CHEOPS Data

Observations made with CHEOPS are available for download from the CHEOPS mission archive which can be found at this link. Proprietary data can only be downloaded by the respective principle investigators using login-credentials, however public data is freely accessible. 

A selection of different types of CHEOPS data is available to help users both to determine the capabilities of CHEOPS (simulated data and data taken during in-orbit commissioning) and to re-reduce any CHEOPS data that they have with their own, bespoke pipelines (reference files). Below is a very brief description of the different types of data, together with a link to where they can be found.

 

Please contact cheops-support at cosmos.esa.int, or kate dot isaak at esa.int replaceing the " dot " and " at " with "."  and "@" respectively incase of any quesitons

 

Last updated:  8 June 2021

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1. data takEN during in-orbit commissioning (January - March 2020)

A selection of 4 data sets taken during in-orbit commissioning is available directly from the CHEOPS mission archive at this link.

The data has been reduced using the data reduction pipeline version cn02-20200619T125718

Details of the observations, together with the results of the data reduction, can be found in the individual reports which are generated automatically by the data reduction pipeline. These can be downloaded from this page by clicking on the target names below, as well as from the mission archive directly.

  • A c. 47 hr duration observation of HD88111, a relatively bright (magnitude V= 9.18), G5 dwarf star (Teff=5330K, R=0.9Rsun), chosen to determine the photometric precision that can be achieved for bright stars. The particular target was picked because of its a-priori relative lack of stellar activitiy, and because it was not known to host an exoplanet. The observations were made on 22 February 2020 (PR300005_TG000101)
  • A c. 47 hr duration observation of  TYC5502-1037-1, a fainter (magnitude V= 11.9) K-type dwarf star (Teff=4750K), radius R=0.7Rsun), chosen to determine the photometric precision that can be achieved for fainter stars. The particular target was picked because of its a-priori relative lack of stellar activitiy, and because it was not known to host an exoplanet. The observations were made on 21 March 2020 (PR300005_TG000501)
  • A c. 1 hr observation of Pollux, a magnitude V= 1.12 dwarf star, considered to be an ultra-bright target for CHEOPS. The observations were made on 10 March 2020 (PR300050_TG000101). It should be noted that the data reduction pipeline is not currently optimised for processing obssrvations of ultra-bright targets, which is reflected in the performances that are reported in the data reduction pipeline report.
  • A c. 10 hr observation of HD93396, an evolved subgiant (magnitude V= 8). Included in the data is the transit of Kelt 11b, a hot-Jupiter with an orbital period of just under 4.74 days (see web article for further details). The observations were made on 9 March 2020 (PR300024_TG000101). Note: to find the data in the CHEOPS mission archive you will need to search for KELT- 11b)

A discussion on the analysis of observations of HD88111, TYC5502-1037-1 and Kelt 11b can be found in the paper on CHEOPS by Benz et al. (submitted May 2020), as well as in a presentation summarising IOC performances that has been prepared by the CHEOPS Mission Consortium, and can be found at this link. Details of the CHEOPS data reduction approach and pipeline can be found in Hoyer et al. (2020) A&A, 635, A24.

In November 2020 three additional CHEOPS observations were made public:

  • A c. 18.5 hr observation of TOI 1233 (TIC 260647166, HD 108236), a relatively bright (magnitude V= 9.25, G=9.09), G5 dwarf star (Teff=5720K, R=0.9Rsun) hosting multiple planets. The observations were made on 10 March 2020 (PR300046_TG000101). To find the data in the archive you will need to either search on either the target coordinates or using the target name TESS_260647166.
  • A further two observations of ultrabright stars, for which again it should be noted that as of 2020 the data reduction pipeline is not optimised for processing observations of ultra-bright targets which is reflected in the performances that are reported in the data reduction pipeline reports.
    • A c. 1 hr duration observation of Fomalhaut, a magnitude V= 1.16, A3 dwarf star (Teff=8590K, R=1.8 Rsun), observed to further explore the photometric precision that can be achieved for very bright stars. The observations were made on 20 August 2020 (PR300058_TG000201).
    • A c. 1 hr duration observation of Altair, a magnitude V= 0.76 A7 delta Scuti-type star, observed to further explore the photometric precision that can be achieved for very bright stars.. The observations were made on 20 August 2020 (PR300068_TG000101).
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In early June 2021 the first CHEOPS phase curve - of 55 Cnc e - and a primary transit of the same planet were made public. The obserations were made during and shortly after IOC. The datsa reduction pipeline reports for the c. 26 hour phase curve observation taken over 23-34 March 2021 and the c. 6 hr transit observation taken on 9th March 2021 can be found here (phase curve: transit). The paper on the observations by Morris et al. (2021) includes a detailed discussion of spacecraft and instrument-related systematics introduced into the CHEOPS light curves and how they are corrected for in the analysis. An overview of systematics seen in CHEOPS light curves is given in a presentation prepared by the CHEOPS Science Team which can be found here. Version 13.1.0 of the data reduction pipline was used to process the data.

 

2. simuLated data

Data simulating a selection of representative CHEOPS observations, generated using the simulation tool CHEOPSim, can be downloaded from the link given directly below. The data are described in the Section 2.2.2.2 in the CHEOPS Observers Manual. Included in the tar files are the "raw" data, together with products that are produced by the data reduction pipline during processing. Please read the README file for details on the content of the tar files. Details of CHEOPSim can be found in Futyan et al. (2020) A&A 635, A23.

Download instructions

  • cheops_fc@ssh.esac.esa.int  (password given at this link)
  • Then change directory to Simulated_data (cd Simulated_data)

 

3. Reference DATA/files

There are number of files which contain data which is used by the data reduction pipeline. These so-called reference files include:

  • EXT_APP_DE1
  • EXT_PRE_StarCatalogue
  • REF_APP_BadPixelMap
  • REF_APP_BiasFrame
  • REF_APP_DarkFrame
  • REF_APP_FlatField
  • REF_APP_WhitePSF
  • REF_APP_OversampledWhitePSF
  • REF_APP_CCDLinearisation
  • REF_APP_GainCorrection
  • REF_APP_Throughput 
  • REF_APP_SED
  • REF_APP_PixelScale
  • REF_APP_QE
  • REF_APP_Limits-ScienceHk
  • REF_APP_ObtReset

A description of the contents of each of FITS files can be found in the Data Product Description Document which can be downloaded here. The files themselves are available from the CHEOPS mission archive, and can be found by querying for reference files.

Details of the CHEOPS data reduction approach and pipeline can be found in Hoyer et al. (2020) A&A, 635, A24, with an overview of the pipeline given in the CHEOPS Observers Manual.