Header

UZH-Logo

Maintenance Infos

The nature of giant clumps in distant galaxies probed by the anatomy of the cosmic snake


Cava, Antonio; Schaerer, Daniel; Richard, Johan; Pérez-González, Pablo G; Dessauges-Zavadsky, Miroslava; Mayer, Lucio; Tamburello, Valentina (2018). The nature of giant clumps in distant galaxies probed by the anatomy of the cosmic snake. Nature Astronomy, 2(1):76-82.

Abstract

Giant stellar clumps are ubiquitous in high-redshift galaxies1,2. They are thought to play an important role in the build-up of galactic bulges3 and as diagnostics of star formation feedback in galactic discs4. Hubble Space Telescope (HST) blank field imaging surveys have estimated that these clumps have masses of up to 109.5 M ⊙ and linear sizes of ≳1 kpc5,6. Recently, gravitational lensing has also been used to get higher spatial resolution7,8,9. However, both recent lensed observations10,11 and models12,13 suggest that the clumps’ properties may be overestimated by the limited resolution of standard imaging techniques. A definitive proof of this observational bias is nevertheless still missing. Here we investigate directly the effect of resolution on clump properties by analysing multiple gravitationally lensed images of the same galaxy at different spatial resolutions, down to 30 pc. We show that the typical mass and size of giant clumps, generally observed at ~1 kpc resolution in high-redshift galaxies, are systematically overestimated. The high spatial resolution data, only enabled by strong gravitational lensing using currently available facilities, support smaller scales of clump formation by fragmentation of the galactic gas disk via gravitational instabilities.

Abstract

Giant stellar clumps are ubiquitous in high-redshift galaxies1,2. They are thought to play an important role in the build-up of galactic bulges3 and as diagnostics of star formation feedback in galactic discs4. Hubble Space Telescope (HST) blank field imaging surveys have estimated that these clumps have masses of up to 109.5 M ⊙ and linear sizes of ≳1 kpc5,6. Recently, gravitational lensing has also been used to get higher spatial resolution7,8,9. However, both recent lensed observations10,11 and models12,13 suggest that the clumps’ properties may be overestimated by the limited resolution of standard imaging techniques. A definitive proof of this observational bias is nevertheless still missing. Here we investigate directly the effect of resolution on clump properties by analysing multiple gravitationally lensed images of the same galaxy at different spatial resolutions, down to 30 pc. We show that the typical mass and size of giant clumps, generally observed at ~1 kpc resolution in high-redshift galaxies, are systematically overestimated. The high spatial resolution data, only enabled by strong gravitational lensing using currently available facilities, support smaller scales of clump formation by fragmentation of the galactic gas disk via gravitational instabilities.

Statistics

Citations

Dimensions.ai Metrics
23 citations in Web of Science®
19 citations in Scopus®
Google Scholar™

Altmetrics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Institute for Computational Science
Dewey Decimal Classification:530 Physics
Language:English
Date:1 January 2018
Deposited On:01 Mar 2019 14:39
Last Modified:22 Sep 2019 06:01
Publisher:Springer
ISSN:2397-3366
OA Status:Closed
Free access at:Related URL. An embargo period may apply.
Publisher DOI:https://doi.org/10.1038/s41550-017-0295-x
Related URLs:https://www.zora.uzh.ch/id/eprint/143811/

Download

Full text not available from this repository.
View at publisher

Get full-text in a library