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linespec



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

.ls linefile ""
Filename with list of emission or absorption lines in the format
.br
	Center wavelength of line in Angstroms
.br
	Half-width of line:  in Angstroms if positive,
.br
			     in km/sec if negative
.br
	Height of line in counts (this is arbitrary)
.br
	Name of line
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.ls linedir ""
Directory for line list (null string means current directory)
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.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.
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.ls maxwidth no
Use maximum of line or instrument width (yes) or convolve instrument with
spectrum (no).
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.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
velocity.
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.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. 
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.ls specobj = ""
Title for output spectrum
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.ls specfile = ""
File name for output spectrum
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.ls specdir = ""
Directory for output spectrum (null string means current directory)
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.ls st_lambda = INDEF
Starting wavelength in angstroms for output file
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.ls end_lambda = INDEF
Ending wavelength in angstroms for output file
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.ls pix_lambda 0.25,
Wavelength per pixel in Angstroms
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.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.
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.ls spec_int no
If yes, interact with the graph of the output spectrum
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.ls device = "stdgraph"
Interactive device on which to display a graphic summary of XCSAO's results.
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.ls plotter = "stdplot"
Second, non-interactive device on which to plot the graphic summary of results.
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.ls verbose yes 
     Print summary to log file (yes or not).
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.ls logfiles = "STDOUT,linespec.log"
All results from LINTEMP are recorded in these files.
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.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.
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.ls cursor = ""
Graphics cursor input.  When null the standard cursor is used otherwise
the specified file is used.
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DESCRIPTION
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.
 
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CURSOR
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 ":.help"):

.ls @
Make a hard copy on the device designated by \fIplotter\fR.
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.ls c
Prints cursor position in x and y.  This is the default.  All other
undefined keys perform this same function.
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.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.
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.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.
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.ls q
Quit and exit.
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.ls r
Forces a replot of the current spectrum at the original scale.
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.ls u
Redisplay the entire plot after zooming.
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.ls z
Zoom in on the region marked by two successive <z>'s
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EXAMPLE
To make a emission line template from a list of commonly observed
emission lines:

        cl> linespec emtemp.dat emtemp
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SEE ALSO
On-line help is available over the World Wide Web at
http://tdc-www.harvard.edu/iraf/rvsao/linespec
.endhelp

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