CALIFA, the Calar Alto Legacy Integral Field Area survey

Abstract

We present the first public data release (DR1) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. It consists of science-grade optical datacubes for the first 100 of eventually 600 nearby (0.005 < z < 0.03) galaxies, obtained with the integral-field spectrograph PMAS/PPak mounted on the 3.5 m telescope at the Calar Alto observatory. The galaxies in DR1 already cover a wide range of properties in color-magnitude space, morphological type, stellar mass, and gas ionization conditions. This offers the potential to tackle a variety of open questions in galaxy evolution using spatially resolved spectroscopy. Two different spectral setups are available for each galaxy, (i) a low-resolution V500 setup covering the nominal wavelength range 3745-7500 Å with a spectral resolution of 6.0 Å (FWHM), and (ii) a medium-resolution V1200 setup covering the nominal wavelength range 3650-4840 Å with a spectral resolution of 2.3 Å (FWHM). We present the characteristics and data structure of the CALIFA datasets that should be taken into account for scientific exploitation of the data, in particular the effects of vignetting, bad pixels and spatially correlated noise. The data quality test for all 100 galaxies showed that we reach a median limiting continuum sensitivity of 1.0 × 10 −18 erg s −1 cm −2 Å −1 arcsec −2 at 5635 Å and 2.2 × 10 −18 erg s −1 cm −2 Å −1 arcsec −2 at 4500 Å for the V500 and V1200 setup respectively, which corresponds to limiting r and g band surface brightnesses of 23.6 mag arcsec −2 and 23.4 mag arcsec −2 , or an unresolved emission-line flux detection limit of roughly 1 × 10 −17 erg s −1 cm −2 arcsec −2 and 0.6 × 10 −17 erg s −1 cm −2 arcsec −2 , respectively. The median spatial resolution is 3. 7, and the absolute spectrophotometric calibration is better than 15% (1σ). We also describe the available interfaces and tools that allow easy access to this first public CALIFA data at http://califa.caha.es/DR1.

The Physical Properties of S0 Galaxy PGC 26218: The Origin of Starburst and Star Formation

“…To reduce the effects of the vignetting on blue part (up to ∼ 4200Å) of the V500 data in some parts of the FoV (see Fig. 11 of Husemann et al (2013)), we combine both setups producing a so-called COMBO datacube. The V1200 spectral resolution is degraded to match the V500 data.…”

“…For the remaining wavelength range, the blue part corresponds to the matched V1200 cube and the red part, to the right of the overlapping region, to the original V500 datacube. More details of the reduction process can be found in Husemann et al (2013), García-Benito et al (2015) and Sánchez et al (2016). The final datacube, corrected for Galactic extinction, fully covers the optical range from 3700 to 7300Å.…”

Ionized gas kinematics of massive elliptical galaxies in CALIFA and in cosmological zoom-in simulations

“…Observations were carried out at low (V500, R ∼ 850 and spectral coverage between 3750 and 7500 Å) and medium (V1200, R ∼ 1700 and spectral coverage between 3700 and 4200 Å) spectral resolution, with each galaxy covered by two to three dithered exposures per mode. Once the raw data were taken, they were processed by the CALIFA pipeline (Husemann et al 2013), which removes cosmic rays, carries out flux calibration and extinction corrections, and interpolates the data onto a 78 × 72 grid. All processed data cubes were made public and provided to the community via regular Data Releases, the final one being the DR3 (Sánchez et al 2016).…”

Properties of galaxies with an offset between the position angles of the major kinematic and photometric axes

“…They compared their kinematical PAs with the photometric PAs from the HyperLeda 1 database and found that the offset between the photometric and kinematic position angles, ∆PA, is observed in both isolated as well as in interacting galaxies. Barrera-Ballesteros et al (2014 determined the offsets between the photometric and kinematic position angles for isolated and interacting or merging galaxies measured by the Calar Alto Legacy Integral Field Area 1 http://leda.univ-lyon1.fr/ (CALIFA) survey (Sánchez et al 2012;Husemann et al 2013;García-Benito et al 2015). They found that ∆PA > 21 • for 43% of the interacting or merging galaxies and for 10% of the isolated galaxies in their sample.…”