The emission line is assumed to be monochromatic at the specified wavelength and redshift / velocity.
You can either:
- Select an emission line from the menu and specify a redshift / velocity.
- Manually specify a rest wavelength and a redshift / velocity. Choose "Specify" on the line menu.
- Manually specify the observed wavelength and set redshift / velocity to zero. Choose "Specify" on the line menu.
Velocities should be given in km s-1. Note that Doppler shift calculations are fully relativistic.
Four example inputs are shown below. These are all equivalent and give the same result. The line flux is 1.2x10-14 erg cm-2 s-1, and the observed line wavelength is 5082 Angstroms.