23.1 Data Reduction Applications

• toolbox.imgtools.mstools: Contains image manipulation tasks created especially for STIS and NICMOS image set (imset) data and which exploit the error and data quality arrays in their operations (e.g., msarith, mscombine, msstatistics, mssplit, and msjoin). These tasks are described in "Working with STIS and NICMOS Imsets" on page 3-12.
• hst_calib.stis: Contains the STIS specific tasks basic2d, calstis, ocrreject, wavecal, x1d, and x2d. In addition to the above packages, most basic image manipulation software (e.g., display, daophot, imexamine, contour, etc.) and spectral analysis software (e.g., splot, tables, specfit, igi, etc.) available in IRAF/STSDAS can be used on STIS data, either directly through the IRAF FITS interface or by converting data to another IRAF format. Chapter 3 includes information about how to display STIS images and extracted spectra as well as how and when to convert data formats and a description of spectral analysis taks. Table 23.1 lists some of the more useful IRAF/STSDAS applications for working with STIS data.

  Spectral Analysis Tasks

  Task	Input Formats	Purpose
  echplot	3-D tables	Plots multiple STIS echelle spectral orders.
  nfit1d	2-D & 3-D tables, images	General 1-D feature fitting; part of the STSDAS fitting package.
  igi	2-D & 3-D tables, images	General presentation graphics; supports world coordinates.
  sgraph	2-D & 3-D tables, images	General 1-D plotting; supports world coordinates.
  specfit	1-D images, ASCII tables	General 1-D spectrum modeling package.
  splot	multispec images	General 1-D spectral analysis.

  Some of the tasks are intended for browsing data or producing publication-quality plots: the igi and sgraph tasks were described in Chapter 3. The echplot task is useful for browsing STIS extracted spectra. You can plot single spectral orders, overplot multiple orders on a single plot, or plot up to 4 orders in separate panels on the same page. For example, we overplot the orders contained in rows 2 through 4 and 6 on one page:

cl> echplot "stis_x1d.fits[1][r:row=(2:4,6)]" output.igi \

>>> plot_style=m