Table 2
Root mean square thresholds (in %) for the different photometricity source distributions.
| Sources | Photometric | Non-photometric |
|
|
||
| SkyProbe | <2.5 | >3.5 |
| SNIFS guide star | <2.5 | >5 |
| SNIFS photometry | <2.5 | >4 |
| SNIFS standard stars | <2.5 | >4 |
Notes. For values intermediate between the photometric and non-photometric thresholds, a combination of indicators is used to ascertain the temporal stability of the atmospheric transmission.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.