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Table of Contents:
Target Information Archival Information Ambient Parameters
Observing Program and Scheduling Observation Block Additional Tools
Data Product Information Instrumental Setup Display Options
The following sections provide some help on how to use and what to enter for the various query parameters offered in the Main ESO Archive query form. Access is supplied through the WDB interface. If this is the first time you use this system, we recommend that you read the short WDB help page on how to specify queries and use operators to make full use of this system.
Target Information
This section provides information on the query parameters used to find observations of specific named objects or centered on specified RA and DEC coordinates.
Target Name Specify the name of the astronomical object you want to search for and select the appropriate name resolver from the pull-down menu. Target identifiers may be resolved into coordinates by Simbad (default), NED, or matched against the OBJECT keyword value as specified in the data FITS header.

NED is an extragalactic database, hence galactic targets should be resolved by SIMBAD.

If you match the target name against the OBJECT FITS keyword value, it will be wildcarded and the search will be case insensitive: car might return eta car, Cartwheel,... To change this default behaviour, use the following operands:

  • =car* will match carina,... but not eta car nor Carina.
  • ~car* will match carina, Carina, Cartwheel,... but not eta car.
  • ==carina will match exactly.

Solar System bodies cannot be resolved. Thus, if you would like to search for moving targets, enter a target name (e.g. neptune) and do not select any name resolver but instead choose the option 'OBJECT - FITS keyword' from the pull-down menu.

 

OBS Target Name The target name as defined by the Principal Investigator (PI) during Phase 2.
OBJECT It is either the target designation (as given by the astronomer) for science exposures or the exposure Type for non-science frames.
Search Box If you search by coordinates or target name, enter here the size of the search box around the target.
Alternatively, if you search by range in RA and DEC (see below), the Search Box field must be empty.
RA Alternatively to the target name, you can specify here the Right Ascension. Recognised format is either sexagesimal or decimal hours.
For sexagesimal notation, both blanks and colons are accepted as separators between hours, minutes and seconds.
You may also search by range in RA (e.g. 15:00 .. 15:30). If so, be sure to empty the Search Box field.
DEC Alternatively to the target name, you can specify here the Declination. Recognised format is either sexagesimal or decimal degrees.
For sexagesimal notation, both blanks and colons are accepted as separators between degrees, arcminutes and arcseconds.
You may also search by range in DEC (e.g. -51 00 .. -50 00). If so, be sure to empty the Search Box field.
Input Format Use the pull-down menu to indicate wether input values for RA are given in hours or degrees.
List of Targets Suppose you have a list of targets and you would like to query the ESO Archive for each target in that list. Instead of having to re-type the target name or coordinates and run a new search for each target in the list, you may query the ESO Archive using an input file of targets. Click on the 'Browse' button to locate and upload the file from your local directories. The file must contain no more than one target per line. The target can be
  • either a Name
  • or a set of RA and DEC coordinates being Tab-separated

A few notes regarding the syntax of the input file:

  • Lines starting with a single hash '#' are not recognized as targets, but they will be displayed on the query result screen as comments.
  • Comments may contain HTML tags.
  • You may add your own input notes or comments as an additional column in the query results. Simply add a hash '#' after the target, followed by your input comments. Here are some examples:
    • HD 93308 # Variable Star
    • 10 45 03.591 \tab -59 41 04.26 # eta car
    The strings Variable Star and eta car will then get added to the query results in the first column, named Note. It is useful for further processing of the query results, especially with formatted results like TSV or VOTable.
  • Blank lines are ignored, as well as lines starting with a double hash '##'.
In addition, choose the appropriate name resolver from the pull-down menu. A database search will be performed for each target in the uploaded list. If one of the target names cannot be resolved, it is skipped and the search proceeds with the next target in the list.
Do not forget to set the size of the Search Box and the Output Format for coordinates!

 

Output Format Choose here the output format for coordinates: either sexagesimal hours or decimal degrees/hours.
Mark the checkbox to display the coordinates on the query result page. Coordinates are displayed in the field labelled Target Ra, Dec.
Galactic Search Box If you search by galactic coordinates, enter here the size of the search box around the target.
Galactic Longitude Search position in galactic longitude. If a precise value is given, then a boxsearch with the size given in the Galactic Search box field is executed. It is also possible to specify ranges or regions with the .., the < and the > operators. Note that values for the galactic longitudes range from 0 to 360 degrees.
Examples: 100..150 or >200
Galactic Latitude Search position in galactic latitude. If a precise value is given, then a boxsearch with the size given in the Galactic Search box field is executed. It is also possible to specify ranges or regions with the .., the < and the > operators. Note that values for the galactic longitudes range from -90 to 90 degrees.
Examples: -60..-40 or <10
Observing Program Information and Scheduling Parameters
This section provides information on the query parameters used to find observations carried out during specific nights or in a specific program.
Night Enter here the date of the beginning of the night in YYYY MM(M) DD (or DD MM(M) YYYY also acceptable)
or specify a range of nights in the Start and End fields.
An ESO night starts at noon and finishes at noon the following day.
Start Enter the date of the first night in YYYY MM(M) DD (or DD MM(M) YYYY also acceptable) and select a time from the pull-down menu.
End Enter the date of the last night in YYYY MM(M) DD (or DD MM(M) YYYY also acceptable) and select a time from the pull-down menu.
Program ID Read the documentation on the ESO programme identification code.
Program Type

 

PI and CoIs Enter here the name of the Principal or Co-Investigator.
You may specify multiple names with the help of the OR operand, e.g. Smith OR Dupont.
Service/Visitor Mode Choose Service or Visitor mode from the pull-down menu.
Title of the proposal Enter here words from the title of the proposal.
You may specify multiple words with the help of the OR operand, e.g. galaxy OR massive.
Data Product Information
This section provides information on the query parameters related to a data product and its content. Parameters Category, Type and Mode provide unique high level description of an observation in terms of its purpose and technique. Note that only certain combinations of these keyword values are meaningful.
Category Choose the observation Category from the list. Multiple choices are allowed.

SCIENCE Any scientific object
CALIB Any calibration source
ACQUISITION Any scientific object
TECHNICAL Any exposure taken to verify instrument performance/setup
TEST Any exposure taken to test instrument performance/setup/software/conditions
SIMULATION Any simulated exposure
OTHER Any other exposure

 

Type Choose here the type of observation/exposure.

A pull-down menu lists commonly used Type values. It is not intended as a complete list of allowed values. Instead, it is intended as guidelines showing what type of information is included in those parameters.

Alternatively, user defined input may be given in the text field below the pull-down menu.
Indeed, the Type can take more than one value. The values are separated with commas, without any blank spaces. This provides the means to describe a wide range of observations. If more than one value is present, it generally follows the general-to-specific order, i.e. a general term describing the type of technique, followed by qualifiers describing more specific details: e.g. FLAT,LAMP or FLAT,SKY. However, note that some observations are tagged the other way around: e.g. LAMP,FLAT or SKY,FLAT.

Principal values and qualifiers are listed below. More details are available from the ESO data interface web page.

Principal Values:
OBJECT Any observation of an unspecified object
STD Any observation of a standard calibration source
ASTROMETRY Astrometric standard field
BIAS Readout frame
DARK Dark exposure (shutter closed)
FLAT Any flat field exposure
Qualifiers:
SKY Any observation of an empty field on the sky
LAMP Any lamp exposure
DOME Any exposure using the dome
SCREEN Any exposure using an illuminated screen
FLUX Flux standard (spectroscopy and photometry)
PSF-CALIBRATOR Reference star for PSF calibration
WAVE Any (instrument-internal) wavelength calibration
FOCUS Any focus exposure
SLIT Any non-spectroscopic exposure using a slit
FIBER Any exposure using fibers
BEAM_<x> Any observation in interferometry using only one beam (x=A, B)
FMTCHK Any arc-lamp exposure to obtain forst-order guesses for dispersion sol. (UVES)
ORDERDEF Any flat-field exposure to derive order and background positions (UVES)
OzPoz Exposures taken using the Fibre Positioner (FLAMES)
... ...

 

Mode The Mode is the technique used for the observation.

This field is to be used in the following cases:
  • You did select one or more instruments from the available lists of Imagers/Spectrographs/VLTI, and you would like to give more precise constraints on the Mode than the default ones which appear in the text field Instrument & Mode once you select an instrument.
    Example - Suppose you want to search for VIMOS SCIENCE observations in IFU mode:
    • Mark the VIMOS checkbox in the list of available spectrographs. It will add some constraints to your query in the field labeled Instrument & Mode:
      ((ins_id like 'VIMOS%' AND ((dp_tech like 'IFU%' OR dp_tech like 'MOS%') OR (dp_cat != 'SCIENCE'))))
    • Edit it as follows: ((ins_id like 'VIMOS%'))
    • Select IFU from the Mode pull-down menu and mark the SCIENCE checkbox in the list of Categories.
    • Submit!
  • You did not select any instrument from the available lists of Imagers/Spectrographs/VLTI, but you would like to query by Mode anyway.

The pull-down menu lists commonly used Mode values. It is not intended as a complete list of allowed values. Instead, it is intended as guidelines showing what type of information is included in those parameters.

Alternatively, user defined input may be given in the text field below the pull-down menu.
Indeed, the Mode can take more than one value. The values are separated with commas, without any blank spaces. This provides the means to describe a wide range of observations. If more than one value is present, it follows the general-to-specific order, i.e. a general term describing the type of technique, followed by qualifiers describing more specific details. For instance, a jittered NACO polarimetry observation with the Wollaston prism would be described as POLARIMETRY,WOLLASTON,JITTER.

Principal values and qualifiers are listed below. More details are available from the ESO data interface web page.

Principal Values:
IMAGE Any picture
SPECTRUM Single-order spectrum
ECHELLE Cross-dispersed spectrum
MOS Frame with spectra of several objects
MXU Frame with spectra of several objects using a pre-manufactured mask
IFU Integral Field Unit observation
POLARIMETRY Polarimetric exposure
CORONOGRAPHY Coronographic exposure
INTERFEROMETRY Coherent exposure with more than one telescope beam
Qualifiers:
TEL-THROUGH Telescope through-focus sequence
INS-THROUGH Instrument through-focus sequence
WEDGE Focus wedge frame
HARTMANN Hartmann focus test
ABSORPTION-CELL Absorption lines included (e.g. Iodine cell)
DRIFTSCAN Drift scanning exposure
WOLLASTON Wollaston polarimetry
WIRE_GRID Wire grid polarimetry
DIRECT Qualifier indicating direct imaging/spectroscopy
CHOPPING Exposure utilising M2 chopping
NODDING Exposure utilising telescope nodding
CHOPNOD Exposure utilising both chopping and nodding
JITTER Exposure utilising source jittering technique
SLIC#<i> Observation using image slicer #i (UVES)
HIT High time resolution mode (FORS)
FILTERCURVE Spectroscopic flatfield with a narrowband filter included (FORS)
SPIDER Exposure using SkySpider (SINFONI)
... ...

 

Instrument & Mode Instruments are splitted into several modes: imaging, spectroscopy, interferometry, polarimetry, coronography and other.
If you mark one or more instrument checkboxes, constraints both on the instrument ID (ins_id) and the Mode (dp_tech) will be automatically added to your query.
Those constraints are editable in the text field labeled Instrument & Mode.
Additional user defined constraints may be given in that field, provided you follow the SQL-like format.
Archival Information
Dataset ID The Dataset ID is the name under which the data product is stored in the ESO Archive.
This unique identifier consists of an instrument prefix followed by a timestamp (e.g. INS.YYYY-MM-DDTHH:MM:SS.sss).
To learn more about the instrument prefix, please visit our FAQ.
The Dataset ID corresponds to the FITS keyword ARCFILE, without the extension.
Orig Name The original file name as used on the instrument workstation at the telescope.
Release Date Except for a few special cases, there is a one year proprietary period for the PI regarding SCIENCE and ACQUISITION frames. Once the proprietary period has expired, data are released.
Frames belonging to all the other Categories, such as CALIB, are immediately public.
  • 25 07 2005 .. 26 07 2005 will retrieve frames with a release date set to July 25th 2005.
  • > 25 07 2005 will retrieve frames with a release date greater than or equal to July 25th 2005.
MJD-OBS (Toggle mode) - MJD-OBS is the modified Julian Date (JD - 2400000.5) of the start of the observation.
Observation Information
This section provides information on the query parameters used to find observations carried out with certain constraints as specified in the Observation Block.
OB Name Enter the name of the Observation Block itself, if known.
OB ID Enter the OB Identification here, if known. It should be a unique numeric ID, assigned to the Observation Block by the Observation Handling System.
OB TPLNO It provides the template sequence number within the Observation Block.
TPL ID The identifier (name) of an observing template (observing template: entity containing a sequencer script, dealing with the setup and execution of one or more exposures of a particular type)
TPL START The start date marks the time when the observing template was executed.
TPL NEXP The number of exposures expected within the given observing template.
TPL EXPNO It provides the exposure number within the VLT observing template.
Instrumental Setup
This section provides information on the query parameters used to find observations according to instrumental setup.
Exptime The exposure time, in seconds. For infrared instruments the definition of exposure time is different in different contexts.
  • Within a instrument-specific query form (except VIRCAM) the Exptime corresponds to the averaged exposure time. This is because the counts of a single raw frame are averaged over a number (NDIT) of exposures, hence the EXPTIME FITS keyword, and consequently the Exptime value in the query form, corresponds to the value of the DIT keyword in the FITS header.
  • Within the main raw query form it corresponds to the total integration time (DIT * NDIT). For VIRCAM, the EXPTIME is always (i.e. in all contexts) defined to be the total integration time.
For all other (non-infrared) instruments, the exposure time corresponds to the total integration time.

For LABOCA, the exposure time may be underestimated due to the continuous data taking setup, which records only exptime of the first subscan.

Note that there is an known issue on the main raw query form, when querying for an infrared instrument (except VIRCAM): while the total integration time is shown in the result page, in input (when the user places a constraint on the Exptime field) the user's condition is applied to the averaged exposure time instead. This behaviour will be corrected soon.

Chip ID (No query, full-screen mode) - Detector chip identification.
Exp ID (No query, full-screen mode) - Unique exposure ID number.
Filter All filters.
This string is in the format <value>,<value>,...
where <value> is the value of one of the FITS keywords INS.FILT*.NAME.
Example: SK,open
Grism All grisms.
This string is in the format <value>,<value>,...
where <value> is the value of one of the FITS keywords INS.GRIS*.NAME.
Example: GRIS_600B
Grating All gratings.
This string is in the format <value>,<value>,...
where <value> is the value of one of the FITS keywords INS.GRAT*.NAME.
Slit All slits.
This string is in the format <value>,<value>,...
where <value> is the value of one of the FITS keywords INS.SLIT*.NAME.
NX (No query, full-screen mode) - Number of pixels along X axis.
NY (No query, full-screen mode) - Number of pixels along Y axis.
Ambient Parameters
This section provides information on the tools available to find out under which ambient conditions the observations were carried out.
DIMM-Seeing (Toggle mode) - The average FWHM seeing conditions calculated over the exposure time as measured by the DIMM station. The Seeing viewer can be invoked by clicking on the 'DIMM Seeing?' link in the 'Ambient' column of the query result page. Other ambient conditions such as humidity, temperature, pressure, wind speed etc can be obtained from the ESO Ambient Conditions Database Server.
Airmass (Toggle mode) - The airmass at the start of the observation.
Additional Tools
FITS Header Display (Toggle mode) - The ESO Archive stores on-line the complete FITS headers of all raw FITS files. The FITS header viewer can be invoked by clicking on the 'Header' link in the 'HDR' column of the query result page.
FITS Preview (Toggle mode) - Previews for the WFI instrument at the 2.2m telescope in La Silla are now available through the main ESO Archive query form for the year 2005. More WFI previews from previous years will be posted in the following weeks. Previews come in JPG and H-compress FITS format ('PRV' column of the query result page). They are obtained by processing raw WFI frames (already in the public domain) with ESO-MVM in an automated fashion. An approximate bias subtraction and flat fielding is applied to the raw frames using master calibrations obtained once a month. A rough de-fringing for the I- and z-band exposures is applied building fringing maps from science frames taken over several nights, as in-night widely dithered science frames are not available for most of these observations. As a result, the fringing correction is often not satisfactory. The resulting images are then rebinned by a factor of 10 and compressed using a loss-less algorithm. To uncompress those files, one can for example apply the standard CFITSIO program:
imcopy 'file.hfits[1]' file.fits
FITS images contain astrometry (WCS) information with an accuracy of ~1 arcsec.
Preview availability and time coverage:
   1999       2000       2001       2002       2003       2004       2005       2006   
100%
100%
100%
100%
 
Remark: for the periods of preview availability (blue colour) highlighted in the table above, please note that some previews could not be processed because either the observed images were blank, or the observations were not completed, or some chip(s) were missing.
Distance (Toggle mode) - For each source matching your request, the computed distance (in degrees) from the input target will be displayed in an extra column in the query result page. A target is defined either as the name of an astronomical object (e.g. 4C-00.62) or as a set of coordinates (RA=15:00 ; DEC=-51:00). Note that user defined ranges in RA/DEC do not define a target.
Position Angle (Toggle mode) - The position angle of the retrieved observation as seen from the input target (see "Distance" above) from North to East anticlockwise.
Number of Frames (Toggle mode) - Mark the checkbox to get the total number of frames returned by your query, on a per Instrument basis. Statistics will be displayed at the bottom of the query result page.
Cumulative Exptime (Toggle mode) - Mark the checkbox to get the cumulative Exptime per Filter, Instrument and Category. Statistics will be displayed at the bottom of the query result page.

Please note that the Cumulative Exposure Time is overestimated for multi-chip instruments (e.g. FORS2, VIMOS, XSHOOTER).

Sky Map (Toggle mode) - Mark the checkbox and the Aladin Java applet will provide you with the pointing distribution of all the sources matching your request and having Ra, Dec information. Just click on the Aladin logo at the bottom of the query result page. In addition, the Aladin image server will find the best background image to be loaded (MAMA, DSS2 or DSS1), provided the size of your search box is less than 6 degrees.

Each matching source displayed in Aladin is colour-coded by instrument and is linked back to the ESO Archive by clicking in the Aladin measurement window:

  • on the appropriate RequestData link to request the dataset file from the ESO Archive (you will be asked for your ESO User Portal credentials -- username and password -- to reach the Request Submission Setup)
  • on the appropriate Dataset ID (you will get full ESO Archive information for this record)
  • on the Program ID (you will get full observing program and scheduling information)
The interchange of data between ESO and Aladin is done via a VOTable, an XML standard for tabular data.
More about the VOTable description is available at http://www.ivoa.net/Documents/latest/VOT.html.
You may download the VOTable by right-clicking (Save Link Target as...) on the filename votableNUMBER.xml.
If the query results do not contain any Ra, Dec information, no VOTable is produced.
Display Options
Mark To request data please select the datasets in the results table by marking the checkbox in the left-most column, then press the button labeled Request Marked Datasets. Datasets for which the proprietary period is over are highlighted in green and are publicly available. Datasets that are still under the proprietary period are highlighted in red and can only be downloaded by the corresponding PI.
- More If you are in tabular mode and you wish to display the full individual record of a matching source, click on the appropriate magnifying glass in the query result page.
Default Mode (Toggle mode) - By default, if more than one record is retrieved, results will be displayed in tabular mode, one matching record per line. If only one record is retrieved, it is displayed in full-screen mode.
VOTable Mode (Toggle mode) - The VOTable format is a Virtual Observatory standard.
Tabular Mode (Toggle mode) - If more than one record is retrieved, or if you mark this checkbox, results will be displayed in HTML tabular format, one matching record per line.
Full-Screen Mode (Toggle mode) - If only one record is retrieved, or if you mark this checkbox, the results of your query will give you the full individual record display, regardless of the selected toggle parameters on the query page.
Export File (Toggle mode) - To export the results of your query to an ascii file, mark the checkbox and select the field separator from the pull-down menu.
The Export File option requires the tabular mode to be turned on.
If you are in Export File mode, hyperlinks towards external databases (e.g. Program ID) will be turned off in the HTML result table.
Currently available export formats are:
  • Tab-Separated-Values (TSV format)
  • |-Separated-Values
  • Comma-Separated-Values
The following sentence will display at the bottom of the query result page:

Download query results from: exportNUMBER (format)

To download the export file, right-click (Save Link Target as...) on exportNUMBER.









































 
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