Symeonidis, M., Vaccari, M., Berta, S., Page, M. J., Lutz, D., Arumugam, V., Aussel, H., Bock, J., Boselli, A., Buat, V., Capak, P. L., Clements, D. L., Conley, A., Conversi, L., Cooray, A., Dowell, C. D., Farrah, D., Franceschini, A., Giovannoli, E., Glenn, J., Griffin, Matthew Joseph ![]() |
Abstract
Using Herschel data from the deepest SPIRE and PACS surveys (HerMES and PEP) in COSMOS, GOODS-S and GOODS-N, we examine the dust properties of infrared (IR)-luminous (LIR > 1010 L⊙) galaxies at 0.1 < z < 2 and determine how these evolve with cosmic time. The unique angle of this work is the rigorous analysis of survey selection effects, making this the first study of the star-formation-dominated, IR-luminous population within a framework almost entirely free of selection biases. We find that IR-luminous galaxies have spectral energy distributions (SEDs) with broad far-IR peaks characterized by cool/extended dust emission and average dust temperatures in the 25–45 K range. Hot (T > 45 K) SEDs and cold (T < 25 K), cirrus-dominated SEDs are rare, with most sources being within the range occupied by warm starbursts such as M82 and cool spirals such as M51. We observe a luminosity–temperature (L-T) relation, where the average dust temperature of log [LIR/L⊙] ∼ 12.5 galaxies is about 10 K higher than that of their log [LIR/L⊙] ∼ 10.5 counterparts. However, although the increased dust heating in more luminous systems is the driving factor behind the L-T relation, the increase in dust mass and/or starburst size with luminosity plays a dominant role in shaping it. Our results show that the dust conditions in IR-luminous sources evolve with cosmic time: at high redshift, dust temperatures are on average up to 10 K lower than what is measured locally (z ≲ 0.1). This is manifested as a flattening of the L-T relation, suggesting that (ultra)luminous infrared galaxies [(U)LIRGs] in the early Universe are typically characterized by a more extended dust distribution and/or higher dust masses than local equivalent sources. Interestingly, the evolution in dust temperature is luminosity dependent, with the fraction of LIRGs with T < 35 K showing a two-fold increase from z ∼ 0 to z ∼ 2, whereas that of ULIRGs with T < 35 K shows a six-fold increase. Our results suggest a greater diversity in the IR-luminous population at high redshift, particularly for ULIRGs.
Item Type: | Article |
---|---|
Date Type: | Publication |
Status: | Published |
Schools: | Physics and Astronomy |
Subjects: | Q Science > QB Astronomy |
Uncontrolled Keywords: | galaxies: evolution – galaxies ; high-redshift – galaxies ; starburst – infrared ; galaxies – submillimetre ; galaxies |
Publisher: | Oxford University Press |
ISSN: | 0035-8711 |
Funders: | STFC |
Last Modified: | 24 Oct 2022 10:56 |
URI: | https://orca.cardiff.ac.uk/id/eprint/46471 |
Citation Data
Cited 132 times in Scopus. View in Scopus. Powered By Scopus® Data
Actions (repository staff only)
![]() |
Edit Item |