Oberon Version

Ian M George: Extract Standard files from the EVT2

These pages are unofficial in all respects. They are primarily simply notes to myself. The information is not guaranteed to be correct or up-to-date.

Last Updated: 2004 Jun 30
Starting Point... OK, so now we have an evt2 file called cleaned.evt2. We are now going to extract some standard files from it..

The Standard Event Files

Simply run the script
/data/oberon5/george/data/axaf/scripts/sep_hetg.csh
This will make a whole bunch of event files (using the FTOOL fselect) based on flags set in cleaned.evt2 by the previous steps. These include events assigned to the 0th-order, along with MEG and HEG events in their respective +ve & -ve 1st-, 2nd- & 3rd-orders.

The Standard Images of the Dispersed Spectra

Simply run the script
/data/oberon5/george/data/axaf/scripts/meg_disp_img.csh
This will make standard images. Now Display these images using fv (one at a time)
fv meg_clnd_o1_01000_04500_both_wave_vs_tg_d.img_a05 &
fv meg_clnd_o1_04250_07750_both_wave_vs_tg_d.img_a05 &
fv meg_clnd_o1_07500_11000_both_wave_vs_tg_d.img_a05 &
fv meg_clnd_o1_10750_14250_both_wave_vs_tg_d.img_a05 &
fv meg_clnd_o1_14000_17500_both_wave_vs_tg_d.img_a05 &
fv meg_clnd_o1_17250_20750_both_wave_vs_tg_d.img_a05 &
fv meg_clnd_o1_20050_24000_both_wave_vs_tg_d.img_a05 &
For each (in fv) "Edit Image" and set the color-table to Hot, set plot to be log, set min to 0.001, max to 100 Also read in the Region File called
/data/oberon5/george/data/axaf/scripts/wave_vs_tg_d.img.reg
Then (for each image), "Print/Save-file" (to postscipt) called:
   meg_clnd_o1_01000_04500_both_wave_vs_tg_d.img_a05.ps
   meg_clnd_o1_04250_07750_both_wave_vs_tg_d.img_a05.ps
   meg_clnd_o1_07500_11000_both_wave_vs_tg_d.img_a05.ps
   meg_clnd_o1_10750_14250_both_wave_vs_tg_d.img_a05.ps
   meg_clnd_o1_14000_17500_both_wave_vs_tg_d.img_a05.ps
   meg_clnd_o1_17250_20750_both_wave_vs_tg_d.img_a05.ps
   meg_clnd_o1_20050_24000_both_wave_vs_tg_d.img_a05.ps
VISUAL CHECK: What we expect to see here is either (i) a 'nice', narrow, symmetric band centred at 0 (zero) tg_d (the y-axis), if the underlying spectrum of the target is dominated by continuum emission, (ii) a narrow row of bright-spots centred at 0 (zero) tg_d (the y-axis), if the underlying spectrum of the target is dominated by emission lines, or (iii) some combination of the two. HOWEVER it is also possible that there will appear to be nothing at all at tg_d=0 in one or more of the images (especially those covering the longer wavelength bands). This implies no photons at all were detected from the target at these wavebands, and does not necessarily mean there was an error in processing. We are also looking to see whether the background (everything on either side of tg_d=0) has any structure.

Finally convert the o/p files to jpgs (for later)

convert meg_clnd_o1_01000_04500_both_wave_vs_tg_d.img_a05.ps meg_clnd_o1_01000_04500_both_wave_vs_tg_d.img_a05.jpg
convert meg_clnd_o1_04250_07750_both_wave_vs_tg_d.img_a05.ps meg_clnd_o1_04250_07750_both_wave_vs_tg_d.img_a05.jpg
convert meg_clnd_o1_07500_11000_both_wave_vs_tg_d.img_a05.ps meg_clnd_o1_07500_11000_both_wave_vs_tg_d.img_a05.jpg
convert meg_clnd_o1_10750_14250_both_wave_vs_tg_d.img_a05.ps meg_clnd_o1_10750_14250_both_wave_vs_tg_d.img_a05.jpg
convert meg_clnd_o1_14000_17500_both_wave_vs_tg_d.img_a05.ps meg_clnd_o1_14000_17500_both_wave_vs_tg_d.img_a05.jpg
convert meg_clnd_o1_17250_20750_both_wave_vs_tg_d.img_a05.ps meg_clnd_o1_17250_20750_both_wave_vs_tg_d.img_a05.jpg
convert meg_clnd_o1_20050_24000_both_wave_vs_tg_d.img_a05.ps meg_clnd_o1_20050_24000_both_wave_vs_tg_d.img_a05.jpg

Cross-dispersion Histograms

Make histograms of the number of counts vs the cross-dispersion direction
fhisto meg_clnd.evts clobber=yes lowval=-0.01 highval=0.01 binsz=0.0001 column=tg_d outfile=meg_clnd.evts.tgd_hist0001
fhisto heg_clnd.evts clobber=yes lowval=-0.01 highval=0.01 binsz=0.0001 column=tg_d outfile=heg_clnd.evts.tgd_hist0001
These can now be plotted using the FTOOL fplot, which makes use of the QDP plotting package (see also Quick Guide). .
fplot meg_clnd.evts.tgd_hist0001 xparm = X yparm = Y rows ="-" device = "/XW" pltcmd =p
fplot heg_clnd.evts.tgd_hist0001 xparm = X yparm = Y rows ="-" device = "/XW" pltcmd =p
VISUAL CHECK: What we expect to see here is a 'nice', narrow, symmetric peak centred at 0 (zero) tg_d (the x-axis). We are also looking to see whether the background (everything except the peak) is well behaved (flat, as far as one can tell given the limited signal-to-noise). Don't be concerned if the background appears to cut-off (go to zero) at the edges of the plot.

Possibly More Steps to Come...


Onto the Next Step


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