Presentation is loading. Please wait.

Presentation is loading. Please wait.

Time-Distance Pipeline for the Upper 30Mm Convection Zone Status 11/5/2007.

Similar presentations


Presentation on theme: "Time-Distance Pipeline for the Upper 30Mm Convection Zone Status 11/5/2007."— Presentation transcript:

1 Time-Distance Pipeline for the Upper 30Mm Convection Zone Status 11/5/2007

2 Doppler Velocity Tracked Tiles Of Dopplergrams Filtergrams Time-distance Cross-covariance function Wave travel times Deep-focus v and c s maps (0-200Mm) High-resolution v and c s maps (0-30Mm) Carrington synoptic v and c s maps (0-30Mm) Full-disk velocity, v(r,Θ,Φ), And sound speed, c s (r,Θ,Φ), Maps (0-30Mm) Time-Distance Helioseismology Code: fastrack R.Bogart, T.Duvall J.Zhao Status: needs improvements (remapping issues) Additional funding: none Code: cross- covariance T.Duvall J.Zhao Status: needs improvements Additional funding: none Code: travel time fitting T.Duvall J.Zhao S.Couvidat Status: needs improvements Additional funding: none Code: sensitivity kernels A.Kosovichev J.Zhao A.Birch Status: needs improvements Additional funding: Birch: 2 PM Code: inversions A.Kosovichev J.Zhao, A.Birch S.Couvidat J.Toomre B.Hindman Status: needs improvements Additional funding: Toomre:5 PM Code: deep- focus maps T.Duvall A.Kosovichev J.Zhao Status: needs substantial development Additional funding: need new postdoc at Stanford

3 Task Input: Output: Dopplergrams Active region structures and flows Synoptic flow maps

4 Status: Cross-Covariance Code: cross- covariance T.Duvall J.Zhao Status: needs improvements Additional funding: none Task: Do filtering and compute cross-covariance Status: filtering: code ready, comparisons among Tom, Sebastien and myself have achieved excellent results cross-covariance computation: code ready, comparisons also done, and excellent results achieved selection of annulus pixels: algorithm has been compared between Tom and me, a Fortran code needs to be developed for the active region cases. Synoptic flow maps will use pre-computed locations. Summary: Nearly done except one subroutine for on-fly computation of annulus pixels. Module is needed.

5 Status: Travel Time Fitting Code: travel time fitting T.Duvall J.Zhao S.Couvidat Status: needs improvements Additional funding: none Task: Fit cross-covariances to derive acoustic travel times Status: As of last Friday, comparisons among Tom, Sebastien and myself are still going on. I am optimistic that excellent results will be achieved. Codes in Fortran are largely ready. Only some fine- tuning is needed in some parameters. Fitting code based on Gizon-Birch method was written by Sebastien and ready to be incorporated into main code. Summary: Nearly done except incorporating Sebastien’s subroutine. Module is needed.

6 Status: Sensitivity Kernels Code: sensitivity kernels A.Kosovichev J.Zhao A.Birch Status: needs improvements Additional funding: Birch: 2 PM Task: Compute sensitivity kernels as input for the inversion code Status: Ray-approximation kernels: a few codes exist, some comparisons have been planned to finalize this. Born-approximation: Birch code ready for use with some opitmization that is being carried out by Konstantin. Also MPI can provide this. Summary: in a pretty good shape. Should be finished in a couple of months.

7 Status: Inversions Code: inversions A.Kosovichev J.Zhao, A.Birch S.Couvidat J.Toomre B.Hindman Status: needs improvements Additional funding: Toomre:5 PM Task: Develop code to do inversions Status: Pipeline work on this part is barely started. Codes for two different algorithms (LSQR and MCD) exist. Probably both algorithms will be put into pipeline. Some comparisons between different codes and different algorithms are needed. Summary: Barely anything has been done. A lot of efforts are needed in this. An estimate of 6 months(?) is required for this part of work.

8 Additional Issues Poor or no noise estimations in both time-distance measurements and inversions. This needs a great deal of research efforts to implement it. Not sure whether this part can be accomplished by the time of March 2009. Sebastien has code for inversions with noise covariance. All codes are based on MDI observations. Some parameter changes and more testing is needed for HMI observations. Co-I asks for more support. Overall, it is very optimistic to deliver all codes before March, 2009

9 Computer Requirement Now we are ambitious in computing 17 different annuli for HMI data Computing 17 annuli using 512-minute MDI full-disk data takes approximately1.5 hours on 1 LWS cluster node for 1 of 9 regions selected on solar disk. We do not yet know whether we will use HMI full resolution to do this. We save fitted travel times and inverted 3D velocity and 1D sound-speed perturbation for approximately 15 depths. Every 8.5 hours, it takes 62MB saving space for MDI resolution.

10 Time-Distance Pipeline for Far- side Imaging Status 11/5/2007

11 Task Input: Output: Dopplergrams Far-side images

12 Status All codes for computing travel times are ready in Fortran. Some processing and making of maps after travel times are in IDL. Each far-side map is combined from one 4-skip map and one 5- skip map. Module is needed. Should be able to share a lot of things with holography far-side imaging, hence saving a lot of computing and storage resources. Computer Requirement One map is made every 12 hours Using MDI medium-l data, one map needs about 1 hour computing time using one LWS2 cluster node. Storage space is quite small.

13 Issues No additional support is needed. Though codes are ready, results are published, maps are not widely available online and seen by colleagues. Hence, it is useful to broadcast the results so as to receive feedbacks from colleagues. Statistical study regarding to how much we can believe in those images, which part of images is more reliable and which part is not reliable. Systematic comparison with holography far-side images is probably necessary.

14 Helioseismic Holography Pipeline Status 11/5/2007

15 Doppler Velocity Tracked Tiles Of Dopplergrams Filtergrams Egression and Ingression maps Wave phase shift maps Far-side activity index High-resolution v and c s maps (0-30Mm) Acoustic Holography Code: fastrack R.Bogart D.Braun C.Lindsay Status: needs improvements (field-effect corrections) Additional funding: Braun: 2 PM Code: egression- ingression D.Braun C.Lindsay Status: needs improvements Additional funding: none Code: phase shifts D.Braun C.Lindsay Status: needs improvements (showglass corrections) Additional funding: Braun: 3 PM Code: sensitivity kernels A. Birch Status: in development Additional funding: Birch: 2 PM Code: holographic inversions A.Birch Status: in development Additional funding: Birch: 6 PM Lindsay: 6 PM Programmer: 0.5 PM Code: Far-side imaging P.Scherrer C.Lindsay D.Braun Status: needs improvements Additional funding: Lindsay: 4 PM Programmer: 0.5PM Inversions

16 Status (I) Code: egression- ingression D.Braun C.Lindsay Status: needs improvements Additional funding: none Code: phase shifts D.Braun C.Lindsay Status: needs improvements (showglass corrections) Additional funding: Braun: 3 PM Task: Compute egression and ingression functions, and measure acoustic phase shifts by cross- correlating egression and ingression Status: Codes are essentially existing for MDI- type data, though some improvements are necessary, and some tuning to fit HMI is also required.

17 Status (II) Code: sensitivity kernels A. Birch Status: in development Additional funding: Birch: 2 PM Code: holographic inversions A.Birch Status: in development Additional funding: Birch: 6 PM Lindsay: 6 PM Programmer: 0.5 PM Task: Compute sensitivity kernels, and invert for flow fields based on phase-shift measurements Status: Still under development. Only very limited experimental coding has been developed.

18 Status: Far-side Imaging Code: Far-side imaging P.Scherrer C.Lindsay D.Braun Status: needs improvements Additional funding: Lindsay: 4 PM Programmer: 0.5PM Status: Codes are ready and are already run in MDI pipeline, though retooling to HMI is needed. Researches on corrections, calibrations and near- side limb imaging are carried out, but do not yet promises anything for updating or improving for HMI pipeline.

19 Issues Nearly all codes are needed to be re-adjusted to HMI. Without additional funding, the codes they provide will be quite limited in utility and scope: * use local plane-parallel geometry; * have limited or no corrections in large-scale artifacts * no treatment on magnetic surface effect * far-side images will have little or no calibration.


Download ppt "Time-Distance Pipeline for the Upper 30Mm Convection Zone Status 11/5/2007."

Similar presentations


Ads by Google