STEPS TOWARD POLAR MAPPING

1. Simulate a telemetry file (or get real telemetry file)
   • event_obj = Obj_New( 'hsi_eventlist' )
   • event_obj-->Simulate (input your preferred model )
   • event_obj-->WriteTelemetry
   • event_obj-->WriteFITS

2. Create Calibrated Event List
   • ceo = Obj_New( 'hsi_calib_eventlist' )
   • det_index=4 ; or any other number from 0 to 8
   • coll =ceo-->getcalibeventlist(det_index,filename='telemetry.fits')
     • calib_event.roll_angle
     • calib_event.phase_map_ctr
     • calib_event.gridtran
     • calib_event.livetime
     • calib_event.count
     • calib_event.modamp
     • calib_event.background

3. Select 180^o subset of roll angles (average only after step 7.)
4. Find approximate flare location
   • External information (H, SXT, OVRO, SERBL?)
   • Internal information (modulation rate or bproj map)
   • Trial and error
5. Select map center (The closer to flare, the better the vis)
6. Generate modulation profile (rebin appropriately)
7. Generate visibilities (modprofile_to_vis.pro)---average mod 180
   • spin-based (Triassic version)
   • phase-based, non object-oriented (Jurassic version)
   • phase-based, object-oriented (Paleolithic version)
     • Note in progress: puzzling sign of imaginary part
     • Uncertain effect of least-square fit on statistics.
   • Pleistocene version--Real Soon Now

8. Select polar center (x_pol_ctr,y_pol_ctr) -- near spin axis or Sun center
   • q = (U,V), depends on det_index, grid_angle, roll_angle
   • R =
9. Shift phases to polar center:

10. Apply polar recipe:
    1. Read the visibility amplitude and phase vectors .

    2. Compute the FFT in space for each complex vector V, obtaining the complex coefficients .

    3. Using downward recurrence relations, compute the matrix

    4. For each radius (R) in the map and each collimator (j), compute the vector

    5. Obtain the one-dimensional FFT, giving the dependence at that radius (one column of a single-subcollimator map).

    6. Add the one-collimator maps together, weighting by the UV radius .

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