The sky emission in HSIM datacubes shows skylines at their vacuum wavelengths, whereas they shall appear at their air wavelength (CTYPE3='AWAV').
For example the skyline shown below is peaking in HSIM at 19839.728 Angstroms which is the vacuum wavelength of the OH line (Rousselot et al. 2000, blue dashed line), whereas the air wavelength is shown at 19834.313 Angstroms which is the air wavelength of the same OH line (same reference). For comparison the HINM which makes use of skycalc in air wavelengths is shown in black.
Hi,
The sky emission in HSIM datacubes shows skylines at their vacuum wavelengths, whereas they shall appear at their air wavelength (CTYPE3='AWAV').
For example the skyline shown below is peaking in HSIM at 19839.728 Angstroms which is the vacuum wavelength of the OH line (Rousselot et al. 2000, blue dashed line), whereas the air wavelength is shown at 19834.313 Angstroms which is the air wavelength of the same OH line (same reference). For comparison the HINM which makes use of skycalc in air wavelengths is shown in black.