MaStar Special Stars
LSF Calibration Stars
MaNGAID '53-1342755' (HD 37828)
For calibrating the line spread function (instrumental broadening kernel, LSF), we have observed one special plate which includes one star that belongs to many other stellar libraries. Star HD37828 is included in the ELODIE library, the MILES library, and the X-Shooter Spectral Library. This star has MaNGAID='53-1342755' and was observed on plate 9676 with IFUDESIGN 12704, using very short exposure times.
The direction of this plate has significant galactic extinction. The amount of extinction in front of the standard stars on this plate are much smaller than what is given by the dust map used by the pipeline. This leads to incorrect flux calibration on this plate, setting the POORCAL bit in the quality bitmask. If one wants to use the spectrum of this star, special correction needs to be applied.
This flux calibration issue due to uncertain extinction in front of standard stars will be fixed in future data releases.