TY - JOUR
T1 - The SAMI Galaxy Survey
T2 - the link between [α/Fe] and kinematic morphology
AU - Watson, Peter J.
AU - Davies, Roger L.
AU - van de Sande, Jesse
AU - Brough, Sarah
AU - Croom, Scott M.
AU - D'Eugenio, Francesco
AU - Glazebrook, Karl
AU - Groves, Brent
AU - López-Sánchez, Ángel R.
AU - Scott, Nicholas
AU - Vaughan, Sam P.
AU - Walcher, C. Jakob
AU - Bland-Hawthorn, Joss
AU - Bryant, Julia J.
AU - Goodwin, Michael
AU - Lawrence, Jon S.
AU - Lorente, Nuria P.F.
AU - Owers, Matt S.
AU - Richards, Samuel
N1 - Publisher Copyright:
© 2022 The Author(s).
PY - 2022/7/1
Y1 - 2022/7/1
N2 - We explore a sample of 1492 galaxies with measurements of the mean stellar population properties and the spin parameter proxy, λR e , drawn from the SAMI Galaxy Surv e y. We fit a global [ α/ Fe ]-σrelation, finding that [ α/ Fe ] = (0 . 395 ±0 . 010) log 10 ( σ) -(0 . 627 ±0 . 002). We observe an anti-correlation between the residuals Δ [ α/ Fe ] and the inclination-corrected λeo R e , which can be expressed as Δ [ α/ Fe ] = ( -0 . 057 ±0 . 008) λeo R e + (0 . 020 ±0 . 003). The anti-correlation appears to be driven by star-forming galaxies, with a gradient of Δ [ α/ Fe ] ∼( -0 . 121 ±0 . 015) λeo R e , although a weak relationship persists for the subsample of galaxies for which star formation has been quenched. We take this to be confirmation that disc-dominated galaxies have an extended duration of star formation. At a reference velocity dispersion of 200 km s -1 , we estimate an increase in half-mass formation time from ∼0.5 Gyr to ∼1.2 Gyr from low- to high- λeo R e galaxies. Slow rotators do not appear to fit these trends. Their residual α-enhancement is indistinguishable from other galaxies with λeo R e ≲0 . 4, despite being both larger and more massive. This result shows that galaxies with λeo R e ≲ 0 . 4 experience a similar range of star formation histories, despite their different physical structure and angular momentum.
AB - We explore a sample of 1492 galaxies with measurements of the mean stellar population properties and the spin parameter proxy, λR e , drawn from the SAMI Galaxy Surv e y. We fit a global [ α/ Fe ]-σrelation, finding that [ α/ Fe ] = (0 . 395 ±0 . 010) log 10 ( σ) -(0 . 627 ±0 . 002). We observe an anti-correlation between the residuals Δ [ α/ Fe ] and the inclination-corrected λeo R e , which can be expressed as Δ [ α/ Fe ] = ( -0 . 057 ±0 . 008) λeo R e + (0 . 020 ±0 . 003). The anti-correlation appears to be driven by star-forming galaxies, with a gradient of Δ [ α/ Fe ] ∼( -0 . 121 ±0 . 015) λeo R e , although a weak relationship persists for the subsample of galaxies for which star formation has been quenched. We take this to be confirmation that disc-dominated galaxies have an extended duration of star formation. At a reference velocity dispersion of 200 km s -1 , we estimate an increase in half-mass formation time from ∼0.5 Gyr to ∼1.2 Gyr from low- to high- λeo R e galaxies. Slow rotators do not appear to fit these trends. Their residual α-enhancement is indistinguishable from other galaxies with λeo R e ≲0 . 4, despite being both larger and more massive. This result shows that galaxies with λeo R e ≲ 0 . 4 experience a similar range of star formation histories, despite their different physical structure and angular momentum.
KW - galaxies: evolution
KW - galaxies: formation
KW - galaxies: kinematics and dynamics
KW - galaxies: stellar content
UR - http://www.scopus.com/inward/record.url?scp=85133139210&partnerID=8YFLogxK
U2 - 10.1093/mnras/stac1221
DO - 10.1093/mnras/stac1221
M3 - Article
SN - 0035-8711
VL - 513
SP - 5076
EP - 5087
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -