leda Compilation of AGN/Activity classification site

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This catalogue (table a109 in the database) presents the compilation of the activity classification of objects. We have added in the database a characterization of the nuclear activity from the Véron and Véron catalogue (see Véron and Véron 2006 in VizieR, and in ADS , hereafter VCV-12). It is now possible to retrieve an activity type for the HyperLeda galaxies having this attribute, and to select list of objects from constraints on activity type. For example, one may select all Sy2 galaxies within some magnitude limits and/or redshift. The main difficulty for cross-identifying these multi-wavelength catalogues is the extremely different spatial resolution of the surveys which make automatic positional cross-identification unsafe. Fortunately, the VCV-12 already made the essential of this work and provides accurate position (typically to within 1 arcsec) for most of the sources. In many cases the redshift consistency allowed to make the proper identifications, and in some cases it was necessary to control visually the identifications using sky surveys images.

Statistics of the compilation of AGN/Activity classification

The first ten sources of nuclear activity

In the work we have made some differences regarding to VCV-12 catalogue:
(i) For the moment, some objects from VCV-12 are still not cross-identified in HyperLeda;
(ii) For all "types" of BL which exist in VCV-12 (BL, BL?, blank and ? ) we have use the flag BL;
(iii) We denoted as Q all objects brighter than absolute magnitude Mabs=23;