This paper describes the Second Public Data Release (DR2) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. The data for 200 objects are made public, including the 100 galaxies of the First Public Data Release (DR1). Data were obtained with the integral-field spectrograph PMAS/PPak mounted on the 3.5 m telescope at the Calar Alto

The discrepancy between abundances computed using optical recombination lines and collisionally excited lines is a major unresolved problem in nebular astrophysics. Here, we show that the largest abundance discrepancies are reached in planetary nebulae with close binary central stars. We illustrate this using deep spectroscopy of three nebulae with

The relation between galaxies and dark matter haloes is of vital importance for evaluating theoretical predictions of structure formation and galaxy formation physics. We use hydrodynamic cosmological simulations of the Local Group to show that the widely used method of abundance matching based on dark matter only simulations fails at the low-mass

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

Roque de los Muchachos Observatory (La Palma) and Teide Observatory (Tenerife) are prime astronomical sites, as confirmed by more than 30 years of intensive site-testing campaigns. The IAC has long been aware of the importance of promoting initiatives for the characterization and protection of the Canarian Observatories. For this purpose, in the

The location of Izaña (Tenerife, Canary Islands) has been proposed for hosting the Cherenkov Telescope Array (CTA). To support the site-testing campaign, we obtained climate normals from the 10 year long series recorded at Izana by the atmospheric Observatory (CIAI), we have also compared the wind regime with a simultaneous 10 year database at the