The ESO Archive Community Forum is a platform for sharing ideas and methods, asking questions and sending feedback and suggestions on how to improve and use the new ESO Archive Science Portal and on how to  gain Programmatic and tool access to the archive science portal. 

Contributions from all users are encouraged, also without registration.

To participate in the knowledge exchange, please choose an appropriate Forum from the right panel or from the drop-down menu on the top of this page and write a message. An agent from the ESO Archive Science Group (ASG) will receive, moderated it, and make it public as soon as possible.

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The ESO Archive Community Forum also provides help pages about the data access and retrieval, and about the data types used in the ESO Archive.

Please be aware that the channel to receive help concerning data access, data reduction and pipelines, and quality of products is provided by the ESO helpdesk.

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HARPS - How to get the pipeline generated files (CCF, s1d, e2ds, bis, INT_GUIDE)

Archive Science Group 1 year ago 0

The HARPS pipeline generates separate products for both HARPS fibres (labelled A and B), cross correlating the observed spectra with template stellar spectra for various spectral types.

The primary product is a rebinned, combined 1-D spectrum in FITS binary spectroscopic data format. It is accompanied by a TAR file, containing the products of the original pipeline processing, both FITS and non-FITS.

Their content can be identified from their filenames. The root file name is “HARPS.<date_obs>”, where <date_obs> is the start of the observation in the “restricted ISO8601” format. This root name is appended with:

• “_s1d_<fibre>.fits” for 1-D extracted full spectrum, wavelength calibrated, in the solar system barycentric frame (the primary file of the release is the fibre A s1d file converted to the binary table format);

• “_e2ds_<fiber>.fits” for 2-D extracted spectrum, one row per order;

• “_bis_<sptype>_<fiber>.fits” for bisector from the cross correlation computed with the <sptype> mask;

• “_ccf_<sptype>_<fiber>.fits” for cross correlation function matrix for mask for ;

• “_ccf_<sptype>_<fiber>.tbl” for cross correlation function summary table (ASCII) with extracted radial velocity per each order;

• “_INT_GUIDE.fits” for integrated guiding image from the guide camera, used to confirm the correct centering of the star on the fibre. The image is integrated over the whole length of the scientific exposure.


• <fiber> is either “A” or “B”; in science observations the A fibre is used for the object, while the B fibre is used for ThAr lamp, dark or sky exposure, depending on the observation setup.

• <sptype> is either one of “G2”, “K5” or “M2”, depending on which spectral mask was used in cross-correlation with the spectrum. The pipeline automatically selects one of the masks based on the object’s spectral type, as recorded in the “HIERARCH ESO DPR TYPE” keyword. The “G2” mask is used if the spectral type is G9 or earlier or no spectral type is recorded, the “K5” mask is used for all Kn spectral types, and the “M2” mask is used for spectral types of M0 or later.


How can I get the CCF file? - edited

Anonymous 1 year ago updated by Archive Science Group 1 year ago 1

edited message -- I need the CCF file for radial velocity correction?

original message

How can I get the ccv file? 

I need the ccv file for radial velocity correction?

Under review

How can a locate spatially the X-Shooter slit using the information presented in the header (in the "XS_SRE2" file)?

Bruno 2 years ago updated by Archive Science Group 2 years ago 1

I'm trying to locate the slit from an observation available in the data archive ("XS_SRE2" file). I am trying to compare it with integral field spectroscopy data from another instrument (creating a pseudo-slit). For this, I need to locate the X-Shooter slit in the sky.

- Should I use the keywords "CRVARL2", "CDELT2" as offsets (along the slit) from sky coordinate ("RA", "DEC")? In this case, the Position Angle (PA) should be equal to: PA = - "HIERARCH ESO ADA POSANG" (note the negative sign)?

- The XS_SRE2 file has 99 rows (in the sky offset dimension). It seems that the first 33, and the last 33 ones could be discarded, since they appear to be an effect of the Nod&Shuffle technique. Is that that right? This is the reason why there seems to be a contamination (fake aborption) in some rows in the middle (34 -- 66 rows, mainly the extreme ones 34-37 and 63-66)? Also, if I want to the offset in the sky (along the slit) of the row 35 (e.g.), it would be: OFFSET(35) = "CRVARL2" + 34 * "CDELT2"? 

- There is a way to convert the flux units from counts to physical units (e.g. erg/s/cm2/A)?

Thank you,


Second data release from the VISTA Cycle 2 ESO Public Survey VISIONS

Archive Science Group 2 years ago 0

Image 187

VISIONS (programme id 198.C-2009, PI J. Alves)

is a Near-Infrared ESO second cycle VISTA Public Survey which covers all major nearby star-forming regions accessible from the southern hemisphere. This imaging survey is designed to deliver deep high-sensitivity observations of areas with large amounts of extinction. It includes also control fields which sample the predominant stellar populations in largely extinction-free regions and multiple epochs imaging data over large areas surrounding the targeted star-forming regions to enable the computation of proper motions for sources inaccessible to Gaia.

This second data release (DR2) contains all the observations on the star-forming region Corona Australis. In total, 160 tiles covering about 43 deg2 have been observed, for a total of 3360 files and 0.87 T, between April 2017 and October 2021. The image quality is excellent throughout the entire survey fields with most data featuring point source FWHMs better than 1 arcsec. Compared to 2MASS, the survey reaches up to 6 mag fainter sensitivity limits.

For each observed field, photometrically and astrometrically calibrated tiles and stacked pawprints, together with a corresponding source table are published and available via the Archive Science Portal or programmatically.

A detailed description of the released data is available in the related documentation.


First data release of the Burst Alert Telescope AGN legacy survey of molecular gas fueling in powerful nearby AGN

Archive Science Group 2 years ago updated 2 years ago 0

The APEX telescope has obtained CO(2-1) spectra for a sample of 165 hard-X-Ray-selected AGN galaxies detected in observations by the Burst Alert Telescope (BAT) onboard Swift. These observations, taken under the ESO programme id 198.A-0708, PI M. Koss, allow a statistical comparison of AGN and non-AGN dominated

galaxies in the local Universe, for example from the ALLSMOG APEX survey.

Image 186

As this programme mainly aimed at observing a statistical sample of
nearby AGN, many of the galaxies observed are well-known galaxies, and these Phase 3 data can provide a valuable total power measurement of the CO(2-1) emission which then can be combined with interferometric observations obtained with ALMA.

Additionally, the BASS (BAT AGN Spectroscopic Survey) sample includes a variety of other ESO data products including hundreds of spectra with VLT/Xshooter, VLT/MUSE, and VLT/FORS2 with more information at the BASS survey website.

This BAT AGN release available via the Science Portal or programatically, makes the combined CO(2-1) spectra publicly available so users can derive further spectroscopic parameters, and compare them with other lines in these objects. The spectra either have a peak S/N>5 or reach depths of 0.5-2 mK rms for non-detections. Further details can be found in the data release paper or in the accompanying release description.

Instructions on how to read or display data in the ESO/SDP tabular data format can be found in the 1D spectrum data format help page.


First data release from the ESO VISTA Public Survey SHARKS - Southern H-ATLAS Regions in Ks-band

Archive Science Group 2 years ago updated 2 years ago 0

Image 183

The Southern H-ATLAS Regions in Ks-band (SHARKS) is a deep Ks-band imaging survey conducted with the wide-field VIRCAM imager at the VISTA telescope. The project was granted 1200 hours of observing time under the ESO programme 198.A-2006, PI H. Dannerbauer, as one of seven approved second cycle VISTA Public Surveys.

It covers ~300 deg2, including large parts of the South Galactic Plane (SGP), GAMA-12h (G12) and GAMA-15h (G15) fields from the H-ATLAS survey, the largest Herschel program. The survey has been designed to provide the best possible counterpart identification for ∼90% of the sources detected at 0 < z < 3 by H-ATLAS, ASKAP, SKA and LOFAR; to produce a sample of strong lenses for cosmography studies; to study the evolution of the most massive structures in the Universe.

SHARKS DR1 consists of calibrated images and single band source catalogues from observations taken between March 2017 and January 2019. It covers a sky area of about 20 deg2, divided in 10 mosaics of ~2 deg2 each. The 10 mosaics are distributed as follows: four contiguous mosaics in the SGP-E region, and two unrelated mosaics each in the SGP-W, G15 and G12 fields. The mean depth reaches the expected Ks magnitude of ~22.7 (AB, 5sigma) with a mean seeing of ~1’’. The products are available via the ESO Science Portal or programmatically. More information about the release is available in the related documentation.

SHARKS DR1 has been produced in collaboration with the Instituto de Astrofísica de Canarias (IAC) and the Wide-Field Astronomy Unit (WFAU) at the Royal Observatory of Edinburgh.


VVVX DR1.1 published: releasing the entire Ks time series

Archive Science Group 3 years ago 0


The VISTA Cycle 2 ESO Public Survey project -VVV eXtended- PI D. Minniti, P. Lucas, is carried out with VIRCAM on VISTA in the JHKs filters and covers a total of ~1540 deg2 of the southern Galactic plane.

The VVVX DR1.1 complements DR1 by mainly providing i) the missing Ks time series and ii) the source lists generated from the pawprints published in DR1, which were observed between July 2016 and March 2018. The released data total about 9 TB. Science products generated from observations in the time interval from April 2018 to October 2019 are accessible in the already published DR2 release.

The time series data were taken in 'THIN' conditions, thus data with photometric zero points within 0.25 mag of the seasonal average value are accepted. The rather relaxed requirement on the image quality (seeing < 2.0 arcsec) has proven useful to deliver photometry for the bright stars also, that otherwise are saturated in data acquired with better seeing conditions.

Data are available via the Archive Science Portal or programmatically.More information regarding the release content is available in the documentation.


New Gaia-ESO radia velocity catalogue released (DR4.1)

Archive Science Group 3 years ago 0


Gaia-ESO is a Public Spectroscopic Survey carried out with GIRAFFE and UVES on the VLT between 2012 and 2018. The survey targeted more than 100,000 stars, with 115,000 actually observed by the end of the survey. These stars are selected across all major components of the Milky Way, from halo to star-forming regions, with the goal of providing a homogeneous overview of their kinematics and elemental abundance distributions.

With DR4.1, the Gaia-ESO team publishes a catalogue of radial velocities of more than 110,000 stars, covering 97% of all the objects whose spectra were previously published in December 2020 (DR4). The catalogue releasing the parameters for all the observed stars and the remaining 1D stacked spectra for additional 600 unique targets will be published in the forthcoming DR5. The full description of the current published catalogue and of the pipeline used to determine radial velocities can be found in the detailed release document.

The catalogue preview (histograms and metadata) can be found here. An example of a programmatic access query to the catalogue is available here. The catalogue can be queried also via the Catalogue Facility.


Second data release from the VISTA Cycle 2 ESO Public Survey VVVX

Archive Science Group 3 years ago updated 3 years ago 0


The VISTA Cycle 2 ESO Public Survey project -VVV eXtended- PI D. Minniti, P. Lucas, is carried out with VIRCAM on VISTA in the JHKs filters and covers a total of ~1540 deg2 of the southern Galactic plane.

This second data release contains observations taken between April 2018 and October 2019. They consist of both multi-filter JHKs observations and time series Ks data with photometric limit reaching typically Ks=17.5 AB mag.

The survey data in Ks that were taken prior to April 2018 remain to be released (VVVX DR1 contained data from the multi-colour JHKs OBs and J-only OBs). The VVVX team is currently working to releasing these data as soon as possible, in order to provide a continuous time series.

Data are available via the ASP and programmatically: 10776 tile images plus their associated weight maps and single-band source catalogues. In addition, the release contains the 64716 pawprint images.

More details can be found in the release description.


Polygon search on dbo.raw

Mathieu VdS 3 years ago updated 3 years ago 6


When I perform an ADQL query on ivoa.ObsCore with a polygon search, I get the same results as with the graphical search tool (650 hits).

FROM ivoa.ObsCore
WHERE CONTAINS(POINT('J2000', s_ra, s_dec), POLYGON('J2000', 93.47786,-63.86,87.47072,-63.91703,88.3048,-62.10095,94.85457,-58.15919,97.7867,-61.61193))=1
AND instrument_name='GIRAFFE'

When I try to do the same query on dbo.raw or dbo.ssa, I obtain an error saying 'Latitude values must be between -90 and 90 degrees'.


FROM dbo.raw

WHERE CONTAINS(POINT('J2000', ra, dec), POLYGON('J2000', 93.47786,-63.86,87.47072,-63.91703,88.3048,-62.10095,94.85457,-58.15919,97.7867,-61.61193))=1

AND instrument='GIRAFFE'

Why is it happening? Is my second query fixable?

I used the graphical search tool to draw the polygon and know the RA, DEC couples defining it.

Thanks in advance

Archive Science Group 3 years ago


to avoid the error, please add the following constrain:

AND dec BETWEEN -90 and 90

in this way you get 7 files as result.

The reason is that the raw database is not as curate as the products one, we are going to look into this, thanks for reporting!