Back to Search Start Over

resolved chemical abundance properties within the interstellar medium of star-forming galaxies at z≈ 1.5.

Authors :
Gillman, S
Puglisi, A
Dudzevičiūtė, U
Swinbank, A M
Tiley, A L
Harrison, C M
Molina, J
Sharples, R M
Bower, R G
Cirasuolo, M
Ibar, Edo
Obreschkow, D
Source :
Monthly Notices of the Royal Astronomical Society; 5/30/2022, Vol. 512 Issue 3, p3480-3499, 20p
Publication Year :
2022

Abstract

We exploit the unprecedented depth of integral field data from the KMOS Ultra-deep Rotational Velocity Survey (KURVS) to analyse the strong (Hα) and forbidden ([N  ii ], [S  ii]) emission line ratios in 22 main-sequence galaxies at |$z\, \approx \, 1.5$|⁠. Using the [N  ii ]/Hα emission-line ratio, we confirm the presence of the stellar mass – gas-phase metallicity relation at this epoch, with galaxies exhibiting on average 0.13 ± 0.04 dex lower gas-phase metallicity (12 + log(O/H)<subscript>M13</subscript>  =  8.40 ± 0.03) for a given stellar mass (log<subscript>10</subscript>(M <subscript>*</subscript>[ M <subscript>⊙</subscript>]  =  10.1 ± 0.1).than local main-sequence galaxies. We determine the galaxy-integrated [S  ii ] doublet ratio, with a median value of [S  ii ]λ6716/λ6731  =  1.26 ± 0.14 equivalent to an electron density of log<subscript>10</subscript>(n <subscript>e</subscript>[cm<superscript>−3</superscript>])  =  1.95 ± 0.12. Utilising CANDELS HST multi-band imaging we define the pixel surface-mass and star-formation rate density in each galaxy and spatially resolve the fundamental metallicity relation at |$z\, \approx \, 1.5$|⁠ , finding an evolution of 0.05 ± 0.01 dex compared to the local relation. We quantify the intrinsic gas-phase metallicity gradient within the galaxies using the [N  ii ]/Hα calibration, finding a median annuli-based gradient of ΔZ/ΔR  =  −0.015 ± 0.005 dex kpc<superscript>−1</superscript>. Finally, we examine the azimuthal variations in gas-phase metallicity, which show a negative correlation with the galaxy integrated star-formation rate surface density (⁠|$r_{\rm s}\,$|   =  −0.40,  p <subscript>s</subscript>  =  0.07) but no connection to the galaxies kinematic or morphological properties nor radial variations in stellar mass surface density or star formation rate surface density. This suggests both the radial and azimuthal variations in interstellar medium properties are connected to the galaxy integrated density of recent star formation. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
00358711
Volume :
512
Issue :
3
Database :
Complementary Index
Journal :
Monthly Notices of the Royal Astronomical Society
Publication Type :
Academic Journal
Accession number :
156326823
Full Text :
https://doi.org/10.1093/mnras/stac580