diffuse ionised gas (DIG). We estimate the [CII] line emission from the three phases using a set of CLOUDY cooling tables.
Results. Our results agree with previous findings regarding the contribution of these three ISM phases to the [CII] emission. Our model shows good agreement with the observed L_[CII-star formation rate (SFR) relation in the local Universe within 0.4 dex scatter.
Conclusions. The fractional contribution to the [CII] line from different ISM phases depends on the total SFR and metallicity. The neutral gas phase dominates the [CII] emission in galaxies with SFR∼0.01-1M_☉/yr, but the ionised phase dominates at lower SFRs. Galaxies above solar metallicity exhibit lower L_[CII/SFR ratios for the neutral phase. In comparison, the L_[CII/SFR ratio in the DIG is stable when metallicity varies. We suggest that the reduced size of the neutral clouds, caused by increased SFRs, is the likely cause for the L_[CII deficit at high infrared luminosities, althoughEAGLE simulations do not reach these luminosities at z=0.