Fornax3D project: Assembly history of massive early-type galaxies in the Fornax cluster from deep imaging and integral field spectroscopy

¹ INAF–Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, 80131 Napoli, Italy
e-mail: marilena.spavone@inaf.it
² Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22, Chile
³ Department of Astrophysics, University of Vienna, Tuerkenschanzstrasse 17, 1180 Vienna, Austria
⁴ Instituto de Astronomía y Ciencias Planetarias, Avenida Copayapu 485, Copiapó, Chile
⁵ Dipartimento di Fisica e Astronomia “G. Galilei”, Universitá di Padova, vicolo dell’Osservatorio 3, 35122 Padova, Italy
⁶ INAF–Osservatorio Astronomico di Padova, visolo dell’Osservatorio 5, 35122 Padova, Italy
⁷ Armagh Observatory and Planetarium, College Hill, Armagh BT61 9DG, UK
⁸ European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching bei Muenchen, Germany
⁹ European Space Agency, European Space Research and Technology Centre, Keplerlaan 1, 2200 AG Noordwijk, The Netherlands
¹⁰ Instituto de Astrofísica de Canarias, Vía Láctea s/n, 38205 La Laguna, Tenerife, Spain
¹¹ Departamento de Astrofísica, Universidad de La Laguna, 38200 La Laguna, Tenerife, Spain
¹² Research Centre for Astronomy, Astrophysics, and Astrophotonics, Department of Physics and Astronomy, Macquarie University, Sydney, NSW 2109, Australia
¹³ Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, 69117 Heidelberg, Germany
¹⁴ Centre for Extragalactic Astronomy, University of Durham, Stockton Road, Durham DH1 3LE, UK
¹⁵ Sterrewacht Leiden, Leiden University, Postbus 9513, 2300 RA Leiden, The Netherlands
¹⁶ Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse 1, 85748 Garching bei Muenchen, Germany
¹⁷ Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, PR China

Received: 9 February 2022
Accepted: 27 May 2022

Abstract

This work is based on high-quality integral-field spectroscopic data obtained with the Multi Unit Spectroscopic Explorer (MUSE) on the Very Large Telescope (VLT). The 21 brightest (m_B ≤ 15 mag) early-type galaxies (ETGs) inside the virial radius of the Fornax cluster are observed out to distances of ∼2−3 R_e. Deep imaging from the VLT Survey Telescope (VST) is also available for the sample ETGs. We investigated the variation of the galaxy structural properties as a function of the total stellar mass and cluster environment. Moreover, we correlated the size scales of the luminous components derived from a multi-component decomposition of the VST surface-brightness radial profiles of the sample ETGs with the MUSE radial profiles of stellar kinematic and population properties. The results are compared with both theoretical predictions and previous observational studies and used to address the assembly history of the massive ETGs of the Fornax cluster. We find that galaxies in the core and north-south clump of the cluster, which have the highest accreted mass fraction, show milder metallicity gradients in their outskirts than the galaxies infalling into the cluster. We also find a segregation in both age and metallicity between the galaxies belonging to the core and north-south clump and the infalling galaxies. The new findings fit well within the general framework for the assembly history of the Fornax cluster.