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Link to original content: https://doi.org/10.1051/0004-6361/202039657e
Gaia Early Data Release 3 - Summary of the contents and survey properties (Corrigendum) | Astronomy & Astrophysics (A&A)
Gaia Early Data Release 3
Free Access
Erratum
This article is an erratum for:
[https://doi.org/10.1051/0004-6361/202039657]


Issue
A&A
Volume 650, June 2021
Gaia Early Data Release 3
Article Number C3
Number of page(s) 7
Section Catalogs and data
DOI https://doi.org/10.1051/0004-6361/202039657e
Published online 16 June 2021

This is a corrigendum for Gaia Collaboration (2021). It corrects errors in Sects. 6.3.2 and 7.2 and Appendix A, which erroneously state that the correction to the G-band fluxes and magnitudes presented in Riello et al. (2021) (their Table 5) should be applied to sources in Gaia EDR3 with six-parameter astrometric solutions. In fact, the corrections should be applied to sources with two-parameter or six-parameter astrometric solutions. The corrected Astronomical Data Query Language (ADQL) query and Python source code from Appendix A are presented in the new version of Appendix A below.

Following the discovery of the above error, a more detailed investigation was done for the sources with two-parameter (2-p) astrometric solutions. Out of the 344 million 2-p sources present in Gaia EDR3, about 20 million have an astrometric solution in which the actual source colour was used instead of a default colour. This means that for these 20 million 2-p sources the G-band correction should actually not be applied. These sources are mostly faint, with 96% at magnitudes G > 20, and for 75% of these 20 million sources the correction that is (wrongly) applied amounts to less than 4 milli-magnitudes. It was thus decided not to make a special effort to exclude these sources from the correction. Should a user of the Gaia EDR3 data wish to undo the wrong correction for one or more of these 20 million sources, the list of source IDs and applied corrections can be provided on request.

Appendix A G-band corrections for sources with two-parameter or six-parameter astrometric solutions

Figure A.1 shows how to formulate an ADQL query, to be executed in the Gaia EDR3 archive, that contains an on-the-fly calculation of the corrected G-band fluxes or magnitudes. These queries are somewhat complex and create a performance overhead. Hence downloading the requisite Gaia EDR3 fields and calculating the corrections a posteriori may be more efficient. Example Python code to do this is included in Fig. A.2. The Python code is also available as a Jupyter notebook1.

thumbnail Fig. A.1

Example queries that can be submitted to the Gaia archive in ADQL to retrieve corrected G-band photometry.

thumbnail Fig. A.2

Python code for calculating the corrections to the G-band photometry for sources with two-parameter or six-parameter astrometric solutions.

References

  1. Gaia Collaboration (Brown A. G. A., et al.) 2021, A&A, 649, A1 [NASA ADS] [CrossRef] [EDP Sciences] [Google Scholar]
  2. Riello, M., De Angeli, F., Evans, D. W., et al. 2021, A&A, 649, A3 [Google Scholar]


© ESO 2021

All Figures

thumbnail Fig. A.1

Example queries that can be submitted to the Gaia archive in ADQL to retrieve corrected G-band photometry.

In the text
thumbnail Fig. A.2

Python code for calculating the corrections to the G-band photometry for sources with two-parameter or six-parameter astrometric solutions.

In the text

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