DIVA+ documentation

The DIVA+ archive allows you to search for and download data that has been processed in our service. These reduced data products can also be directly downloaded via our client. However, the search functionality of the client differs significantly from that of DIVA+, which offers a more user-friendly experience if you are primarily interested in reduced data. With DIVA+, you can filter data using more detailed criteria, such as detection characteristics, stellar companions, solar system object observations, and more. Additionally, DIVA+ provides the reduced data in HCI-FITS format. In the near future (2024-2025), you will also be able to download, in a single archive, reduced data from both SPHERE-DC and other surveys.

Please be advised that several features will be improved shortly. These features are marked with a WARNING in this documentation.

Available surveys in DIVA+

In DIVA+, we offer reduced products [including detection limits, signal-to-noise ratio (SNR) maps, and characterization (astrometry + photometry) of the detections] from High Contrast Imaging surveys and SPHERE public reduced data. Should you require raw data, please reach out to the Principal Investigator of the surveys, or the ESO archive for SPHERE data. For those interested in reprocessing SPHERE data, the necessary tools are detailed on the Data Processing Center page.

WARNING: The Surveys page show the available surveys in DIVA+. The DIVA+ search tool (allowing to access individual reduction products) can currently be used on only a limited number of surveys (first table of the surveys page). The other surveys can be downloaded by clicking on “Archive” in the DIVA table (the second table on the surveys page). However, it is not yet possible to search within these surveys: We plan to integrate these surveys into DIVA+ in the upcoming months.

To retrieve data from DIVA+, follow these three steps:

  • 1) Utilize one of the search menus (located at the top of the site)
  • 2) Select the output columns (accessible via the button in the top banner of the Dataset search menu)
  • 3) Proceed to the result table (accessible via the button in the top banner of the Dataset search menu)

The most suitable output columns are preselected for each specific search menu. Therefore, you can directly proceed to the result table once you’ve completed the search menu. However, if necessary, you can select additional information to be included in the result table through the output columns menu.

The search menus, output columns, and result table are described in detail below. For instructions on how to query the DIVA+ database using your own APIs, please refer to the APIs query menu section of the DIVA+ documentation.

I- Search menus

In order to access quickly different types of reduced data, we have created several “views” accessible through three sub-menues of the search menu. Two basic queries are proposed (for stellar objects and solar system objects respectively) in the first panel of the Quick search menus. More sophisticated queries can be performed, either by considering the list of additional query parameters in these two menus, or by goind to the Advanced search menu. We detail here these three menus:

  • 1) Quick search reductions of star observations

The quick search reductions of star observations should be sufficient for most of the users who want to download high contrast imaging reduced data. You can quickly search reductions with a list of star names, instruments, survey names and range of observing dates. By expanding the submenus at the bottom of this page, you will gain access to many other search criteria described below in “Advanced Search.”

The field on the left-side, by default setted to “in”, indicates that you are selecting observations including the indicated parameters (for example a given star or data range). The NULL and NOT NULL options are described at the end of this documentation. They have been deactivated because they are not particularly useful, but they can be reactivated for specific fields if needed. Please contact us if you require assistance.

  • 2) Quick search reductions of solar system object observations

The quick search reduction of solar system object must be used only for solar system object (planets, asteroids, comets, etc.). You will not find these reductions of solar system objects in the first menu (Quick search reductions of stars observations). By expanding the submenus at the bottom of this page, you will gain access to many other search criteria described below in “Advanced Search.”

  • 3) Advanced search

The Advanced search menu contains three search themes:

  • SEARCH REDUCTIONS OF STELLAR OBSERVATIONS
  • SEARCH REDUCTIONS OF SOLAR SYSTEM OBJECTS
  • COMPLEMENTARY SEARCHES

The SEARCH REDUCTION OF STELLAR OBSERVATION theme contains the Quick Search Reductions of stars observations menu, and the SEARCH REDUCTIONS OF SOLAR SYSTEM OBJECT theme contains the Quick Search Reductions of solar system objects menu, already described above. However, these themes also allow you to search the database in many other ways: For example, you can directly access the table of the characterization of detections (astrometry + photometry) via the Detections characterisations menu, or the Star table (containing the stars known to DIVA+ and many informations on these stars) via the Star menu. Here is a description of the advanced search menu:

Search reductions of stellar observation

Quick search reductions of star observations  gathers all the reduced observations on stars. Each reduction is composed of one or several images (several broadband images or an IFU cube) and may identify one or several detections in the image set. You can refine your search for reductions using a wide array of criteria:

  • General Information: such as star name, instrument, observation date, and survey name.

WARNING: When searching for a star name, you can use one of the Simbad names, which will be mapped to the corresponding DIVA+ name. However, for now, the result table will display only the DIVA+ name. In a future release, we will update ANIS so that the star name you used will be preserved in the result table after it has been resolved.

  • Observation Information: including telescope, instrument setup or mode, coronagraph type, range of Julian days, exposure time, pixel scale, visibility of disk, and in the near future DOI.
  • Wavelength Information: specifying the start and end wavelengths of the image set composing the reduction.
  • Reduction Information: details about the algorithm used for the reduction, the number of modes for PCA algorithms, and the number of detections in the reduction.
  • Star Information: covers a range of spectral type, mass, radius, age, effective temperature (teff), surface gravity (log g), metallicity, UBVRIHK magnitudes.
  • Internal DIVA+ Reduction Identifier: for specific searches within the DIVA+ system.

Detections characterisations allow to access list of the characterisation (astrometry and photometry) of the object detections in the individual images composing the reduced observations. This menu can be used for exemple to prepare a csv file for use with the Orbitize python module (see also How to query DIVA+ through your APIs). You can refine your search for detection characterisations using a wide array of criteria:

  • By object information: star name (Searches can be made using one of the Simbad name, which will be mapped to the corresponding DIVA+ name), and by companion letter (ex: b, c, d, e, etc.).
  • Observation Information: including instrument, instrument setup, range of date and Julian days.
  • Reduction Information: details about the algorithm used for the reduction, and the number of modes for PCA algorithms
  • Characterisation information: separation, position angle ranges, dmag ranges, sns ranges, polarization degree ranges
  • Image information: band (H, K1k2, etc.), ranges of the central wavelength of the image, ranges of the image polarisation angles in which you would like to retrieved the detections characterizations.

Stars section encompasses all stars recognized by DIVA+. You can refine your search within the star dataset by employing a wide array of criteria:

  • Main criteria: Star name (Searches can be made using one of the Simbad name, which will be mapped to the corresponding DIVA+ name), Spectral type of the star
  • Complementary criteria: Range of star distance, mass, radius, metallicity, ages, Effective Temperature (Teff), Surface Gravity (log g)
  • Magnitudes: Magnitude Range in UBVRIJHK

Star Companions gathers the identified companions. You can refine your search within the star companions dataset by employing criteria:

  • Main criteria: Star name (Searches can be made using one of the Simbad name, which will be mapped to the corresponding DIVA+ name), Common name of the companion (for instance beta pic b), type of companion (planet or Brown dwarf)

When we import the characterization tables into DIVA+, the companions are usually not identified. We progressively perform this task using the check_companions script (refer to the DIVA+ API documentation for more details). Subsequently, we cross-reference these companions in scientific articles.

But, some detections in the database are not flagged as companions for various reasons: a low signal-to-noise ratio (SNR), the absence of corroborating publications in the bibliography to confirm their status as companions, or a lack of time to conduct the identification work. If you are interested in a specific companion, we highly recommend using the check_companions.py Jupyter notebook. This tool verifies the presence of companions in the DIVA+ detections table based on their positions as described by known orbits. It is then incumbent upon you to conduct further verifications (e.g., photometric analysis) to confirm that the companions identified by this software are indeed the ones you are investigating.

Contact us if you need some help to identify companions in the DIVA+ detection tables.

Search reductions of solar system object observations

Reduced solar system object observations menu gathers reduced observations of solar system objects. You can refine your search for reductions using a wide array of criteria:

  • General Information: such as star name (Searches can be made using the Simbad name, which will be mapped to the corresponding DIVA+ name), object type, instrument, observation date, and survey name.
  • Observation Information: including telescope, instrument setup or mode, coronagraph type, range of Julian days, exposure time, pixel scale, and in the near future DOI.
  • Wavelength Information: specifying the start and end wavelengths of the image set composing the reduction.
  • Reduction informations: details about the algorithm used for the reduction, the number of modes for PCA algorithms
  • Internal DIVA+ object identifier: for specific searches within the DIVA+ system.
complementary Searches

Detections in the reduced stellar observations  correspond to all potential companion candidates detected in the image on a subsample of the reduced data. Those detections are not necessarily planets or more generally companions, but can also be background star or galaxies for example. We recall that because this processing step is not fully automatized, it has not been applied to all data. You have the ability to refine your search for detections utilizing a comprehensive set of criteria:

  • Object information: Star name (Searches can be made using one of the Simbad names, which will be mapped to the corresponding DIVA+ name), Companion letter (e.g., b, c, d, etc.), Object common name (for instance beta pic b), Status of the detection being searched for (Unknown, Ambiguous, Background, or Companion)
  • Detection Information: Wavelength Range, Contrast (Δmag), Angular Separation, Position Angle, ΔRA, and ΔDEC
  • Reduction and observation information: Telescope, Instrument name, Instrument setup and mode, Coronagraph type, Range of classical observation date, MJD observation date, exposure time. Survey name, Algorithm used for the reduction, the number of modes for PCA algorithms.
  • Internal DIVA+ object identifier: for specific searches within the DIVA+ system.

Individual reduced images allow to access quickly a list of individual images (or cube slices) composing the reduced observations. The reductions of star observations allows to get all the products of one reduction (cube of images, cube of SNR maps, astrometry of the detections at all the wavelenghts, etc.) in one file (HCI-FITS and/or tgz) while Individual reduced images allows to download only one reduced image or detection limit by lambda.

Dates in diva+

Fields that use a date in DIVA+ utilize the module described here: https://valor-software.com/ngx-bootstrap/#/components/datepicker?tab=overview

This datepicker module provides a user-friendly interface for selecting dates, with options for setting the format, minimum and maximum date.

To change the year in the graphical interface, simply click on the year displayed. After selecting a range of dates using the graphical interface, you can also modify them manually. It may be easier to enter two very distant dates (e.g., 2015-02-01 – 2024-01-01) to quickly set a wide range of years, and then adjust the start and end dates as needed.

II-output columns

In this menu, you can select or deselect output options that you would like to include in the final result table. Most of the available output options are self-explanatory. In this section, we provide explanations only for the output options that require additional clarification.

Observation information

reduction_target_name (default: not selected): This name may differ from the star_name . For example, several stars in binary systems (e.g., HIP16563B) do not have a Simbad name. In such cases, the star_name will be listed as HIP16563 (the Simbad name), while the reduction_target_name will be listed as HIP16563B.

Star information
Associated files 

The full_reduction_file option allows you to obtain all the products (REDUCED_DATA, SNR_MAP, SENSITIVITY_MAP, DETECTION_LIMIT, SOURCE_DETECTION) from a single HCI reduction in one comprehensive HCI-FITS file, as described here.

You can read the DIVA+ HCIFITS files with this script or with this class.

III-Result table (download data)

You have the option to download the result table in various formats, including JSON, ASCII, and CSV. If you wish to download only specific rows from the result table, please ensure to select those rows prior to clicking on the ‘Download Result Table’ links (available in JSON, ASCII, and CSV formats).

To download the reduced data (HCIFITS) for the selected reductions, click on ‘Archive’. If no rows are selected in the Result table, all reductions will be downloaded.

WARNING: The reduced data in DIVA+ is formatted in HCIFITS. A CLASS has been developed and is available on GitHub to assist you in manipulating these files.

WARNING: Please note that creating a large archive (e.g., the entire SHINE survey) can take some time. In such cases, we strongly recommend creating a DIVA+ account by clicking on ‘Sign In / Register’ at the top right of the page. If you click on ‘Archive’ while logged in, you can exit the DIVA+ web page while your archive is being prepared. You will receive an email notification when your archive is ready to download. You can then download your archive from your Register account by clicking on the top right icon indicating that you are logged in, and then selecting ‘Archive list’.

IV – Technical description

The technical documentation for DIVA+, including the data model and table relationships, can be downloaded here: