C3R2 Quality Flags
The C3R2 quality flags range from 0 to 4, with 4 indicating the highest confidence redshift and 0 indicating that no redshift could be found.
| Quality | Description |
|---|---|
| 4 | Unambiguous redshift identified with multiple features or the presence of the split [O II]λλ3726, 3729 doublet. |
| 3.5 | A high-confidence redshift based on a single line, with a very remote possibility of an incorrect identification. An example might be a strong, isolated emission line identified as Hα, where other identifications of the line are highly improbable due to the lack of associated lines or continuum breaks. This flag is typically only adopted for LRIS and MOSFIRE spectra. |
| 3 | A high-confidence redshift with a low probability of an incorrect identification. An example might be the low signal-to-noise ratio detection of an emission line, possibly corrupted by telluric emission or absorption, identified as [OII]λλ3726, 3729, but where the data quality is insufficient to clearly resolve the doublet. |
| The following quality ranges not included in the data release | |
| 2/1 | 2 indicates a reasonable guess, while a quality flag of 1 indicates a highly uncertain guess. Sources with these low-confidence redshifts are not included in the data release. |
| 0 | No redshift could be identified. As described next, a code indicating the cause of the redshift failure is assigned in place of the redshift. |
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