Bar pattern speeds in CALIFA galaxies. I. Fast bars across the Hubble sequence

Author(s)

J. A. L. Aguerri, J. Méndez-Abreu, J. Falcón-Barroso, A. Amorin, J. Barrera-Ballesteros, R. Cid Fernandes, R. García-Benito, B. García-Lorenzo, R. M. González Delgado, B. Husemann, V. Kalinova, M. Lyubenova, R. A. Marino, I. Márquez, D. Mast, E. Pérez, S. F. Sánchez, G. van de Ven, C. J. Walcher, N. Backsmann, C. Cortijo-Ferrero, J. Bland-Hawthorn, A. del Olmo, J. Iglesias-Páramo, I. Pérez, P. Sánchez-Blázquez, L. Wisotzki, B. Ziegler

Abstract

Context. The bar pattern speed (Ωb) is defined as the

rotational frequency of the bar, and it determines the bar dynamics.

Several methods have been proposed for measuring Ωb.

The non-parametric method proposed by Tremaine & Weinberg (1984,

ApJ, 282, L5; TW) and based on stellar kinematics is the most accurate.

This method has been applied so far to 17 galaxies, most of them SB0 and

SBa types. Aims: We have applied the TW method to a new sample of

15 strong and bright barred galaxies, spanning a wide range of

morphological types from SB0 to SBbc. Combining our analysis with

previous studies, we investigate 32 barred galaxies with their pattern

speed measured by the TW method. The resulting total sample of barred

galaxies allows us to study the dependence of Ωb on

galaxy properties, such as the Hubble type. Methods: We measured

Ωb using the TW method on the stellar velocity maps

provided by the integral-field spectroscopy data from the CALIFA survey.

Integral-field data solve the problems that long-slit data present when

applying the TW method, resulting in the determination of more accurate

Ωb. In addition, we have also derived the ratio ℛ

of the corotation radius to the bar length of the galaxies. According to

this parameter, bars can be classified as fast (ℛ <1.4) and

slow (ℛ > 1.4). Results: For all the galaxies, ℛ

is compatible within the errors with fast bars. We cannot rule out (at

95% level) the fast bar solution for any galaxy. We have not observed

any significant trend between ℛ and the galaxy morphological type.

Conclusions: Our results indicate that independent of the Hubble

type, bars have been formed and then evolve as fast rotators. This

observational result will constrain the scenarios of formation and

evolution of bars proposed by numerical simulations.

Organisation(s)

Department of Astrophysics

External organisation(s)

Institute of Astrophysics of the Canary Islands, University of La Laguna, University of St. Andrews, Universidade Federal de Santa Catarina, Instituto de Astrofísica de Andalucía (CSIC), Leibniz-Institut für Astrophysik Potsdam, Max-Planck-Institut für Astronomie, Universidad Complutense de Madrid, Centro Brasileiro de Pesquisas Físicas (CBPF), Centro Astronómico Hispano Alemán (CAHA), The University of Sydney, Universidad de Granada, Universidad Autónoma de Madrid

Journal

Astronomy & Astrophysics

Volume

576

ISSN

0004-6361

Publication date

04-2015

Peer reviewed

Yes

Austrian Fields of Science 2012

103003 Astronomy, 103004 Astrophysics

Keywords

ASJC Scopus subject areas

Astronomy and Astrophysics, Space and Planetary Science

Portal url

https://ucrisportal.univie.ac.at/en/publications/5fc7cf4b-7ba4-4ae2-b1c1-673c4793070a