The hard-coded host-galaxy line list uses inconsistent wavelength conventions. In particular, the [O II] doublet is listed as:
For a vacuum-wavelength list, it should be approximately 3727.09 and 3729.88; for an air-wavelength list, approximately 3726.03 and 3728.82. Most of the other entries, such as Hα at 6564.61 Å and Hβ at 4862.69 Å, are vacuum wavelengths.
The complete list is subsequently passed through pyasl.airtovac2, which also converts the already-vacuum entries a second time and shifts the line centers by roughly 83 km/s.
This occurs in:
- NGSF/Header_Binnings.py
- NGSF/SF_functions.py
- The legacy top-level Header_Binnings.py
I suggest standardizing the list on vacuum wavelengths, changing the first [O II] component to 3727.09 Å, and removing the air-to-vacuum conversion.
The hard-coded host-galaxy line list uses inconsistent wavelength conventions. In particular, the [O II] doublet is listed as:
For a vacuum-wavelength list, it should be approximately 3727.09 and 3729.88; for an air-wavelength list, approximately 3726.03 and 3728.82. Most of the other entries, such as Hα at 6564.61 Å and Hβ at 4862.69 Å, are vacuum wavelengths.
The complete list is subsequently passed through
pyasl.airtovac2, which also converts the already-vacuum entries a second time and shifts the line centers by roughly 83 km/s.This occurs in:
I suggest standardizing the list on vacuum wavelengths, changing the first [O II] component to 3727.09 Å, and removing the air-to-vacuum conversion.