The SAMI Galaxy Survey: understanding observations of large-scale outflows at low redshift with EAGLE simulations

Tescari, E.; Cortese, L.; Power, C.; Wyithe, J.S.B.; Ho, I.-T.; Crain, R.A.; Bland-Hawthorn, J.; Croom, S.M.; Kewley, L.J.; Schaye, J.; Bower, R.G.; Theuns, T.; Schaller, M.; Barnes, L.; Brough, S.; Bryant, J.J.; Goodwin, M.; Gunawardhana, M.L.P.; Lawrence, J.S.; Leslie, S.K.; López-Sánchez, Á. R.; Lorente, N.P.F.; Medling, A.M.; Richards, S.N.; Sweet, S.M.; Tonini, C.

doi:10.1093/mnras/stx2315

The SAMI Galaxy Survey: understanding observations of large-scale outflows at low redshift with EAGLE simulations

Tescari, E.; Cortese, L.; Power, C.; Wyithe, J.S.B.; Ho, I.-T.; Crain, R.A.; Bland-Hawthorn, J.; Croom, S.M.; Kewley, L.J.; Schaye, J.; Bower, R.G.; Theuns, T.; Schaller, M.; Barnes, L.; Brough, S.; Bryant, J.J.; Goodwin, M.; Gunawardhana, M.L.P.; Lawrence, J.S.; Leslie, S.K.; López-Sánchez, Á. R.; Lorente, N.P.F.; Medling, A.M.; Richards, S.N.; Sweet, S.M.; Tonini, C.

Authors

E. Tescari

L. Cortese

C. Power

J.S.B. Wyithe

I.-T. Ho

R.A. Crain

J. Bland-Hawthorn

S.M. Croom

L.J. Kewley

J. Schaye

R.G. Bower

Professor Tom Theuns tom.theuns@durham.ac.uk
Professor

Dr Matthieu Schaller matthieu.schaller@durham.ac.uk
Academic Visitor

L. Barnes

S. Brough

J.J. Bryant

M. Goodwin

M.L.P. Gunawardhana

J.S. Lawrence

S.K. Leslie

Á. R. López-Sánchez

N.P.F. Lorente

A.M. Medling

S.N. Richards

S.M. Sweet

C. Tonini

Abstract

This work presents a study of galactic outflows driven by stellar feedback. We extract main-sequence disc galaxies with stellar mass 109 ≤ M⋆/ M⊙ ≤ 5.7 × 1010 at redshift z = 0 from the highest resolution cosmological simulation of the Evolution and Assembly of GaLaxies and their Environments (EAGLE) set. Synthetic gas rotation velocity and velocity dispersion (σ) maps are created and compared to observations of disc galaxies obtained with the Sydney-AAO (Australian Astronomical Observatory) Multi-object Integral field spectrograph (SAMI), where σ-values greater than 150 km s−1 are most naturally explained by bipolar outflows powered by starburst activity. We find that the extension of the simulated edge-on (pixelated) velocity dispersion probability distribution depends on stellar mass and star formation rate surface density (ΣSFR), with low-M⋆/low-ΣSFR galaxies showing a narrow peak at low σ (∼30 km s−1) and more active, high-M⋆/high-ΣSFR galaxies reaching σ > 150 km s−1. Although supernova-driven galactic winds in the EAGLE simulations may not entrain enough gas with T <105 K compared to observed galaxies, we find that gas temperature is a good proxy for the presence of outflows. There is a direct correlation between the thermal state of the gas and its state of motion as described by the σ-distribution. The following equivalence relations hold in EAGLE: (i) low-σ peak ⇔ disc of the galaxy ⇔ gas with T <105 K; (ii) high-σ tail ⇔ galactic winds ⇔ gas with T ≥105 K.

Citation

Tescari, E., Cortese, L., Power, C., Wyithe, J., Ho, I., Crain, R., …Tonini, C. (2018). The SAMI Galaxy Survey: understanding observations of large-scale outflows at low redshift with EAGLE simulations. Monthly Notices of the Royal Astronomical Society, 473(1), 380-397. https://doi.org/10.1093/mnras/stx2315

Journal Article Type	Article
Acceptance Date	Sep 5, 2017
Online Publication Date	Sep 9, 2017
Publication Date	Jan 1, 2018
Deposit Date	Jan 16, 2018
Publicly Available Date	Jan 17, 2018
Journal	Monthly Notices of the Royal Astronomical Society
Print ISSN	0035-8711
Electronic ISSN	1365-2966
Publisher	Royal Astronomical Society
Peer Reviewed	Peer Reviewed
Volume	473
Issue	1
Pages	380-397
DOI	https://doi.org/10.1093/mnras/stx2315
Related Public URLs	https://arxiv.org/abs/1709.01939

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Copyright Statement
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2017 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.