N. Backsmann

TL;DR: In this paper, the authors describe the selection procedure and statistical properties of the galaxy sample used by the Calar Alto Legacy Integral Field Area (CALIFA) survey, a public legacy survey of 600 galaxies using integral field spectroscopy.

TL;DR: In this article, the authors applied the fossil record method of stellar population spectral synthesis to recover the spatially and time resolved star formation history of each galaxy, and showed that the signal of downsizing is spatially preserved with both inner and outer regions growing faster for more massive galaxies.

Abstract: Context. The bar pattern speed (Ω_b) is defined as the rotational frequency of the bar, and it determines the bar dynamics. Several methods have been proposed for measuring Ω_b. 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 Ω_b on galaxy properties, such as the Hubble type. Methods. We measured Ω_b 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 Ω_b. 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). 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.

TL;DR: In this article, the TW method was applied to a new sample of 15 strong and bright barred galaxies, spanning a wide range of morphological types from SB0 to SBbc.

TL;DR: In this paper, the authors describe the selection procedure and statistical properties of the galaxy sample used by the Calar Alto Legacy Integral Field Area Survey (CALIFA), a public legacy survey of 600 galaxies using integral field spectroscopy.