Site Map
Contacts
Follow us on Facebook Follow us on Twitter YouTube channel
Centro de Astrofísica da Universidade do Porto

CALIFA, the Calar Alto Legacy Integral Field Area survey:
I. Survey presentation

S. F. Sánchez, R. C Kennicutt, A. Gil de Paz, G. van de Ven, J. M. Vílchez, L. Wisotzki, C. J. Walcher, D. Mast, J. A. L. Aguerri, S. Albiol-Pérez, A. Alonso Herrero, J. Alves, J. Bakos, T. Bartáková, J. Bland-Hawthorn, A. Boselli, D. J. Bomans, A. Castillo-Morales, C. Cortijo-Ferrero, A. de Lorenzo-Cáceres, A. del Olmo, R.-J. Dettmar, A. I. Díaz, S. Ellis, J. Falcón-Barroso, H. Flores, A. Gallazzi, B. García-Lorenzo, R. M. González Delgado, N. Gruel, T. Haines, C. Hao, B. Husemann, J. Iglésias-Páramo, K. Jahnke, B. D. Johnson, B. Jungwiert, V. Kalinova, C. Kehrig, D. Kupko, Á. R. López-Sánchez, M. Lyubenova, R. A. Marino, E. Mármol-Queraltó, I. Márquez, J. Masegosa, S. Meidt, J. Méndez-Abreu, A. Monreal Ibero, C. Montijo, A. M. Mourão, G. Palacios-Navarro, P. Papaderos, A. Pasquali, R. Peletier, E. Pérez, I. Pérez, A. Quirrenbach, M. Relaño, F. F. Rosales-Ortega, M. M. Roth, T. Ruiz-Lara, P. Sánchez-Blázquez, C. Sengupta, R. Singh, V. Stanishev, S. C. Trager, A. Vazdekis, K. Viironen, V. Wild, S. Zibetti, B. Ziegler

Abstract
The final product of galaxy evolution through cosmic time is the population of galaxies in the Local Universe. These galaxies are also those that can be studied in most detail, thus providing a stringent benchmark for our understanding of galaxy evolution. Through the huge success of spectroscopic single-fiber, statistical surveys of the Local Universe in the last decade, it has become clear, however, that an authoritative observational description of galaxies will involve measuring their spatially resolved properties over their full optical extent (covering D25) for a statistically significant sample.We present here the Calar Alto Legacy Integral Field Area (CALIFA) survey, which has been designed to provide a first step in this direction.We summarize the survey goals and design, including sample selection and observational strategy.We also showcase the data taken during the first observing runs (June/July 2010) and outline the reduction pipeline, quality control schemes and general characteristics of the reduced data.
This survey is obtaining spatially resolved spectroscopic information of a diameter selected sample of ∼600 galaxies in the Local Universe (0.005< z < 0.03). CALIFA has been designed to allow the building of two-dimensional maps of the following quantities: (a) stellar populations: ages and metallicities; (b) ionized gas: distribution, excitation mechanism and chemical abundances; and (c) kinematic properties: both from stellar and ionized gas components. CALIFA uses the PPAK Integral Field Unit (IFU), with a hexagonal field-of-view of ∼1.3 arcmin2, with a 100% covering factor by adopting a three-pointing dithering scheme. The optical wavelength range is covered from 3700 to 7000 Å, using two overlapping setups (V500 and V1200), with different resolutions: R∼850 and R∼1650, respectively. CALIFA is a legacy survey, intended for the community. The reduced data will be released, once the quality has been guaranteed.
The analyzed data fulfill the expectations of the original observing proposal, on the basis of a set of quality checks and exploratory analysis: (i) the final datacubes reach a 3σ limiting surface brightness depth of ∼ 23.0 mag/arcsec2 for the V500 grating data (∼22.8 mag/arcsec2 for V1200); (ii) about ∼70% of the covered field-of-view is above this 3σ limit; (iii) the data have a blue-to-red relative flux calibration within a few percent in most of the wavelength range; (iv) the absolute flux calibration is accurate within ∼8% with respect to SDSS; (v) the measured spectral resolution is ∼85 km s-1 for V1200 (∼150 km s-1 for V500); (vi) the estimated accuracy of the wavelength calibration is ∼5 km s-1 for the V1200 data (∼10 km s-1 for the V500 data); (vii) the aperture matched CALIFA and SDSS spectra are qualitatively and quantitatively similar. Finally, we show that we are able to carry out all measurements indicated above, recovering the properties of the stellar populations, the ionized gas and the kinematics of both components. The associated maps illustrate the spatial variation of these parameters across the field, reemphasizing the redshift dependence of single aperture spectroscopic measurements.We conclude from this first look at the data that CALIFA will be an important resource for archaeological studies of galaxies in the Local Universe.

Keywords
techniques: spectroscopic – galaxies: active – galaxies: evolution – surveys – galaxies: ISM – galaxies: stellar content

Notes
Based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck-Institut für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC).

Astronomy and Astrophysics
Volume 538, Page A8_1
February 2012

>> ADS>> DOI

Institute of Astrophysics and Space Sciences

Institute of Astrophysics and Space Sciences (IA) is a new but long anticipated research infrastructure with a national dimension. It embodies a bold but feasible vision for the development of Astronomy, Astrophysics and Space Sciences in Portugal, taking full advantage and fully realizing the potential created by the national membership of the European Space Agency (ESA) and the European Southern Observatory (ESO). IA resulted from the merging the two most prominent research units in the field in Portugal: the Centre for Astrophysics of the University of Porto (CAUP) and the Center for Astronomy and Astrophysics of the University of Lisbon (CAAUL). It currently hosts more than two-thirds of all active researchers working in Space Sciences in Portugal, and is responsible for an even greater fraction of the national productivity in international ISI journals in the area of Space Sciences. This is the scientific area with the highest relative impact factor (1.65 times above the international average) and the field with the highest average number of citations per article for Portugal.

Proceed on CAUP's website|Go to IA website