Space density distribution of galaxies in the absolute magnitude – rotation velocity plane: a volume-complete Tully-Fisher relation from CALIFA stellar kinematics^⋆

¹ Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany
e-mail: sbekeraite@aip.de
² Dept. Astrofísica, Universidad de La Laguna, C/ Astrofísico Francisco Sánchez, 38205 La Laguna, Tenerife, Spain
³ Instituto de Astrofísica de Canarias, C/Vía Láctea s/n, 38200 La Laguna, Tenerife, Spain
⁴ Max-Planck Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany
⁵ Instituto de Astronomía, Universidad Nacional Autonóma de Mexico, A.P. 70-264, 04510 México, D.F., Mexico
⁶ Instituto de Astrofísica de Andalucía (CSIC), Glorieta de la Astronomía, s/n, 18008 Granada, Spain
⁷ Centro Astronómico Hispano Alemán, Calar Alto, (CSIC-MPG), C/Jesús Durbán Remón 2-2, 04004 Almería, Spain
⁸ Department of Physics, Royal Military College of Canada, PO Box 17000, Station Forces, Kingston, ON, K7K 7B4, Canada
⁹ Kapteyn Astronomical Institute, Rijksuniversiteit Groningen, Postbus 800, 9700 AV Groningen, The Netherlands
¹⁰ University of Vienna, Türkenschanzstr. 17, 1180 Vienna, Austria
¹¹ Institute of Astronomy, School of Physics, University of Sydney, NSW 2006, Australia
¹² Departamento de Astrofísica y CC. de la Atmósfera, Universidad Complutense de Madrid, 28040 Madrid, Spain

Received: 19 September 2015
Accepted: 18 May 2016

Abstract

We measured the distribution in absolute magnitude – circular velocity space for a well-defined sample of 199 rotating galaxies of the Calar Alto Legacy Integral Field Area Survey (CALIFA) using their stellar kinematics. Our aim in this analysis is to avoid subjective selection criteria and to take volume and large-scale structure factors into account. Using stellar velocity fields instead of gas emission line kinematics allows including rapidly rotating early-type galaxies. Our initial sample contains 277 galaxies with available stellar velocity fields and growth curve r-band photometry. After rejecting 51 velocity fields that could not be modelled because of the low number of bins, foreground contamination, or significant interaction, we performed Markov chain Monte Carlo modelling of the velocity fields, from which we obtained the rotation curve and kinematic parameters and their realistic uncertainties. We performed an extinction correction and calculated the circular velocity v_circ accounting for the pressure support of a given galaxy. The resulting galaxy distribution on the M_r−v_circ plane was then modelled as a mixture of two distinct populations, allowing robust and reproducible rejection of outliers, a significant fraction of which are slow rotators. The selection effects are understood well enough that we were able to correct for the incompleteness of the sample. The 199 galaxies were weighted by volume and large-scale structure factors, which enabled us to fit a volume-corrected Tully-Fisher relation (TFR). More importantly, we also provide the volume-corrected distribution of galaxies in the M_r−v_circ plane, which can be compared with cosmological simulations. The joint distribution of the luminosity and circular velocity space densities, representative over the range of −20 > M_r > −22 mag, can place more stringent constraints on the galaxy formation and evolution scenarios than linear TFR fit parameters or the luminosity function alone.