How to query the VizieR database

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How to query the VizieR database

• http//vizier.u-strasbg.fr/viz-bin/VizieR

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Search by wavelength, mission, and object type
Between the columns AND Between the rows
OR In this example one wants to find galaxies
observed in the infrared with the IRAS
satellite. Click on Find Catalogues to display
the results.
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Search by wavelength, mission, and object type
The result is a list of catalogues that can
be queried. You can select one or more of the
catalogues by clicking on the box at the
beginning of each row. Then click on Query
selected Tables.
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Find data of your favorite object
Type your favorite object name or position in the
field Target Name or Position. The name will be
resolved by Simbad that returns a position. A
cone search is made centered on this position
with a user specified radius. To display the
results, click on Find Data.
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Find data of your favorite object
Since we did not specify a catalogue, VizieR
searches in all available catalogues and displays
the results in a html format. Other formats can
be chosen.
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Find a catalogue by word matching
In this example one is looking for the IRAS
catalogue of Rice et al. Click on Find
Catalogues
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Find a catalogue by word matching
The list of available catalogues is
displayed. You can chose one or more of them by
clicking on the white boxes at the beginning of
each row. Click on Query selected Tables to
display the results.
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Query of several catalogues
If you want to query two or more catalogues, type
their names separated by a comma in the field
Direct access to Catalogues. Click then on
Find Catalogue.
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Query of several catalogues
The list of available catalogues is displayed. We
want to chose the IRAS catalogue of Point Sources
and the Virgo Cluster Catalogue (VCC).
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Catalogue Query with constraints
It is possible to search a catalogue with
constraints on one, several or all columns. For a
detailed description of the possibilities click
on Constraints. In this example we serach for
sources whose names begin with 0000, with a 12um
flux 0.5 Jy, a 25um flux between 0.3 and 0.6
Jy, and a 60mu flux between 0.3 and 0.8
Jy. Click on Submit Query to display the result.
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Catalogue Query with constraints
The result is displayed in a html format.
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Different output format
You can also save the result into a local
file. In this example we have chosen a
-separated format that can be easily read with
e.g. SQL. Click on ReSubmit to save the file.
Rename the file.
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Query using a list of targets
Now we want to extract a list of VCC sources from
the VCC catalogue.
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Query using a list of targets
We chose the VCC catalogue directly and click on
Find Catalogue.
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Query using a list of targets
Two catalogues are available. We chose the Virgo
Cluster catalogue.
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Query using a list of targets
VizieR resolves the names via Simbad who returns
a position for each object. The targets are
then searched within a cone centered on these
positions with a given radius. We chose a radius
of 1 arcmin. We only want one source per
target, i.e. the required VCC source. The result
shall be saved in a -separated format. To load
the list of targets, click on LIST of Targets.
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Query using a list of targets
Search for your local file (Browse) and click
on the Results only button. Click on Submit
Query to save the result as a file. Rename
the file (here vcc.dat).
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Query using a list of targets
The output file contains all required information
on the sources. Comment lines begin with a .
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Query using a list of targets
We want to investigate if these VCC sources have
counterparts in the IRAS point source
catalogue. Therefore, we chose IRAS on the
VizieR main page and click on Find Catalogue.
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Query using a list of targets
We chose the IRAS point source catalogue and
click on Query selected Catalogues.
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Query using a list of targets
As before, VizieR makes a cone search centered
on the source positions (contained in the
vcc.dat file) and a given radius. We chose a
radius of 1 arcmin and only want the IRAS
sources corresponding to the VCC source.
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Query using a list of targets
We now have to load the VCC source file vcc.dat
by clicking on List of Targets and loading the
local file (Browse). Click on Submit Query to
display the results.
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Query using a list of targets
Here we have asked an html output format. Only
one VCC source has an IRAS point source
counterpart.