Swinburne
Browse

The first sample of spectroscopically confirmed ultra-compact massive galaxies in the Kilo Degree Survey

Download (6.72 MB)
journal contribution
posted on 2024-08-06, 11:50 authored by C. Tortora, N. R. Napolitano, M. Spavone, F. La Barbera, G. D'Ago, C. Spiniello, K. H. Kuijken, N. Roy, M. A. Raj, S. Cavuoti, M. Brescia, G. Longo, V. Pota, C. E. Petrillo, M. Radovich, F. Getman, L. V.E. Koopmans, I. Trujillo, G. Verdoes Kleijn, M. Capaccioli, A. Grado, G. Covone, D. Scognamiglio, Chris BlakeChris Blake, Karl GlazebrookKarl Glazebrook, Shahab Joudaki, C. Lidman, C. Wolf
We present results from an ongoing investigation using the Kilo Degree Survey (KiDS) on the VLT Survey Telescope (VST) to provide a census of ultra-compact massive galaxies (UCMGs), defined as galaxies with stellar masses M* > 8 × 1010M⊙ and effective radii Re < 1.5 kpc. UCMGs, which are expected to have undergone very few merger events, provide a unique view on the accretion history of the most massive galaxies in the Universe. Over an effective sky area of nearly 330 deg2, we select UCMG candidates from KiDS multicolour images, which provide high quality structural parameters, photometric redshifts, and stellar masses. Our sample of ~1000 photometrically selected UCMGs at z < 0.5 represents the largest sample of UCMG candidates assembled to date over the largest sky area. In this paper, we present the first effort to obtain their redshifts using different facilities, starting with first results for 28 candidates with redshifts z < 0.5, obtained at NTT and TNG telescopes.We confirmed, as bona fide UCMGs, 19 out of the 28 candidates with new redshifts. A further 46 UCMG candidates are confirmed with literature spectroscopic redshifts (35 at z < 0.5), bringing the final cumulative sample of spectroscopically confirmed lower-z UCMGs to 54 galaxies, which is the largest sample at redshifts below 0.5. We use these spectroscopic redshifts to quantify systematic errors in our photometric selection, and use these to correct our UCMG number counts. We finally compare the results to independent data sets and simulations.

Funding

Probing dark-matter using strong gravitational lenses: from KiDS to Euclid. : Dutch Research Council | 639.043.308

History

Available versions

PDF (Published version)

ISSN

1365-2966

Journal title

Monthly Notices of the Royal Astronomical Society

Volume

481

Issue

4

Pagination

24 pp

Publisher

Oxford Academic

Copyright statement

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society Copyright © 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.

Language

eng

Usage metrics

    Publications

    Categories

    No categories selected

    Keywords

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC