The SAMI Galaxy Survey:spatially resolving the environmental quenching of star formation in GAMA galaxies

• Published in: Monthly Notices of the Royal Astronomical Society
• Main Authors: Schaefer, A. L., Croom, S. M., Norberg, P., Alpaslan, M., Bauer, A. E., Bekki, K., Bland-Hawthorn, J., Bloom, J. V., Bryant, J. J., Couch, W. J., Driver, S. P., Fogarty, L. M. R., Allen, J. T., Foster, C., Goldstein, G., Green, A. W., Hopkins, A. M., Konstantopoulos, I. S., Lawrence, J. S., López-Sánchez, A. R., Lorente, N. P. F., Owers, M. S., Sharp, R., Brough, S., Sweet, S. M., Taylor, E. N., van de Sande, J., Walcher, C. J., Wong, O. I., Medling, A. M., Ho, I. -T., Scott, N., Richards, S. N., Pracy, M. B., Gunawardhana, M. L. P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2017
• Subjects: galaxies: evolution; galaxies: general; galaxies: interactions; galaxies: statistics; galaxies: stellar content; galaxies: structure; sami
• Online Access: https://researchers.mq.edu.au/en/publications/c5f649c3-f707-43b3-9cbd-2accef64fff9; https://doi.org/10.1093/mnras/stw2289; http://purl.org/au-research/grants/arc/CE110001020; http://purl.org/au-research/grants/arc/FT100100457; http://purl.org/au-research/grants/arc/FT140101166; http://purl.org/au-research/grants/arc/FT140100255; http://purl.org/au-research/grants/arc/FL140100278; https://ulrichsweb.serialssolutions.com/title/1509323125112/39424; http://www.scopus.com/inward/record.url?scp=85014748679&partnerID=8YFLogxK

We use data from the Sydney-AAO Multi-Object Integral Field Spectrograph Galaxy Survey and the Galaxy And Mass Assembly (GAMA) survey to investigate the spatially resolved signatures of the environmental quenching of star formation in galaxies. Using dust-corrected measurements of the distribution of Hα emission, we measure the radial profiles of star formation in a sample of 201 star-forming galaxies covering three orders of magnitude in stellar mass (M*; 10⁸˙¹–10¹⁰˙⁹⁵M⊙) and in fifth nearest neighbour local environment density (Σ5; 10⁻¹˙³–10²˙¹Mpc⁻²). We show that star formation rate gradients in galaxies are steeper in dense (log₁₀(Σ₅/Mpc²) > 0.5) environments by 0.58±0.29dex rₑ⁻¹ in galaxies with stellar masses in the range 10¹⁰ 1.0). These lines of evidence strongly suggest that with increasing local environment density, the star formation in galaxies is suppressed, and that this starts in their outskirts such that quenching occurs in an outside-in fashion in dense environments and is not instantaneous.