Jimenez-Andrade, E. F., Magnelli, B., Karim, A., Zamorani, G., Bondi, M., Schinnerer, E., Sargent, M., Romano-Diaz, E., Novak, M., Lang, P., Bertoldi, F., Vardoulaki, E., Toft, S., Smolcic, V., Harrington, K., Leslie, S., Delhaize, J., Liu, D., Karoumpis, C., Kartaltepe, J. and Koekemoer, A. M. (2019). Radio continuum size evolution of star-forming galaxies over 0.35 < z < 2.25. Astron. Astrophys., 625. LES ULIS CEDEX A: EDP SCIENCES S A. ISSN 1432-0746

Full text not available from this repository.

Abstract

To better constrain the physical mechanisms driving star formation, we present the first systematic study of the radio continuum size evolution of star-forming galaxies (SFGs) over the redshift range 0.35 < z < 2.25. We use the VLA COSMOS 3 GHz map (noise rms = 2.3 mu Jy beam(-1), theta(beam) = 0.75 arcsec) to construct a mass-complete sample of 3184 radio-selected SFGs that reside on and above the main sequence (MS) of SFGs. We constrain the overall extent of star formation activity in galaxies by applying a 2D Gaussian model to their radio continuum emission. Extensive Monte Carlo simulations are used to validate the robustness of our measurements and characterize the selection function. We find no clear dependence between the radio size and stellar mass, M-star, of SFGs with 10.5 less than or similar to log(M-star/M-circle dot) less than or similar to 11.5. Our analysis suggests that MS galaxies are preferentially extended, while SFGs above the MS are always compact. The median effective radius of SFGs on (above) the MS of R-eff = 1.5 +/- 0.2 (1.0 +/- 0.2) kpc remains nearly constant with cosmic time; a parametrization of the form R-eff proportional to (1 + z)(alpha) yields a shallow slope of only alpha = -0.26 +/- 0.08 (0.12 +/- 0.14) for SFGs on (above) the MS. The size of the stellar component of galaxies is larger than the extent of the radio continuum emission by a factor similar to 2 (1.3) at z = 0.5 (2), indicating star formation is enhanced at small radii. The galactic-averaged star formation rate surface density (Sigma(SFR)) scales with the distance to the MS, except for a fraction of MS galaxies (less than or similar to 10%) that harbor starburst-like Sigma(SFR). These hidden starbursts might have experienced a compaction phase due to disk instability and/or a merger-driven burst of star formation, which may or may not significantly offset a galaxy from the MS. We thus propose to use Sigma(SFR) and distance to the MS in conjunction to better identify the galaxy population undergoing a starbursting phase.

Item Type: Journal Article
Creators:
CreatorsEmailORCIDORCID Put Code
Jimenez-Andrade, E. F.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Magnelli, B.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Karim, A.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Zamorani, G.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Bondi, M.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Schinnerer, E.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Sargent, M.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Romano-Diaz, E.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Novak, M.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Lang, P.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Bertoldi, F.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Vardoulaki, E.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Toft, S.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Smolcic, V.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Harrington, K.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Leslie, S.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Delhaize, J.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Liu, D.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Karoumpis, C.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Kartaltepe, J.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Koekemoer, A. M.UNSPECIFIEDUNSPECIFIEDUNSPECIFIED
URN: urn:nbn:de:hbz:38-147949
DOI: 10.1051/0004-6361/201935178
Journal or Publication Title: Astron. Astrophys.
Volume: 625
Date: 2019
Publisher: EDP SCIENCES S A
Place of Publication: LES ULIS CEDEX A
ISSN: 1432-0746
Language: English
Faculty: Unspecified
Divisions: Unspecified
Subjects: no entry
Uncontrolled Keywords:
KeywordsLanguage
DEEP FIELD; MAIN-SEQUENCE; SUBMILLIMETER GALAXIES; PHYSICAL-PROPERTIES; COMPACT GALAXIES; FORMATION RATES; LEGACY SURVEY; SIMPLE-MODEL; S-COSMOS; MASSMultiple languages
Astronomy & AstrophysicsMultiple languages
Refereed: Yes
URI: http://kups.ub.uni-koeln.de/id/eprint/14794

Downloads

Downloads per month over past year

Altmetric

Export

Actions (login required)

View Item View Item