Sky Coordinate Image Specs

• Fully processed:– Merged– 10-min cadence– “sky to sky” interpolation– Gaussian temporal filter– Renormalized such that

time is centered– Treatment of poles will be

considered further & tested.

– SolarSoft & WCS compliant headers

• Quick look:– Processed at each site– Full resolution– Bad images removed– 2 consecutive 5-min

averages returned every hour

– Staggered around network by 20 min

– No interpolation (if jitter < 1 pixel)

– Approximate calibration– Evaluate jitter– Provide image geometry (ie

P angle)

Remapped images

• Full Reduction– Single-site @ 1 min – Merged @ 10 min– Temporal filter same as sky coord images– Spatial resolution to match disk center in longitude & sin lat– Specify heliocentric coordinates with a constant gird, not

heliographic (see next slide)– For 10-min average, no need to correct for differential rotation– Space pixel coordinate definition consistent with temporal

definition– Include specification of CR Time in header

• Quick look– Produced from quick-look sky images

Definition of heliocentric coordinates

• 0,0 is at central meridian, solar equator

• Longitude coordinate is angular distance from central meridian

• Sin latitude coordinate is measured from equator

Synoptic maps

• Full processing:– Merged, uniform noise level– Need differential rotation correction– Create usual synoptic map (once every

CR) w. cos4 weights, 1-degree resolution

– Create high-res synoptic map, once per CR, narrow weights, match disk center resolution (or use 0.2 degrees, will test)

– Create “Best” global map:• Cadence: 1 hr goal, 4 hr

requirement • Spatial resolution: matched to disk

center, • Spatial weighting function is broad,

± 60°, temporal weighting is narrow• Consider creation on demand

– Do not match SOLIS cadence, try for compatible data format

– Location of missing data should be identified

– Fill poles like SOLIS– Treat LOS projection like

SOLIS• Quick look:

– Spatial resolution: 1 degree– 1-hr (goal) or 4-hr cadence

updated map– Constructed from quick-look

sky images– Leave hook to include flux

transport for backside fields, but don’t include for now.

Synoptic map defintions

• Usual synoptic map: covers 1 Carrington rotation, contains all central meridian data available, created once per CR.

• Best global map: created frequently, includes data obtained after target time of map.

• Updated map: like Best global map, but contains only data prior to target time.

Data distribution

• Maintain access to on-line quick-look jpegs

• Movies

• Separate web page for magnetograms

• Calendar & clock graphical search tools

Older data

• Make available jpegs of either on-demand or all single site sky images, registered & centered, no ZPC

• How much jpeg compression is acceptable? Jpeg2000?• Evaluate cost of applying current ZPC, either on

demand, or for entire set. Estimate time required for processing & development.

• Work with Yan Li to test ZPC for LCT• Consider constructing a registered merged ZPC’ed

movie for a SHINE interval• Make data limitations clear on the web page, perhaps in

header

Additional Processing

• Cross-site sensitivity:– Use Harry’s code to see

how big the problem is– Characterize temporal &

site-dependent behavior– Perhaps use global

optimization to remove relative variation in network

– Absolute reference from external source

• Spherical Harmonics:– Yes, on synoptic maps– Adopt Wilcox normalization– Max degree 50

• Potential Field Extrapolation:– Provide “hairy ball” pictures– Provide links to other

sources of results– Provide data to groups with

existing code (e.g. CCMC)

Additional processing II

• Destretching:– Test effectiveness & cost of correcting RCP &

LCP distortion– Consider adapting Lockheed code, or Harry’s

code.

• Restoration:– Lower priority– Might be useful to smooth noise variations

Zero Point Correction

• Destretch RCP + LCP of reference magnetograph

• Characterize new modulator response

• Apply existing ZPC to new data, evaluate results.