University of Sussex
Browse
MNRAS-2013-Hopkins-2047-66_(1).pdf (7.38 MB)

Galaxy And Mass Assembly (GAMA): spectroscopic analysis

Download (7.38 MB)
journal contribution
posted on 2023-06-08, 14:46 authored by A M Hopkins, S P Driver, S Brough, M S Owers, A E Bauer, M L P Gunawardhana, M E Cluver, M Colless, C Foster, M A Lara-Lopez, I Roseboom, R Sharp, O Steele, D Thomas, I K Baldry, M J I Brown, J Liske, P Norberg, A S G Robotham, S Bamford, J Bland-Hawthorn, M J Drinkwater, Jonathan LovedayJonathan Loveday, M Meyer, J A Peacock, R Tuffs, N Agius, M Alpaslan, E Andrae, E Cameron, S Cole, J H Y Ching, L Christodoulou, C Conselice, S Croom, N J G Cross, R De Propris, J Delhaize, L Dunne, S Eales, S Ellis, C S Frenk, A W Graham, M W Grootes, B Haussler, C Heymans, D Hill, B Hoyle, M Hudson, M Jarvis, J Johansson, D H Jones, E van Kampen, L Kelvin, K Kuijken, A Lopez-Sanchez, S Maddox, B Madore, C Maraston, T McNaught-Roberts, R C Nichol, Seb OliverSeb Oliver, H Parkinson, S Penny, S Phillipps, K A Pimbblet, T Ponman, C C Popescu, M Prescott, R Proctor, E M Sadler, A E Sansom, M Seibert, L Staveley-Smith, W Sutherland, E Taylor, L Van Waerbeke, J A Vazquez-Mata, S Warren, D B Wijesinghe, V Wild, Stephen WilkinsStephen Wilkins
The Galaxy And Mass Assembly (GAMA) survey is a multiwavelength photometric and spectroscopic survey, using the AAOmega spectrograph on the Anglo-Australian Telescope to obtain spectra for up to ~300?000 galaxies over 280 deg2, to a limiting magnitude of rpet < 19.8 mag. The target galaxies are distributed over 0 < z ? 0.5 with a median redshift of z ˜ 0.2, although the redshift distribution includes a small number of systems, primarily quasars, at higher redshifts, up to and beyond z = 1. The redshift accuracy ranges from sv ˜ 50?km s-1 to sv ˜ 100?km s-1 depending on the signal-to-noise ratio of the spectrum. Here we describe the GAMA spectroscopic reduction and analysis pipeline. We present the steps involved in taking the raw two-dimensional spectroscopic images through to flux-calibrated one-dimensional spectra. The resulting GAMA spectra cover an observed wavelength range of 3750 ? ? ? 8850?Å at a resolution of R ˜ 1300. The final flux calibration is typically accurate to 10–20?per?cent, although the reliability is worse at the extreme wavelength ends, and poorer in the blue than the red. We present details of the measurement of emission and absorption features in the GAMA spectra. These measurements are characterized through a variety of quality control analyses detailing the robustness and reliability of the measurements. We illustrate the quality of the measurements with a brief exploration of elementary emission line properties of the galaxies in the GAMA sample. We demonstrate the luminosity dependence of the Balmer decrement, consistent with previously published results, and explore further how Balmer decrement varies with galaxy mass and redshift. We also investigate the mass and redshift dependencies of the [N?II]/Ha versus [O?III]/Hß spectral diagnostic diagram, commonly used to discriminate between star forming and nuclear activity in galaxies.

History

Publication status

  • Published

File Version

  • Published version

Journal

Monthly Notices of the Royal Astronomical Society

ISSN

0035-8711

Publisher

Wiley-Blackwell

Issue

3

Volume

430

Page range

2047-2066

Department affiliated with

  • Physics and Astronomy Publications

Full text available

  • Yes

Peer reviewed?

  • Yes

Legacy Posted Date

2013-04-26

First Open Access (FOA) Date

2016-03-22

First Compliant Deposit (FCD) Date

2016-08-17

Usage metrics

    University of Sussex (Publications)

    Categories

    No categories selected

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC