Swinburne
Browse

The SLUGGS survey: outer triaxiality of the fast rotator elliptical NGC 4473

Download (706.57 kB)
journal contribution
posted on 2024-07-11, 07:05 authored by C. Foster, J. A. Arnold, Duncan ForbesDuncan Forbes, N. Pastorello, A. J. Romanowsky, L. R. Spitler, J. Strader, Jean BrodieJean Brodie
Systematic surveys of nearby early-type galaxies using integral field unit (IFU) spectrograph data have revealed that galaxies can hide interesting structures only visible through kinematic studies. As part of their pioneering work, the ATLAS3D team have shown that most morphologically elliptical galaxies are centrally kinematically disc like. Hence, while global morphology suggests that ellipticals are ellipsoidal/triaxial in shape, their central kinematics may be consistent with (inclined) oblate systems. Here, we study the fast rotator elliptical galaxy: NGC 4473. Using slitlets, we obtain galaxy light kinematics out to unprecedentedly large galactocentric radii (2.5 effective radii). While we confirm the IFU results in the central regions, we find that at large galactocentric radii NGC 4473 exhibits a kinematic transition. In the outskirts, we observe clear minor and major axis rotation, a tell-tale sign of triaxiality, which agrees well with the galaxy's Hubble type. This outer 'kinematically distinct halo' may be expected from simulations of galaxy formation, and in this system contains around one-third of the stellar light. While this galaxy may be a special case, it suggests that further investigation of the outskirts of galaxies is needed to confirm the new paradigm of galaxy classification.

Funding

Revealing how elliptical galaxies formed

Australian Research Council

Find out more...

History

Available versions

PDF (Published version)

ISSN

0035-8711

Journal title

Monthly Notices of the Royal Astronomical Society

Volume

435

Issue

4

Pagination

4 pp

Publisher

Oxford University Press

Copyright statement

Copyright © 2013 The authors Published by Oxford University Press on behalf of the Royal Astronomical Society. The published version is reproduced in accordance with the copyright policy of the publisher.

Language

eng

Usage metrics

    Publications

    Keywords

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC