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Which iDR4 parameters should be used for science publications?

GESiDR4 is a full release. All observations from the beginning of the survey until July 2014 are included, which is 2.5 years of observations.

For iDR4 the homogenisation of the stellar atmospheric parameters, individual element abundances, radial velocities and UVES rotational velocities have been completed to the Recommended level. Previously only radial velocities and stellar atmospheric parameters were homogenised to the Recommended level. gamma index, chromospheric activity, Hα emission measurements, and mass accretion rates are also provided (by WG12 only).

All Recommended values are contained in table RecommendedAstroAnalysis.

Specific issues with GESiDR4 results are listed as follows:

1. S/N can be extracted from the Spectrum table. However the S/N for the GIRAFFE spectra are overestimated (in particular for high S/N values) due to an issue in the algorithm and are not considered as Recommended products.
2. Recommended radial velocity values and errors are contained in VRAD and E_VRAD respectively in RecommendedAstroAnalysis. VRAD with error greater than 10 km/s are flagged in column TECH as 9021.
3. Recommended rotational velocity values and errors are contained in VSINI and E_VSINI. Only UVES values are recommended due to a bug in the GIRAFFE rotational velocity algorithm. GIRAFFE values can be retrieved from the Spectrum table. However, they are not recommended and should be used with caution. Permission from the PIs must be obtained for the use of these in any publications.
4. Any value not taken from the RecommendedAstroAnalysis table requires PI permission for use in any publication.