SHARP data product
SHARP means Space-weather HMI Active Region Patch.
It is the HMI data product that packages active-region magnetic-field observations into tracked patches. For NF2, this is the practical source of the lower-boundary vector magnetogram.
Common JSOC series are:
hmi.sharp_720s
hmi.sharp_cea_720sFor HMI active-region extrapolation, hmi.sharp_cea_720s is usually the convenient choice because it provides the remapped CEA vector components Br, Bp, and Bt.
SHARP versus HARP
- SHARP is the data product or series.
- HARP active-region patch ID is the tracked patch number used to index the series.
Analogy: SHARP is the database table; HARP is the row ID. Crude, but it keeps the wiring straight.
Why SHARP is the right product here
NF2 needs vector magnetic boundary data, not just a context image. SHARP provides that in a form designed for active regions.
For the standard CEA route:
hmi.sharp_cea_720sgives remapped components at 12-minute cadence, which is exactly what the NF2 FITS loader expects for the normal HMI workflow.
SHARP versus other solar data sources
- JSOC/SHARP: use for the active-region vector magnetogram boundary.
- AIA/EUV images: use for visual context and loop comparison, not as the magnetic boundary.
- Helioviewer/VSO: useful for discovery and context, but not the exact SHARP component triads needed by NF2.