English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Matching the number counts of high-$z$ sub-millimetre-selected galaxies(SMGs) has been a long standing problem for galaxy formation models. In thispaper, we use 3D dust radiative transfer to model the sub-mm emission fromgalaxies in the SIMBA cosmological hydrodynamic simulations, and comparepredictions to the latest single-dish observational constraints on theabundance of 850$\mathrm{\mu m}$-selected sources. We find good agreement withthe shape of the integrated 850$\mathrm{\mu m}$ luminosity function, and thenormalisation is within 0.25 dex at $> 3 \; \mathrm{mJy}$, unprecedented for afully cosmological hydrodynamic simulation, along with good agreement in theredshift distribution of bright SMGs. The agreement is driven primarily bySIMBA's good match to infrared measures of the star formation rate (SFR)function between $z = 2-4$ at high SFRs. Also important is the self-consistenton-the-fly dust model in SIMBA, which predicts, on average, higher dust masses(by up to a factor of 2.5) compared to using a fixed dust-to-metals ratio of0.3. We construct a lightcone to investigate the effect of far-field blending,and find that 52% of sources are blends of multiple components, which makes asmall contribution to the normalisation of the bright-end of the number counts.We provide new fits to the 850$\mathrm{\mu m}$ luminosity as a function of SFRand dust mass. Our results demonstrate that exotic solutions to the discrepancybetween sub-mm counts in simulations and observations, such as a top-heavy IMF,are unnecessary, and that sub-millimetre-bright phases are a naturalconsequence of massive galaxy evolution.

Reproducing sub-millimetre galaxy number counts with cosmological hydrodynamic simulations