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We propose to observe a statistically well-defined sample of ~600 galaxies in
the local universe using 250 observing nights with the PMAS/PPAK
integral field spectrophotometer, mounted on the Calar Alto 3.5 m
telescope. This survey, termed CALIFA, will provide the largest and most
comprehensive wide-field IFU survey of galaxies carried out to date,
addressing several fundamental issues in galactic structure and evolution. The
defining science drivers for the project are: (a) Model the stellar
population and constrain the star formation histories; (b) trace the
distribution of ionized gas and estimate chemical abundances for the gas
phase; and (c) measure the kinematic properties of the galaxies, both from
emission and from absorption lines; all these quantities will be reconstructed
in maps covering the entire luminous extent of the galaxies in the sample.
The targets for this survey have been selected from the photometric catalog of
the Sloan Digital Sky Survey as a sample limited in apparent isophotal
diameter, such that the PPAK IFU is always optimally filled. An additional
restriction of the covered redshift range to 0.005 < z < 0.03 ensures that all
galaxies can be observed with the same grating settings.
The spectra will be covering the range 3700-7000 AA in two overlapping
setups, one in the red (4300-7000 AA) at a spectral resolution of R=850 and
one in the blue (3700-5000 AA) at R~1650, where the resolutions quoted are
those at the overlapping wavelength range (lambda~4500 A). CALIFA will make
maximal use of the unique capabilities of the PMAS/PPAK instrument. PPAK
offers a combination of extremely wide field-of-view (> 1 arcmin2) with a
high filling factor in one single pointing (65%), good spectral resolution,
and wavelength sensitivity across the optical spectrum. We want to use this
for an unprecedented investigation of emission- and absorption-line mapping of
galaxies simultaneously. The two-dimensional spectral maps obtained for a
large and well-defined sample will provide a powerful follow-up to the much
larger single-aperture studies of the Sloan Digital Sky Survey (SDSS), and
address the fundamental problems of spatial undersampling which have aicted,
not only Sloan, but also other IFU surveys (e.g., the SAURON project). We will
be able to test the assumption of azimuthal symmetry that underlie most single
aperture or long-slit studies of galaxies. In summary, CALIFA will provide a
valuable bridge between large single-aperture surveys such as SDSS and more
detailed studies of individual galaxies with PPAK (e.g: PINGS), SAURON,
VIRUS-P, and other instruments.
A more detail information about the project can be found in the so-call CALIFA's RED BOOK.
As part of the feasibility phase of the project, several objects has been
observed using different PPAK configurations. The data corresponding to these
objects will be make public after the proper quality check.
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