It is not clear that it's worth the computational cost and model complexity to attempt to fit the narrow and broad helium lines. At the moment we fit the following:
The narrow helium lines are tied to the narrow Balmer lines and the broad helium lines are tied to the broad Balmer lines.
I propose dropping the following lines:
hei_broad_4471
heii_broad_4686
hei_broad_5876
In addition, I propose fitting heii_4686independently of the Balmer lines. HeII is a high-ionization line which is very rarely see in normal galaxies (with the exception of extremely metal-poor systems) and in QSOs it's not crazy to think that its kinematics (line-width and velocity shift) will be different than other lines (in the same way that we independently fit HeII 1640).
It is not clear that it's worth the computational cost and model complexity to attempt to fit the narrow and broad helium lines. At the moment we fit the following:
The narrow helium lines are tied to the narrow Balmer lines and the broad helium lines are tied to the broad Balmer lines.
I propose dropping the following lines:
In addition, I propose fitting
heii_4686independently of the Balmer lines. HeII is a high-ionization line which is very rarely see in normal galaxies (with the exception of extremely metal-poor systems) and in QSOs it's not crazy to think that its kinematics (line-width and velocity shift) will be different than other lines (in the same way that we independently fit HeII 1640).Thoughts?