University of Sussex
Browse
10_1051_0004-6361_201322217.pdf (3.03 MB)

The evolution of the dust temperatures of galaxies in the SFR–M*plane up to z ~ 2

Download (3.03 MB)
journal contribution
posted on 2023-06-08, 21:02 authored by B Magnelli, D Lutz, A Saintonge, S Berta, P Santini, M Symeonidis, B Altieri, P Andreani, H Aussel, M Béthermin, J Bock, A Bongiovanni, J Cepa, A Cimatti, A Conley, E Daddi, D Elbaz, N M Förster Schreiber, R Genzel, R J Ivison, E Le Floc’h, G Magdis, R Maiolino, R Nordon, Seb OliverSeb Oliver, M Paget, A Pérez García, A Poglitsch, P Popesso, F Pozzi, L Riguccini, G Rodighiero, D Rosario, I Roseboom, M Sanchez-Portal, D Scott, E Sturm, L J Tacconi, I Valtchanov, L Wang, S Wuyts
We study the evolution of the dust temperature of galaxies in the SFR-M * plane up to z ~ 2 using far-infrared and submillimetre observations from the Herschel Space Observatory taken as part of the PACS Evolutionary Probe (PEP) and Herschel Multi-tiered Extragalactic Survey (HerMES) guaranteed time key programmes. Starting from a sample of galaxies with reliable star-formation rates (SFRs), stellar masses (M * ) and redshift estimates, we grid the SFR-M * parameter space in several redshift ranges and estimate the mean dust temperature (T dust ) of each SFR–M * -z bin. Dust temperatures are inferred using the stacked far-infrared flux densities (100–500µm) of our SFR–M * -z bins. At all redshifts, the dust temperature of galaxies smoothly increases with rest-frame infrared luminosities (L IR ), specific SFRs (SSFR; i.e., SFR/M * ), and distances with respect to the main sequence (MS) of the SFR-M * plane (i.e., ?log(SSFR) MS = log[SSFR(galaxy)/SSFR MS (M * ,z)]). The T dust -SSFR and T dust – ?log(SSFR) MS correlations are statistically much more significant than the T dust -L IR one. While the slopes of these three correlations are redshift-independent, their normalisations evolve smoothly from z = 0 and z ~ 2. We convert these results into a recipe to derive T dust from SFR, M * and z, valid out to z ~ 2 and for the stellar mass and SFR range covered by our stacking analysis. The existence of a strong T dust -?log(SSFR) MS correlation provides us with several pieces of information on the dust and gas content of galaxies. Firstly, the slope of the T dust -?log(SSFR) MS correlation can be explained by the increase in the star-formation efficiency (SFE; SFR/M gas ) with ?log(SSFR) MS as found locally by molecular gas studies. Secondly, at fixed ?log(SSFR) MS , the constant dust temperature observed in galaxies probing wide ranges in SFR and M * can be explained by an increase or decrease in the number of star-forming regions with comparable SFE enclosed in them. And thirdly, at high redshift, the normalisation towards hotter dust temperature of the T dust -?log(SSFR) MS correlation can be explained by the decrease in the metallicities of galaxies or by the increase in the SFE of MS galaxies. All these results support the hypothesis that the conditions prevailing in the star-forming regions of MS and far-above-MS galaxies are different. MS galaxies have star-forming regions with low SFEs and thus cold dust, while galaxies situated far above the MS seem to be in a starbursting phase characterised by star-forming regions with high SFEs and thus hot dust.

History

Publication status

  • Published

File Version

  • Published version

Journal

Astronomy and Astrophysics

ISSN

0004-6361

Publisher

EDP Sciences

Volume

561

Article number

A86

Department affiliated with

  • Physics and Astronomy Publications

Full text available

  • Yes

Peer reviewed?

  • Yes

Legacy Posted Date

2015-06-10

First Open Access (FOA) Date

2015-06-10

First Compliant Deposit (FCD) Date

2015-06-10

Usage metrics

    University of Sussex (Publications)

    Categories

    No categories selected

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC