Calibration

In order to flux calibrate your data, an appropriate spectro-photometric standard star must be chosen and observed. The standard stars that are compatible with the pipeline can be found in the kcwidrp/data/stds directory in the pipeline install directory (KCWI_DRP). In that directory, you will find a WMKO starlist file called kcwi_stds_starlist.txt with the stars in RA order.

You will also find in that directory plots of each standard star showing the wavelength sampling and coverage for each standard star reference file. Once you have defined your configuration, it is recommended that you examine the star list to narrow down the list of available standards during your observing run, and then examine the plots of your narrowed list to be sure that any standard you select is well sampled and covers the wavelength range of your configuration.

You can also examine the standard star plots in the github repository by following this link. Click on the *.png files and they should display in your browser with flux versus wavelength and the reference samples indicated by plus (+) signs.

Be aware that high resolution configurations usually cover smaller wavelength ranges and in that case, you will need to find a densely sampled standard star. You will need at least five points within your wavelength range, although this will only provide a crude calibration (which may be appropriate for your needs).

If you copy the entries for the standards you want to observe from the starlist here into your own starlist, then the observations will have the correct object names, making sure the pipeline will recognize them. This is highly recommended.