Free Access
Table 1
Parameters used for extracting the filling factors of the umbra and penumbra and of faculae from SOHO-MDI synoptic charts of photograms and magnetograms.
| Parameter | Value |
|
|
|
| B Noise | 50 G |
| B sat | 450 G |
|
|
|
| limit penumbra | 90% of median intensity at distance μ |
| limit umbra | 60% of median intensity at distance μ |
|
|
|
| extraction uncertainty: | |
| penumbra | 100 ppm (≈100% in solar minimum 1996) |
| umbra | 50 ppm (≈100% in solar minimum 1996) |
|
|
|
| latitude range | μ ≥ 0.43 (low latitudes between ± 65°) |
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.