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arXiv · 2203.08539

Galaxy And Mass Assembly (GAMA): Data Release 4 and the z < 0.1 total and z < 0.08 morphological galaxy stellar mass functions

Abstract

In Galaxy And Mass Assembly Data Release 4 (GAMA DR4), we make available our full spectroscopic redshift sample. This includes 248682 galaxy spectra, and, in combination with earlier surveys, results in 330542 redshifts across five sky regions covering ~250deg^2. The redshift density, is the highest available over such a sustained area, has exceptionally high completeness (95 per cent to r_KIDS=19.65mag), and is well suited for the study of galaxy mergers, galaxy groups, and the low redshift (z<0.25) galaxy population. DR4 includes 32 value-added tables or Data Management Units (DMUs) that provide a number of measured and derived data products including GALEX, ESO KiDS, ESO VIKING, WISE and Herschel Space Observatory imaging. Within this release, we provide visual morphologies for 15330 galaxies to z<0.08, photometric redshift estimates for all 18million objects to r_KIDS~25mag, and stellar velocity dispersions for 111830 galaxies. We conclude by deriving the total galaxy stellar mass function (GSMF) and its sub-division by morphological class (elliptical, compact-bulge and disc, diffuse-bulge and disc, and disc only). This extends our previous measurement of the total GSMF down to 10^6.75 M_sol h^-2_70 and we find a total stellar mass density of rho_*=(2.97+/-0.04)x10^8 M_sol h_70 Mpc^-3 or Omega_*=(2.17+/-0.03)x10^-3 h^-1_70. We conclude that at z<0.1, the Universe has converted 4.9+/-0.1 per cent of the baryonic mass implied by Big Bang Nucleosynthesis into stars that are gravitationally bound within the galaxy population.

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Simon P. Driver, Sabine Bellstedt, Aaron S. G. Robotham, Ivan K. Baldry, Luke J. Davies, Jochen Liske, Danail Obreschkow, Edward N. Taylor, Angus H. Wright, Mehmet Alpaslan, Steven P. Bamford, Amanda E. Bauer, Joss Bland-Hawthorn, Maciej Bilicki, Matias Bravo, Sarah Brough, Sarah Casura, Michelle E. Cluver, Matthew Colless, Christopher J. Conselice, Scott M. Croom, Jelte de Jong, Franceso D'Eugenio, Roberto De Propris, Burak Dogruel, Michael J. Drinkwater, Andrej Dvornik, Daniel J. Farrow, Carlos S. Frenk, Benjamin Giblin, Alister W. Graham, Meiert W. Grootes, Madusha L. P. Gunawardhana, Abdolhosein Hashemizadeh, Boris Haussler, Catherine Heymans, Hendrik Hildebrandt, Benne W. Holwerda, Andrew M. Hopkins, Tom H. Jarrett, D. Heath Jones, Lee S. Kelvin, Soheil Koushan, Konrad Kuijken, Maritza A. Lara-Lopez, Rebecca Lange, Angel R. Lopez-Sanchez, Jon Loveday, Smriti Mahajan, Martin Meyer, Amanda J. Moffett, Nicola R. Napolitano, Peder Norberg, Matt S. Owers, Mario Radovich, Mojtaba Raouf, John A. Peacock, Steven Phillipps, Kevin A. Pimbblet, Cristina Popescu, Khaled Said, Anne E. Sansom, Mark Seibert, Will J. Sutherland, Jessica E. Thorne, Richard J. Tuffs, Ryan Turner, Arjen van der Wel, Eelco van Kampen, Steve M. Wilkins. 2022-03-16. Galaxy And Mass Assembly (GAMA): Data Release 4 and the z < 0.1 total and z < 0.08 morphological galaxy stellar mass functions. https://doi.org/10.1093/mnras/stac472

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