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4. Hard X-Ray Telescope (HXT)

4.1 Routines for Making Time Plots

4.1.1 PLOTT_HDA

PLOTT_HDA will make a light curve plot of all four channels using either the index or roadmap. The second `T' signifies that it is a time plotting routine. Four plots are made on the page, one for each channel. Some sample calls are:
IDL > plott_hda, index

IDL > plott_hda, roadmap

IDL > plott_hda, roadmap(100:200), psym=10

4.2 Routines for 2-D Spectral Display

4.2.1 DISP_HDA

The evolution of sensor intensity against time can be displayed as a pseudo-image using the routine DISP_HDA. Note: The time axis of DISP_HDA is not uniform.
IDL > disp_hda, index, data

4.3 Routines for Data and Information Extraction

4.3.1 GT_SUM_L

These routines will extract the average counts/sec of all 64 sensors. The input can be roadmap, index, or observing log and it will get the proper structure tag and decompress it properly to return counts/sec/sensor. It is possible to get a string defining the channel selected by using the title keyword option.
IDL > y = gt_sum_l(roadmap)

IDL > y = gt_sum_l(w_h, title=title)

4.3.2 GET_INFO

See the description in the ``General Yohkoh Software'' chapter on page 2.4.5.

4.4 Routines for Calibration and Analysis

4.4.1 HXT_QLOOK

HXT_QLOOK makes a series of HXT quick-look images (i.e. a quick-look movie). This program is much faster than the MEM code, but should be used only for quick-look movies. It is very useful for verifying positions etc. before running a long MEM job.
IDL > hxt_qlook, index, data, movie, hxi_index

IDL > hxt_qlook, index, data, movie, hxi_index, patterns

index HXT index from an HDA file
data HXT data from an HDA file
patterns the sub-collimator modulation patterns. Computed if not
supplied. The computation is slow, so if you plan to make
a series of movies, use patterns to receive the computed
patterns the first time you call HXT_QLOOK and then use
patterns to pass the modulation patterns back to the routine
on subsequent calls to HXT_QLOOK. You must recompute the
modulation patterns whenever you use a different pointing.

movie
a data cube of the HXT images (output)
hxi_index an index describing various parameters of the images. The
time in the index is the start of the accumulation period
(output).

/new_mod_patterns
Force a new computation of the modulation patterns,
even if the patterns parameter is set. Normally, if
patterns is set, the modulation patterns are not
computed. You must recompute the modulation
patterns whenever you use a different pointing.
/show_images show each image as it is computed
/quiet don't print any diagnostics
/verbose print lots of diagnostics
smooth smoothing parameter which determines how much the inverse
computation of the image is smoothed. Default = 0.1.

4.4.2 HXTPRO

See the User's Guide for a description of this program.

4.4.3 HXT_IMG

See the User's Guide for a description of this program.

4.4.4 GET_HXT_POS

The routine GET_HXT_POS will return the HXT address of the flare location. It will perform the following checks in this order until it finds a match.

Read the $DIR_HXT_CAL/hxt_flare_pos.txt file to see if the time is in that list
Use the GOES heliocentric location to determine the address
Use an SXT image index to define the address
Pass in heliocentric coordinates and convert them
Ask for user to specify HXT address directly

Sample calls are:
IDL > xy0 = get_hxt_pos('15-Nov-91 22:37')

IDL > xy0 = get_hxt_pos(index(20), helio='N32W23')

IDL > xy0 = get_hxt_pos(index(20), status=status)
The optional keywords /get_sxt, /get_goes and helio will force the calculation of the function to use that technique. The keyword option /nouser should be used when running in batch mode as it will inhibit asking the user for input. The status output is a -1 if no match has been found, 1 for HXT flare list, 2 for SXT image, 3 for GOES event list, 4 for heliocentric coordinate passed in, and 5 for user input.

4.4.5 HXT_FSP and HXTBOX_FSP [*]

HXT_FSP is the same as HXS_FSP, but for HXT spectra. See HXS_FSP for a better description. Index and data come from an hda file.
IDL > HXT_FSP, index, data, fit_pars
HXTBOX_FSP fits spectra to a given box, chosen by LCUR_IMAGE, for a set of HXT images in the HXI structure; index and data come from and hxi file of deconvolved images.
IDL > HXTBOX_FSP, index, data, fit_pars

4.4.6 SXTHXT_FSP and SXTHXTBOX_FSP[*]

SXTHXT_FSP fits combination SXT and HXT spectra, no spatial resolution! index and data are uncompressed SXT images, hindex and hdata are uncompressed HXT data, from an HDA file.
IDL > SXTHXT_FSP, index, data, hindex, hdata, fit_pars
SXTHXTBOX_FSP fits SXT-HXT spectra for a box chosen using LCUR_IMAGE. hindex must be the HXI structure, and hdata are HXT images. You should be sure of alignment beforehand.
IDL > SXTHXTBOX_FSP, index, data, hindex, hdata, fit_pars

4.4.7 HXT_DECOMP

HXT_DECOMP will decompress the HXT data. A sample call is
IDL > odata = hxt_decomp(data)

index	HXT index from an HDA file
data	HXT data from an HDA file
patterns	the sub-collimator modulation patterns. Computed if not
supplied. The computation is slow, so if you plan to make
a series of movies, use patterns to receive the computed
patterns the first time you call HXT_QLOOK and then use
patterns to pass the modulation patterns back to the routine
on subsequent calls to HXT_QLOOK. You must recompute the
modulation patterns whenever you use a different pointing.
movie	a data cube of the HXT images (output)
hxi_index	an index describing various parameters of the images. The
time in the index is the start of the accumulation period
(output).
/new_mod_patterns	Force a new computation of the modulation patterns,
even if the patterns parameter is set. Normally, if
patterns is set, the modulation patterns are not
computed. You must recompute the modulation
patterns whenever you use a different pointing.
/show_images	show each image as it is computed
/quiet	don't print any diagnostics
/verbose	print lots of diagnostics
smooth	smoothing parameter which determines how much the inverse
computation of the image is smoothed. Default = 0.1.