1. HMI Status P. Scherrer

2. Origin of Solar Variability
HMI Primary goal
Origin of Solar Variability
The primary goal of the Helioseismic and Magnetic Imager (HMI) investigation is to study the origin of solar variability and to characterize and understand the Sun’s interior and the various components of magnetic activity.
HMI produces data to determine the interior sources and mechanisms of solar variability and how the physical processes inside the Sun are related to surface and coronal magnetic fields and activity.

3. SDO HMI Instrument on SDO EVE AIA HOP HEB HMI HMI InstrumentX Z Y
EVE
AIA
HOP
HEB
HMI
SDO
HMI Instrument
HMI Optics Package (HOP)
HMI Electronics Box (HEB)
Intra Instrument Harness
Flight Software

4. All moved in!
HOP
HEB
Harness

5. HMI is Ready The HMI instrument was delivered to NASA last November
HMI is integrated onto SDO
HMI will meet “Level-1” observing requirements
It is a fine instrument, we are very pleased with it
There are a few minor issues that must and will be resolved in the coming month or two, e.g.:
A few flight software issues expected to be resolved by May
Front window birefringence change with temperature to be explored with spare
There are a few minor issues that will be resolved after launch, e.g:
Temperature control method and variations during orbit
Tuning parameters for data compression - variations with tuning and polarization
There are a few items to be determined after launch, e.g.:
“Best” framelist for observing sequence
Can we combine data from both cameras to compute “Observables”
The internal structure and dynamics of the Sun and the sources of solar variability

6. So, the first 6 years work of many got the instrument done
but we are not yet ready for data to flow or to accomplish the science..

7. Primary Science Objectives
Convection-zone dynamics and solar dynamo
Structure and dynamics of the tachocline
Variations in differential rotation.
Evolution of meridional circulation.
Dynamics in the near-surface shear layer.
Origin and evolution of sunspots, active regions and complexes of activity
Formation and deep structure of magnetic complexes.
Active region source and evolution.
Magnetic flux concentration in sunspots.
Sources and mechanisms of solar irradiance variations.
Sources and drivers of solar activity and disturbances
Origin and dynamics of magnetic sheared structures and delta-type sunspots.
Magnetic configuration and mechanisms of solar flares and CME.
Emergence of magnetic flux and solar transient events.
Evolution of small-scale structures and magnetic carpet.
Links between the internal processes and dynamics of the corona and heliosphere
Complexity and energetics of solar corona.
Large-scale coronal field estimates.
Coronal magnetic structure and solar wind
Precursors of solar disturbances for space-weather forecasts
Far-side imaging and activity index.
Predicting emergence of active regions by helioseismic imaging.
Determination of magnetic cloud Bs events.

8. HMI Science Analysis Plan
Tachocline
Differential Rotation
Meridional Circulation
Near-Surface Shear Layer
Activity Complexes
Active Regions
Sunspots
Irradiance Variations
Flare Magnetic Configuration
Flux Emergence
Magnetic Carpet
Coronal energetics
Large-scale Coronal Fields
Solar Wind
Far-side Activity Evolution
Predicting A-R Emergence
IMF Bs Events
Brightness Images
Global
Helioseismology
Processing
Local
Version 1.0w
Filtergrams
Line-of-sight
Magnetograms
Vector
Doppler
Velocity
Continuum
Brightness
Line-of-Sight
Magnetic Field Maps
Coronal magnetic
Field Extrapolations
Coronal and
Solar wind models
Far-side activity index
Deep-focus v and cs
maps (0-200Mm)
High-resolution v and cs
maps (0-30Mm)
Carrington synoptic v and cs
Full-disk velocity, v(r,Θ,Φ),
And sound speed, cs(r,Θ,Φ),
Maps (0-30Mm)
Internal sound speed,
cs(r,Θ) (0<r<R)
Internal rotation Ω(r,Θ)
(0<r<R)
Vector Magnetic
Field Maps
Science Objective
Data Product
Observables
HMI Data
Magnetic Shear

9. HMI Standard Product Pipeline
Processing
Data Product
HMI Data
Spherical
Harmonic
Time series
To l=1000
Internal rotation Ω(r,Θ)
(0<r<R)
Filtergrams
Heliographic
Doppler velocity
maps
Mode frequencies
And splitting
Internal sound speed,
cs(r,Θ) (0<r<R)
Full-disk velocity, v(r,Θ,Φ),
And sound speed, cs(r,Θ,Φ),
Maps (0-30Mm)
Ring diagrams
Local wave
frequency shifts
Level-0
Doppler
Velocity
Carrington synoptic v and cs
maps (0-30Mm)
Tracked Tiles
Of Dopplergrams
Time-distance
Cross-covariance
function
Wave travel times
High-resolution v and cs
maps (0-30Mm)
Egression and
Ingression maps
Wave phase
shift maps
Deep-focus v and cs
maps (0-200Mm)
Far-side activity index
Level-1
Stokes
I,V
Line-of-sight
Magnetograms
Line-of-Sight
Magnetic Field Maps
Stokes
I,Q,U,V
Full-disk 10-min
Averaged maps
Vector Magnetograms
Fast algorithm
Vector Magnetic
Field Maps
Vector Magnetograms
Inversion algorithm
Tracked Tiles
Coronal magnetic
Field Extrapolations
Tracked full-disk
1-hour averaged
Continuum maps
Coronal and
Solar wind models
Continuum
Brightness
Solar limb parameters
Brightness feature
maps
Brightness Images
HMI Data Analysis Pipeline

10. Status of HMI Science Processing Plan Development
Data analysis pipeline: standard helioseismology and magnetic field analyses will produce “Standard” data products
“Level-1” Observable program development just now getting started.
None of the “pipelines” are functioning yet.
Most pipeline elements need updated software.
Targeted numerical modeling is proceeding.
Focused data analysis and science working groups continue to be important.
Joint investigations with AIA and EVE need development.
Cooperation with other space- and ground-based projects (SOHO, Hinode, PICARD, STEREO, RHESSI, GONG+, SOLIS, HELAS) needs development.
After this meeting we will evaluate which pipeline elements must proceed with existing algorithms and code and which will get improvements.
It is clear that “standard products” will evolve early in the mission.

11. Summary
The HMI Instrument is ready to provide key data to study the Sun’s dynamics and magnetism: subsurface flow maps and photospheric vector magnetic fields.
There are some minor issues, some will be fixed and some we will live with.
It needs to be in the sky.
The HMI data analysis plan includes a standard pipeline processing and on demand data analysis tools.
The analysis pipeline is being developed by the Co-I team, using existing techniques and software.
Since many Co-Is do not have funding to prepare, some of the planned data products may not be available at the start of the mission.
Many “Traditional” data product pipelines will be ready if the present rate of development continues.
Work on the “white boxes” will likely wait until after launch.

12. More Details on HMI status follow
DONE
More Details on HMI status follow

13. HMI status Completed mechanical integration with the SDO spacecraft
Optics package alignment is within the requirement
MLI closeout was completed (except for a couple access points)
Completed electrical integration
Discovered low LVDS isolation resistance which indicated ESD damage to LVDS
Completed LVDS rework (see “Changes Since PSR” chart)
HMI completed the stand alone CPT and the observatory CPT#1
HMI hardware is in flight configuration with the following exceptions
Flight software update is planned prior to CPT#2
Need to stake the MLI around the front door
Closeout MLI around alignment cube
Remove red tag items

14. Flight Software Status
Delivered FSW with known issues and planned software update at observatory
Developed a list of software updates with SDO Project based on existing software problem reports and targeted improvements
Incorporate known discrepancies (DAI)
Incorporate IV&V findings
Complete high speed bus (HSB) resynchronization development
Developed software test bed for software testing
Completed most non-HSB related software changes and testing in work
Closed 23 of 26 DAIs and all IV&V findings
Demonstrated most HSB functionality and code is being debugged
Remaining software verification items will be closed upon completion of the next SWAT
Test bed will be used for in-house test prior to delivery
SWAT will be performed upon code update at the observatory level
Software update does not effect EMI/EMC operating modes and analysis
Software update is planned for May 15th at the observatory prior to CPT#2 and thermal vacuum test

15. HMI Observables Performance Issues
In no particular order:
Some scattered light in column direction, small but not well quantified.
MTF measurements still include Stim-Tel, data in hand, needs analysis.
Front window birefringence temp sensitivity, may reduce mag sensitivity
CCD gain stability not well measured.
CCD full well less than expected, but meets min requirements.
Uncertainty best focus setting, but small part of range.
Gravity release change in distortion, field flatness, etc., never tested but some variations when rotated 90 degrees, but small.
Strange up-down motion in Lyot tuning motor/waveplate, requires registration
HSB robustness, possibly fixed – not tested.
Sequencer has some unexplained failures, but rare
Almost no solar data during testing, but some
Flat field not demonstrated at needed level, but close
Antenna induced jitter avoidance not tested, but small.