VLT UVES

Overview

This file summarizes several instrument specific settings that are related to the VLT/UVES spectrograph. PypeIt supports the reduction of all UVES setups, but it does not currently support reduction with image slicer. While detailed documentation doesn’t currently exist for VLT/UVES, you may find it helpful to look at the documentation for Keck/HIRES, which is a similar echelle spectrograph. See Keck HIRES for details on that instrument.

MOSAIC

PypeIt, by default, uses a mosaic approach for the reduction. Since there are two separate arms, PypeIt will reduce the blue arm (vlt_uves_blue) separate from the red arm (vlt_uves_red). The red arm consists of a two detector mosaic (l and u). PypeIt constructs a mosaic of the l and u detector data and reduces it, instead of processing the detector data individually. The mosaic reduction is switched on by setting the parameter detnum in ReduxPar Keywords to be a tuple of the detector indices that are mosaiced together. For the red arm of UVES, it looks like:

[rdx]
    spectrograph = vlt_uves_red
    detnum = (1,2)

This is already the default for the red arm of UVES, but the user can modify it in the PypeIt Reduction File to turn off the mosaic reduction.

Calibrations

Wavelengths

See Echelle Spectrographs for details on the wavelength calibration.

Additional Reading

Please also refer to the Keck HIRES tutorial for more details on the reduction of echelle spectrograph data. See Keck HIRES for details on that instrument.