List of file names of spectra to analyze.
@filename indicates list should come from file filename.
As of version 1.3, apertures of multispec spectrum files can be entered as
numbers, lists, or ranges enclosed in brackets after each file name in
the list or file.
If this is nonzero and spectra contains a single file name, this is
a range of apertures in a multispec file which will be cross-correlated.
This number is ignored if a spectrum number is specified using
brackets. Wavelength dispersion information is read from APNUMn or
the WCS keywords. Velocity information is read from APVELn and saved in
APVELn and APVXCn.
If this is nonzero, it is the band in the multispec file(s) specified by
spectra which will be cross-correlated.
Wavelength dispersion information is read from APNUMn, where n
is the aperture specified by specnum or the WCS
keywords. Velocity information is read from APVELn and saved in
APVELn and APVXCn.
(New in version 2.0)
Directory containing spectrum to be analyzed. This part of the
pathname is not printed at the top of the page, and is assumed to be
the same for all spectra listed in the spectra parameter.
If yes, cross-correlate object spectrum against specified template
spectrum, displaying spectrum, correlation peak (if display mode 1),
and detailed results for the best 12 templates.
If no, display spectrum with previous results read from the spectrum image
header with no correlation peak plot.
Template file or comma-separated list of file names of images to use
as templates or name of file containing template file names, one per line.
As of version 1.3, apertures of multispec template files can be entered as
numbers, lists, or ranges enclosed in brackets after each file name in
the list or file. As of version 2.2, wavelength (or pixel) ranges of
templates to be correlated can be specifies as :w1-w2 (:p1-p2) appended
to the template name. Multiple pieces of a single template spectrum
can thus be correlated agains multiple pieces of an object spectrum.
If nonzero and templates contains a single file name, this is a range
of spectrum numbers in a multispec file to be used as templates.
Wavelength dispersion information is read from APNUMn, and velocity
information is read from APVELn. This number is ignored if a spectrum
number is specified using brackets.
If this is nonzero, it is the band in the multispec file(s) specified by
templates which will be cross-correlated.
Wavelength dispersion information is read from APNUMn, where n
is the aperture specified by tempnum or the WCS
keywords. Velocity information is read from APVELn.
(New in version 2.0)
If yes, the spectrum is assumed to be a multispec file containing
multiple orders. The range of spectrum numbers (which may not have the
same numbers as the echelle orders) defined by specnum, or within
brackets following the spectrum file name, is used for the template rather
than the range defined in tempnum, or withing brackets following
template file names.
If yes, a plot of the object spectrum is displayed. During this time the
normal IRAF cursor commands are active as well as several more that are
itemized below.A If emission lines are chopped, before and after plots
are displayed, as well as the chopped line(s).
If yes, a plot of the filtered cross-correlation function is displayed.
Cursor commands are activated, and a peak other than the maximum
can be chosen to be the center with the keystroke p. Hard copies
to stdplot may also be made using the @ command.
File containing list of starting and stopping wavelengths in Angstroms for
removal of portions of all object spectra if
fixbad is yes. All information after the
second wavelength is a comment field. This file is assumed to be in the
directory linedir unless a complete pathname
starting with "/" is specified. (added in version 2.0)
If "yes", emission lines are removed from the object spectrum before
cross-correlating. If "no", they aren't. If "specfile", the flag
CHOPEM in the object spectrum header causes emission lines in the
object spectrum to chopped if true. If "tempfile", the flag CHOPEM
in the template header causes emission lines in the spectrum to be removed
before the correlation is done. If the EMCHOP header parameter
in the spectrum image header is set to T, the emission lines are assumed
to have been removed already, and no additional removal is done.
If "yes", emission lines are removed from the template spectrum before
cross-correlating. If "no", they aren't. If "specfile", the flag
CHOPEM in the object spectrum header causes emission lines in the
template spectrum to chopped if true. If "tempfile", the flag CHOPEM
in the template header causes emission lines in the template spectrum to be
removed before the correlation is done. If the EMCHOP header parameter
in the template image header is set to T, the emission lines are assumed
to have been removed already, and no additional removal is done.
If yes, emission lines are removed from the spectrum before
cross-correlating.
A fraction bell_window of the ends of the object and template spectrum are
multiplied by a cosine bell. This is to reduce high wave number Fourier
components that would be produced by abrupt cutoffs at the ends of the spectra.
If true, the data spectrum is divided by its mean value before being
transformed. The minimum value (divided by the mean first) is then
subtracted, and the whole thing is multiplied by an arbitrary factor of
1000.0 to put it within normal count levels. This is used on spectra
which may have unusual values if they have already been flux-calibrated.
Pad transforms with zeroes to lower noise (yes, no, tempfile). If
tempfile, read T or F from ZEROPAD template header
parameter to zero-pad or not zero-pad, respectively.
The Fourier amplitudes are multiplied by a cosine-bell filter function,
starting at low_bin and running to nrun.
Values chosen for low_bin and nrun are not critical.
Generally low_bin should be about 5 to 10 for a 1024 point
spectrum of 2-4 pixel resolution.
Set nrun based upon the number of points in your spectrum and
the resolution.
For a spectrum of NPTS pixels and resolution FWHM,
nrun ~ NTPS / (2*PI * FWHM/2.355).
Tonry and Davis 1979, A.J., 84, 1511).
Make an inital velocity guess. It is used to shift the template in
wavelength to give a better overlap region. The options are: zero
to use no initial velocity,
guess to use czguess in cz (km/sec),
zguess to use czguess in z (delta lambda / lambda),
correlation to use the correlation velocity in the spectrum
header parameter CZXC, emission to use the emission line
velocity in the spectrum header parameter CZEM, and
combination to use the velocity in the spectrum header parameter
VELOCITY.
Night to night velocity zero point shift. If this is zero, each template
spectrum header is checked for a TSHIFT parameter, and that is used if
present.
Spectrum velocity correction to the solar system barycenter. Set to
"none" if spectrum has already been shifted or if this correction is
unnecessary. If "file", BCV is used if present in the file header,
or else HCV. If "hfile", the header parameter HCV is always
used. If neither is found, no correction is made. If "heliocentric"
or "barycentric" corrections are chosen, position and time parameters
are read from the spectrum data file header. DATE-OBS (date in
FITS format 'yyyy-mm-dd' or 'dd/mm/yy' before 2000),
UTEND (U.T. at end of exposure as 'hh:mm:ss')
and UTOPEN or UT (U.T. at start of exposure as 'hh:mm:ss') or
EXPOSURE (length of exposure in seconds) are used to compute
the midtime of the exposure. RA (right ascension as 'hh:mm:ss.ss'),
DEC (declination as 'dd:mm:ss.ss'), and EPOCH (epoch of
coordinates defaults to 1950.0) give the position of the object whose
spectrum this is. SITELONG (observatory longitude as 'dd:mm:ss.ss'
or degrees), SITELAT (observatory latitude as 'dd:mm:ss.ss' or
degrees), and SITEELEV (observatory altitude in meters) give the
observatory position.
Template velocity correction. Set to "none" if template is already
corrected to "heliocentric", else "heliocentric", "barycentric", or
"file". If "file", BCV is used if present in header, else HCV.
VELOCITY in the template file header is assumed to be the barycentric
corrected velocity. If the spectrum is unshifted, this correction must
be made; if the spectrum has been shifted, this should be "none" and the
BCV parameter in the template header should be 0. If "barycentric" or
"heliocentric", the same parameters as above must be present in the template
file header.
Flag for peak fitting: 1=parabola, 2=quartic, 3=cos/(1+x^2)
These are usually equivalent, but the quartic works better for broad,
flatter-topped peaks. The cos/(1+x^2) function works best on very
high signal-to-noise correlations which can be fit down to the base of
the correlation peak.
Fraction of peak or number of points for peak fitting.
If negated, the points used in the fit will be marked in the final
display. (option added in 1.8)
When a correlation peak is manually selected, the position used as the peak
is the maximum correlation value within this many bins of the cursor-selected
bin.
Includes filenames, R, velocity and error in km/sec, and height and
width of correlation peak.
=3 one line per spectrum giving best fit and previous results
Previous results are read from the image header and written alternately
with new results: file, old R, new R, old velocity, new velocity, old
error, new error, Julian date of observation, and name of best
template.
=5 one long line per spectrum-template combination.
Includes 4 filter parameters, template file name, tshift from template
header, spectrum filename, velocity, R value, peak height and width, and
heliocentric velocity correction.
=6 one long line per spectrum-template combination.
Includes spectrum and template names, Julian date, velocity, error,
R-value, correlation peak height and width, and velocity correction to
solar system barycenter
=7 one long line per spectrum-template combination.
prints per template results from current correlation and from
previous correlation as saved in the spectrum header. Includes
filename, old and new R-value, old and new velocity, old and new error,
old and new peak height, old and new ARMS, Julian date of observation,
and old and new template names.
Includes spectrum filename, instrument code, object name, Julian
date of observation, emission line velocity and error, correlation
velocity, error, and R-value, number of emission lines found and fit,
and the name of the template giving the highest R-value.
=9 one long line per spectrum-template combination.
Includes observatory code, spectrum filename, template filename,
Julian date of observation, velocity, error, and R-value, correlation
peak height and width, barycentric velocity correction. The sigma of
the spectrum transform, sigma of the template transform, and name of
the file containing the correlation vector for this spectrum-template
combination are added to the end of the line if such a file is written.
Includes spectrum filename, Julian date of observation, number of
best template in list, name of best template, velocity, error, and R-value
for best, and each template.
Includes spectrum filename, Julian date of observation, number of
best template in list, filename, velocity, error, and R-value for best
template, filename, velocity, error, and R-value for each template.
Includes spectrum filename, Julian date of observation, number of
best template in list, and filename, velocity, error, and R-value for
each template.
=13 one long line per spectrum-template combination.
Includes observatory code, spectrum filename, template filename,
Julian date of observation, velocity (from the searched, not fit, peak),
peak height and width, barycentric velocity correction. The sigma of
the spectrum transform, sigma of the template transform, and name of
the file containing the correlation vector for this spectrum-template
combination are added to the end of the line if such a file is written.
Includes spectrum filename, Julian date of observation, emission line
velocity, error, number of lines found, and number of lines fit,
number and name of best template in list, and filename, velocity, error,
and R-value for each template. (mode added in version 2.0)
=15
one long line per spectrum-template combination.
Includes spectrum and template names, Julian date, velocity, error,
R-value, correlation peak height and width, and velocity correction to
solar system barycenter. It is like mode 6, but with 2 more template name
characters and velocities to m/sec. (mode added in version 2.0.1)
=16
One long line per spectrum-template combination.
Includes spectrum and template names (24 and 16 characters, respectively),
R-value, radial velocity and error in km/sec, height of correlation peak,
template wavelength limits, and center wavelength of correlated template
spectrum. This is used with wide synthetic templates of which only portions
are used.
=17 one long line per spectrum-template combination for Hectochelle.
Includes aperture, fiber, beam, 24-character spectrum name, last 24
characters of template name, heliocentric Julian Day, radial velocity,
velocity error, R-value, correlation peak height and width, and barycentric
velocity correction.
=18 one long line per spectrum-template combination for Hectochelle.
Includes aperture, full spectrum pathname, full template name,
heliocentric Julian Day, radial velocity, velocity error, R-value, and
barycentric velocity correction.
Center velocity of the summary velocity correlation graph in km/sec.
This defaults to the velocity from the cross-correlation with the
highest R value.
Velocity half-width of the summary velocity correlation graph in km/sec.
This defaults to 20 times the width of the peak of the cross-correlation
with the highest R value.
Name of file containing an absorption line list. It is used if the "l"
cursor option is selected and either the "e" or "b" cursor command is used
to identify an emission line in the spectrum, or if display modes 2 or 3 are
used to display the data and an emission line fit has been done or an emission
line template gets an R value over 3.0. If the filename is preceded by a "+",
emission lines are always labelled.
Directory containing line list files named by
ablines,
emlines, and
badlines.
Filenames containing a "/" in the first column are assumed to be full
pathnames; if there is a "/" anywhere else in the filename, the path is
assumed to be relative to the current working directory.
If there is a "$" in the filename, the part preceding the "$" is assumed to
be an IRAF environment parameter defining a directory. In any of these
cases, the linedir parameter is ignored.
Format in which to display summary page on an interactive display
device and on the hard-copy device plotter. If the format
code is negated, the spectrum is plotted with the intensity scaled from
zero rather than the spectrum minimum.
=-1 Display all of spectrum,
with portion used marked, scaled from an intensity of zero, and
cross-correlation with template information.
=0 Display only part of spectrum
used in correlation and cross-correlation with template information. (2.0)
=1 Display all of spectrum,
with portion used marked, and cross-correlation with template information.
=2 Display spectrum with
absorption and known emission lines labelled and both template and
emission line information.
=3 Display spectrum with absorption and known emission lines labelled
using the entire display without the table of results
=4 Display continuum-subtracted spectrum with absorption and known
emission lines labelled and tables of template and emission line information.
=5 Display continuum-subtracted spectrum with absorption and known
emission lines labelled using the entire display without the table of results.
(3,4,5 added in version 2.1)
If yes, wait in cursor mode displaying correlation results after each
spectrum is processed. Many commands
are available, including changing which template is used for the
correlation peak and velocity displayed, switching display modes between
correlation peak and labelled lines, and rerunning the correlation with
manual peak selection or an edited spectrum. Cursor mode commands may be
listed by typing "?".
If yes, plots of the continuum-subtracted object and template spectra are
displayed. This is most useful for determining the appropriateness of
the order of the polynomial chosen to fit the continuum.
If yes, plots of the windowed object and template spectra are displayed.
This is most useful for determining the size of the cosine bell window
applied to either end of the spectrum.
If yes, the power spectrum of the transformed object data and template
is displayed.
This is useful for setting the low order cutoff for the filter and for seeing
if any periodic noise is present in the data.
If yes, the power spectrum of the transformed object and template data,
after filtering, is displayed. This lets the user see the data which is
actually being correlated.
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