EIT, MDI, Mapping and SSW techniques

Created by freeland at Tue Feb 9 07:23:49 1999 at MEDOC Last revision by freeland at Fri Feb 22 17:45 at LMSAL

SSW environment setup

Include eit mdi trace sxt in your SSW_INSTR list

Find, read , and prep an eit image (L0->L1)

IDL> eitf=eit_files('00:00 2-jun-1998',/full,wave=171) ; Find the data

IDL> read_eit, eitf, eindex, edata ;Read the data

IDL> eit_prep, eindex, data=edata, oeindex, oedata ; (optional) PREP the data (eit,trace,sxt)

Apply the Mapping software to the EIT L1 data just created

IDL> sdata=sobel_scale(oeindex, oedata, minper=5,hi=2000) ; (optional) scale the data

IDL> index2map, oeindex, sdata, eitmap ; make a map

IDL> plot_map, eitmap, grid=15, xsize=1024 ; plot the map with a solar grid

IDL> oplot_nar, anytim(oeindex, /ecs) ; overplot NOAA Active Region info

IDL> index2map, oeindex, sdata, subeitmap, /sub ; define/generate a sub region map

You will be graphically prompted to select a sub region
Use the left mouse button to move the box, the center button to resize and the right button to select/quit
For this demo, select AR 8227

Do some coordinated analysis with MDI

IDL> mdif=mdi_files(oeindex) ; find MDI file closest in time to your EIT image

IDL> rd_mdi, mdif, mindex, mdata ; read mdi index,data

IDL> index2map, mindex, mdata, mdimap, ref_sub=subeitmap ; make the corresponding mdi map using eit sub reqion map as reference (index2map calls sub_map internally

IDL> plot_map, mdimap,/over,/rotate,/positive,lcolor=!p.color, drange=[-500,500] ; overplot rotated postitive polarity
IDL> plot_map, mdimap,/over,/rotate,/negative,lcolor=0,drange=[-500,500] ; overplot contours for rotated negative polarity

IDL> oplot_nar,anytim(oeindex,/ecs) ; overplot NOAA Active Region info

Play with some plot_map parameters

For example, parameters FOV (size in arcminutes of field) and CENTER (of FOV) coordinates in arcseconds [EW,NS] permit zooming in and out and changing center of field of view.

IDL> plot_map,eitmap,grid=10,center=[-900,300],fov=10 ; zoom in on NorthEast limb

Detailed Mapping Package documentation by Dominic Zarro http://orpheus.nascom.nasa.gov/~zarro/idl/maps.html

Illustrate some "standard" SSW tools, utplot, evt_grid, anytim, time_window, grid_data, xstepper..."

Pseudo-ProblemFind all eit 171 files in time range - subselect one image every 24 hours, read them and process them (dark and grid corrections)

IDL> efiles=eit_files('25-may-1998','8-jun-1998',wave=171,/full)
IDL> ss=grid_data(file2time(efiles),hour=24)
IDL> read_eit,efiles(ss),eindex, edata
IDL> eit_prep, eindex, data=edata, outindex, outdata
IDL> sdata=sobel_scale(outindex, outdata, minper=5,hi=2000)
IDL> xstepper, sdata, anytim(outindex,/ccsds)

Plot GOES light curve for the period - annotate with EIT and closest MDI image times. Note dbase input is in the form of EIT index records
IDL> wdef,xx,600,400,/ur ; [,/zbuffer]
IDL> linecolors
IDL> time_window, eindex, t0, t1
IDL> plot_goes,t0,t1,/one_minute,background=11
IDL> evt_grid, eindex, tickpos=.9, color=5,thick=2

Find and read MDI images closest in time to the above EIT images.
IDL> mdifiles=mdi_files(eindex,ftimes=ftimes)
IDL> rd_mdi, mdifiles, mindex
IDL> evt_grid, mindex, tickpos=.85, color=7,thick=2

freeland@sxt1.lmsal.com