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.help linespec Aug99 rvsao
linespec -- Make a spectrum from a list of emission and/or absorption lines
linespec linefile specfile

.ls linefile ""
Filename with list of emission or absorption lines in the format
	Center wavelength of line in Angstroms
	Half-width of line:  in Angstroms if positive,
			     in km/sec if negative
	Height of line in counts (this is arbitrary)
	Name of line
.ls linedir ""
Directory for line list (null string means current directory)
.ls linewidth 2.0
Half-width at half-max of Gaussian emission lines in Angstroms
This instrumental function is convolved with the spectrum from linefile.
.ls maxwidth no
Use maximum of line or instrument width (yes) or convolve instrument with
spectrum (no).
.ls zspec 0
Delta lambda / lambda to which to shift individual spectral lines. This
is useful for making spectra for very distant objects and supercedes
velspec if it is not zero. 
.ls velspec 0
If this is not zero, shift the wavelengths of all specified lines to this
.ls continuum 0 
Continuum level for output spectrum. This is useful if software to be
used on the created spectrum has problems with a continuum of zero or
absorption lines with negative nadirs. 
.ls specobj = ""
Title for output spectrum
.ls specfile = ""
File name for output spectrum
.ls specdir = ""
Directory for output spectrum (null string means current directory)
.ls st_lambda = INDEF
Starting wavelength in angstroms for output file
.ls end_lambda = INDEF
Ending wavelength in angstroms for output file
.ls pix_lambda 0.25,
Wavelength per pixel in Angstroms
.ls spec_plot = yes
If yes, a plot of the output spectrum is displayed.
Cursor commands are activated for zooming in on a portion of the
spectrum and hard copies may be made to stdplot using the \fI@\fR command.
If maxwidth is no, the spectrum is displayed both before and after it is
convolved with the instrumental Gaussian.
.ls spec_int no
If yes, interact with the graph of the output spectrum
.ls device = "stdgraph"
Interactive device on which to display a graphic summary of XCSAO's results.
.ls plotter = "stdplot"
Second, non-interactive device on which to plot the graphic summary of results.
.ls verbose yes 
     Print summary to log file (yes or not).
.ls logfiles = "STDOUT,linespec.log"
All results from LINTEMP are recorded in these files.
.ls debug = no
If yes, values of the parameters fit to the selected peak
are recorded in the log files.  This is most useful for debugging.
.ls cursor = ""
Graphics cursor input.  When null the standard cursor is used otherwise
the specified file is used.
LINESPEC reads a list of positions of emission and/or absorptions lines
and creates a spectrum with Gaussian lines of the the indicated
half-widths at the indicated positions, writing a one-dimensional IRAF
file with the appropriate keywords in the header.  If velspec is nonzero,
the emission lines are shifted to that redshift velocity.
The following keystrokes are active for spectrum template plots in addition
to the normal IRAF cursor facilities (a list of those is available with
the command ""):

.ls @
Make a hard copy on the device designated by \fIplotter\fR.
.ls c
Prints cursor position in x and y.  This is the default.  All other
undefined keys perform this same function.
.ls d
Replaces a region between the marked vertical cursors with interpolated
values from the edges of the marked region.  This is can be used to eliminate
lines from a template without changing the line list, though the line will
still appear in the image header.
.ls n
Smooth spectrum n times before plotting.  This affects the actual spectrum,
so it is usually not a good idea to exit from a plot with this set to any
value other than 0.
.ls q
Quit and exit.
.ls r
Forces a replot of the current spectrum at the original scale.
.ls u
Redisplay the entire plot after zooming.
.ls z
Zoom in on the region marked by two successive <z>'s

To make a emission line template from a list of commonly observed
emission lines:

        cl> linespec emtemp.dat emtemp
On-line help is available over the World Wide Web at

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