Presentation 1 : Poster
HyperLeda
Prugniel & Paturel
The HyperLeda project is driven by astronomical objectives: (1) studying the
distribution of galaxies in the Local Universe (distance scale, luminosity
function, environment) and (2) studying the evolution of the stellar populations
in nearby galaxies. The principal need for these projects is an access to
multi-parametric whole sky samples with extended documentation of the biases.
HyperLeda proposes technical solutions to satisfy these needs. First, `raw`
catalogues are produced by uniformizing data extracted from the literature (tables
and measurements found in article are reformatted and converted to common units;
object designations are cross-identified with our master list). The production of
these catalogues is shared between the astronomers of the HyperLeda consortium.
Second, astronomical recipes, as aperture correction, and statistical homogenization
are applied in order to derive the homogeneous set of fundamental parameters that
make the LEDA catalogue.
The LEDA catalogue contains 3 millions objects, 1 million of them of confirmed
nature. 25000 measurements of cz, 3 million fluxes, diameters and position angles,
225000 morphological types and several less frequent parameters, as for example
5000 central velocity dispersion measurements or 2000 kinematical profiles.
HyperLeda offers to the web user access to the raw and homogenized data through
selection from an object designation, a box on a sky or a SQL request composed on
the 30 fundamental parameters plus 70 'derived' parameters. HyperLeda also gives
access to the pixels of the DENIS survey and remote access to other surveys that
can be injected in our on-the-fly data-analysis pipeline.
In the future we plan to develop the possibility to customize the recipes of data
homogenization (ie. give the user the possibility to define its own parameterization)
and weighting of individual datasets or measurements.