RVSAO History

The RVSAO package was developed by Jessica Mink at the Harvard-Smithsonian Center for Astrophysics from the REDSHIFT package originally written by Gerard Kriss at Johns Hopkins University and modified significantly by Steve Levine while he was at the University of Wisconsin. The original package is still available as a contributed package in the IRAF STSDAS package.

RVSAO obtains radial velocities using cross-correlation methods or emission line fits. There are seven main tasks in the package: xcsao, emsao, sumspec, linespec, eqwidth, bcvcorr, listspec, and several supporting tasks.

2.8.5 March 15, 2022
Shell directory tasks updated to use IRAF2.17
Installation instructions updated to IRAF2.17

2.8.4 February 5, 2021
emsao: Save individual apertures/orders when they are changed
emfit.x,emplot.x,xcfit.x,xcplot.x: Pass spectrum, specim in common/rvspec/ so that emplot can write to file(s)
Shell directory tasks updated to use IRAF2.16.1

2.8.3 July 6, 2015
* All .com and .h files are in rvsao$lib only
bcvcorr: Fix bug keeping JD from parameter file
Initialize savespec to FALSE in emsao and pemsao.
Fix listspec bug so appropriately-named file is written if requested

xcplot.x: Set qplot=TRUE if spectrum is edited

2.8.2 June 13, 2014
Edit cosmic rays out of a spectrum by resetting a point at a time
(using the , key) or by linearly interpolating between points on
either side of a cosmic ray (using the d key twice). The edited
spectrum is automatically written out if you are running qplot or
are saving information to the spectrum header and leave with "q".
xcsao, emsao,pxcsao,pemsao: Write back edited spectrum

xcfit.x: Call putspec to update spectrum after editing it (2014-05-02)
emplot.x: Fix bug which reversed red and blue limits (2013-03-15)
emplot.x: Add , command to replace individual pixel values (2014-05-01)
emplot.x: Add > command to write out edited spectrum (2014-05-02)
t_eqwidth.x: Drop declaration of results.com; it's not used

2.8.1 May 25, 2012
Add maxlength parameter to pxcsao to set output spectrum file length in mode 11

xcrslts.x: add parameter maxlength to allow longer filename in mode 11

2.8.0 April 13, 2012
in listspec, add velform format for velocity per pixel output
Add skyplot based on pemsao instead of xcsao, like emplot
Add new shell script rvsaopar to set RVSAO task parameters from a dpar file
Add new shell script pxcsao to execute SPP pxcsao IRAF task

juldate.x: Do not recompute HJD if already in header
juldate.x: Check for BJD as well as HJD
vcombine.x: Do not add constant dispersion error of 15 km/sec any more
xcfile.x: Only include file name in xc file if given full pathname
xcfile.x: Drop ".ms.fits" and ".fits" from object and template filenames
xcfile.x: Add ".xcor" file extension to output filename
Fix bug in xcfile.x by redimensioning title from SZ_LINE to SZ_PATHNAME

2.7.9 August 11, 2010
In pemsao write median (MEDPIX) and mean (MEANPIX) pixel shift to image header
In pemsao do not write back to parameter file if save_vel=yes
Skip apertures in pemsao where no lines are found for means and medians
Set FITS extension in pemsao and pxcsao with specext keyword
Initialize all pointers in pxcsao and xcsao to NULL; free only if not NULL

xcfit.x: Return properly if there is an error reading a spectrum
getspec.x: Return error if spectrum has no non-zero pixels
getimage.x: If stacked spectra and CD2_2 is not set, set it to 1
getimage.x: Always add extension to file name, even if it is zero

2.7.8 November 20, 2009
Zoom and line identification changes in xcsao, pxcsao, emsao, and pemsao from changes in emplot.x
Increase image string size in listspec, pix2wl, and wl2pix to SZ_PATHNAME(511) from SZ_FNAME(255)

emplot.x: Fix zoom at left and right edges of a displayed spectrum.
Replot immediately with new velocity if line selected
Mark VELOCITY as being used if it is guessed from a line
Change to correlation velocity automatically if switching templates
getimage.x: Increase image string size to SZ_PATHNAME(511) from SZ_FNAME(255)

2.7.7 July 28, 2009
If DIVCONT in xcsao is T in object spectrum, divide it by its continuum and subtract 1.0 instead of subtracting the continuum; do the same with all templates, if they have no SUBCONT flag.
Increase maximum number of points in xcsao and pxcsao peak fit from 512 to 1024 for TRES
If contspec.order is zero, do not remove continuum in xcsao and emsao
If dividing continuum in xcsao, emsao, or sumspec, normalize by mean of continuum to get the true variation in count rates.
Compute sigma in eqwidth according to John Huchra's new formula

2.7.6 June 15, 2009
wlrange is a new task to return the overlapping wavelength range for a list of spectra

2.7.5 June 10, 2009
Major changes in eqwidth to make it more robust and handle rest wavelengths correctly.
Fix multiple aperture in emsao and pemsao plotting so it doesn't crash or print blank lines
Compute lambda/pix in pemsao by offset from line center to avoid dividing by zero if line is exactly at rest wavelength (as for a sky or calibration lamp line)
Fix bugs in sumspec so that rebinned wavelength range can be computed from overlap

emrslts.x: Return immediately if no log file is set
emplot.x: Get number of apertures from im structure, not smw
emlines.dat: Add Lyman Beta and Gamma; move Lyamn Alpha from 1215.7 to 1215.67
Fix name of 1240.0 from LyA to NV

2.7.4 April 24, 2009
Add SUBGRAV parameter to bcvcorr to make solar gravitational redshift subtraction from twilight sky spectra optional
Allow multiple apertures in listspec and write them to separate files
In eqwidth, fix error computation for equivalent widths and indices
Handle spectra in sumspec with PIXEL WCS correctly

getimage.x: Set RA, DEC, ST, HA to 0:00 if not in header [for shdr_open()]
juldate.x: Add MJD as possible JD header keyword; return hjd = jd if there is no pointing direction in the image header

2.7.3 March 31, 2009
Add new shell scripts in rvsao$Shell/ to run most RVSAO tasks on the Unix/Linux command line.

2.7.2 March 13, 2009
In xcsao, add option to shift orders when cross-correlating echelle spectra.

2.7.1 February 20, 2009
In emsao and xcsao assume RA is in degrees if decimal keyword value, not hours

2.7.0 January 30, 2009
In sumspec, fix bug which put back heliocentric velocity correction when shifting to a specific velocity and delete IRAF WCS keywords if one spectrum is being rebinned.
Fix error of index in eqwidth so that it is at least closer to correct. Fix bug so that a lack of a VELOCITY or BCV keyword does not crash the program. Clean up exposure scaling.

2.6.9 December 9, 2008
In eqwidth, correctly compute Index and Index Error; Set to 0.0 if no continuum
Plot line name and wavelength in emsao and emplot if only labeling emission lines
Add emlineshe2.dat He2 line list

2.6.8 October 7, 2008
) and ( commands were added to emsao and emplot to move through orders or apertures.

2.6.7 September 16, 2008
rvrelearn is a new task to relearn all of the parameters from all of the tasks in RVSAO. Old parameters keep their values; new parameters will be assigned default values.
In sumspec, pointing direction is kept if numbers of input and output apertures are the same.

2.6.6 August 12, 2008
In pemsao set median and quartile velocity shift, plus mean and median pixel and wavelength shift parameters for multiple aperture computations.
pix2wl is a new task to return wavelength at a specified pixel in a spectrum or if the pixel value is zero, the range in wavelength covered by the image.
wl2pix is a new task to return the pixel of a wavelength in a spectrum specified in Angstroms.

xcmin.x Check for divide by zero in this correlation peak fitting program to avoid crashes in xcsao and pxcsao.

2.6.5 July 8, 2008
In eqwidth, error computation and 3 additional reporting modes were added. A bandfilt parameter was added to indicate whether filter columns are included in the band file bandcont was added to indicate whether continuum names are present, and banddir was added to specify a directory for the band file.
Three new tasks were added to plot spectra: emplot plots spectra and labels lines, skyplot plots sky spectra and labels emission lines, and xcplot plots spectra without cross-correlating, acting as a simpler splot.
Transform filtering in xcsao and pxcsao was fixed so that zero-padded spectra really are unfiltered. The toplo, topnrun, and nrun numbers are now doubled when zeropad=yes, as they should have been all along.
In xcsao, pxcsao, and sumspec, an old bug with log wavelength SUMS rebinning was fixed. Bad velocities were possible if using log-wavelength templates which were not created using SUMS rebinning.
xcsao, pxcsao, emsao, and pemsao results printing subroutines were fixed so they have fewer string constants and will compile on Solaris IRAF.

getimage.x: Fix recent bug which caused problems if file name extensions assumed
rebin.x: Compute edges of pixels for SUMS log wavelength rebinning in rebinl()

CL scripts have been moved into the Scripts/ subdirectory.
Shell scripts have been moved into the Shell/ subdirectory and suffixes dropped.

2.6.4 May 9, 2008
In xcsao, pxcsao, emsao, pemsao, and sumspec, if bad line file line name starts with "pix", assume that the limits in the previous two columns are given in pixels instead of wavelength, and interpolate between the spectrum values at those two wavelengths to eliminate bright emission lines.
In xcsao and pxcsao, if removing bad lines between pixel limits, do the same for template(s); normally only the object spectrum is fixed.
In xcsao and pxcsao, if SUBCONT=F in the object header, the continuum is not removed.
In pxcsao, save median and quartile velocities as parameters for echelle.
In emsao and pemsao, if wavelength limit parameters are negative go in the absolute value of that many Angstroms from the appropriate end of the spectrum. Save mean velocity to meanvel parameter and error to meanerr parameter
In emsao and pemsao, increase maximum number of emission lines to 500 (for multi-order ThAr spectra) and combination emisson line sets from 5 to 20.
In sumspec, add missing argument in addspec() call to filllist()
Add listspec, a new task to print spectra in a variety of formats.
2.6.3 February 11, 2008
Increase the maximum number of templates to 3000 in xcsao and pxcsao,
Add report mode 18 for TRES results to xcsao and pxcsao.
2.6.2 January 14, 2008
Fix bug sumspec so spectra can be added again.
Save mean velocity shift of apertures (=orders) in pxcsao if echelle=yes

2.6.1 October 15, 2007
Fix boolean check in writetemp.x so sumspec compiles on MacIntel
Fix boolean check in xcplot.x so xcsao compiles on MacIntel

2.6.0 September 3, 2007
Add new task pxcsao to write best template, velocity, error, and r-value to its parameter file for use in CL scripts.
Add new task pemsao to write number of lines fit, velocity, error, height, width, and equivalent width of the first emission line in its list to the parameter file for use in CL scripts.
In xcsao and pxcsao, drop all cache pointers from xcfit.x and rvsao.com. Add xplt.com containing pointers for plotting buffers in xcplot.x and xcorplot.x. They are allocated to the maximum size needed and freed at the end of t_xcsao.x and t_pxcsao.x.
Fix dropped line in xcfit.x so qplot works again.
Drop excess commas from prompt for parameter savejd in bcvcorr.par so bcvcorr works.

2.5.9 June 21, 2007
Allocate all transform vectors in xcsao so number of bins is unlimited
In bcvcorr, add printmode, returned bcv and hcv parameters, and savejd to separate saving of date and velocity (savebcv) information in image header.

2.5.8 June 14, 2007
In getimage.x, read RA and DEC as strings, not numbers if APIDi is present.

2.5.7 April 6, 2007
Print last 27 characters of template in xcsao report mode 17 (-.fits)
Print object name in xcsao as "filename_aperture", not "filename [aperture]".
Fix bug in emsao which caused line finding to fail if wavelength increased left to right.
Fix exposure time addition bug in sumspec

2.5.6 February 14, 2007 SUMSPEC: Preserve APNUMi keywords when linearizing multi-aperture multispec image

2.5.5 February 1, 2007
Plot all emission lines, if any are specified, in emsao and xcsao not just those which were found.
Do not modify data structure in xcsao when dropping leading and trailing zeroes.
Fix bug in xcsao which caused wavelength range to shrink spontaneously.
In qplot, xcsao, and emsao, always label lines after identifying one.
In qplot, xcsao, andemsao, add 'l' option to 's' option to set velocity from identified line with an automatic error of 300 km/sec to avoid having to type in the numbers.
In qplot and xcsao, re-cross-correlate using velocity of identified line as guess on 'f'.

2.5.4 October 24, 2006
Increase maximum number of templates in xcsao from 256 to 512 (rvsao.h).

2.5.3 September 27, 2006
Fix normalization bug in xcsao to now divide by mean *before* adding floor.

2.5.2 August 17, 2006
In xcsao, do not use pixels at either end of spectrum with values of zero

2.5.1 July 13, 2006
In xcsao and emsao do not read per-aperture info for apertures > 999.

2.5.0 June 1, 2006
In xcsao, add report mode 17 for Hectochelle.
Extract object name and coordinates from APIDi keywords for multispec files, so individual object spectra can be correlated or have their emission lines fit correctly.

2.4.9 May 19, 2006
In xcsao, rename the rcomp() subroutine to rcompx() in xcplot.x and fix bug in xcwhead() so header comment documenting template entries works. In emsao, rename the rcomp() subroutine to rcompe() in emplot.x. In sumspec, keep all-zero spectra (continuum fit and spectrum - continuum are all zeroes, too).

2.4.8 March 9, 2006
Major changes have been made to bcvcorr. A new parameter specsun to use the direction of the sun instead of the pointing direction if yes (for twilight sky spectra). Another paramter was added to indicate when the specified time is relative to the observation You must run relearn bcvcorr to add the new parameters. UT is now decoded from a FITS DATE-OBS keyword value if it is there, and JD- and MJD-containing keywords can now specify the observation time, too. In xcsao, two wavelength structures which are allocated for every spectrum are now freed, eliminating a cause of memory overflows when processing many spectra in a loop. In xcsao and emsao, add ZERR z error to the output file header. In xcsao and emsao, fix rcomp() declaration error in xcplot.c and emplot.c. In emsao, make sure all displays of z and 1+z are labelled correctly. In sumspec, always set output BCV to 0.0; it is always corrected for.

2.4.7 December 9, 2005
In eqwidth, fix bug when computing flux with a fit continuum. In xcsao and emsao, force renormalization if -1 < spectrum < 1, not if max < 1. In getimage.x, do not append aperture to name if =0.

2.4.6 August 22, 2005
Print ZXC, ZEM, and Z in header in xcsao and emsao.

2.4.5 July 28, 2005
In eqwidth, print multiple output streams and print zeroes if no flux or offscale.

2.4.4 July 14, 2005
Fix two erroneous calls to mfree() in emsao which worked OK in Solaris, not Linux

2.4.3 May 25, 2005
In emsao, add report_mode=11 to print line shifts in pixels and print 3 decimal places in report_mode= 3, 6, 9, and 11. In emsao, xcsao, and sumspec, read PIXSHIFT from header and use it when rebinning for calibration adjustments and compute needed wavelength vectors Add pixshift argument to rebin() and rebinl() in rebin.x to adjust calibration. In wlcon.x, add wcs_pixshift() and wcs_getshift() and pixel shift in pixel to and from wavelength conversions.

2.4.2 March 25, 2005 Add constant graph scaling to sumspec.

2.4.1 March 16, 2005
Fix bug in bcvcorr so decimal RA's are correctly converted to hours. In compbcv.c, fix bug so decimal RA's are correctly converted to hours.

This is an *important* fix for anyone who cares about radial velocity accuracy to better than 100 km/sec and has RA and DEC in decimal degrees in their spectrum headers as the magnitude of the fix can be over 40 km/sec.

2.4.0 February 23, 2005
In eqwidth, debug and add net flux and various possible ways to scale it. Fix bug in bcvcorr so keyword values for position and date can be used.

2.3.9 October 19, 2004
Fix equivalent width computation in emsao so units match.

2.3.8 September 28, 2004
Add 3 parameters to eqwidth--atrest, bypix, byexp--to output sky fluxes at assumed rest wavelengths, normalized by exposure time and the number of rows from which the signal was summed to be subtracted from an extended object. (but program is still not tested)

2.3.7 August 25, 2004
Use cont_remove in sumspec instead of contout to remove continuum from input spectra, fixing a bug. Fix lots of type mismatches using gcc-based compilers on Redhat Linux version.

2.3.6 July 20, 2004
If velocity is changed using 's' in xcsao, emsao, and qplot, update the spectrum header.

2.3.5 June 16, 2004
In xcsao, a "+" at the start of the emission line filename always labels emission lines. In sumspec, options were added to return the fit to continuum rather than removing it and to use a list of output files.

2.3.4 January 16, 2004
Print nonspectral dispersion message only in debug mode in getimage()

2.3.3 August 1, 2003
Add the ability to read first extension of multi-extension FITS file. Eventually there will be new parameters, specext and tempext to read ranges or lists of file extensions, but not yet.

2.3.2 June 2, 2003
Add smoothing of output spectrum to sumspec. Clean up bcvcorr so it actually handles all of its input options correctly.

2.3.1 December 2, 2002
Fix bug in emsao renormalization check and boost renormalized spectra so all pixels are positive in. Add min, max pixel in xcsao if debug.

2.3.0 October 8, 2002
Add eqwidth task, based on IRAF noao.onedspec.sbands, to do photometry on redshifted data at wavelengths specified in the rest frame.

2.2.9 September 17, 2002
Allocate large vectors only once

2.2.8 August 17, 2002
Add report mode 16 to XCSAO for per template wavelengths

2.2.7 May 29, 2002
Add per spectrum velocity shifts to sumspec.

2.2.6 March 29, 2002
Add per spectrum wavelength (or pixel) limits to sumspec. Accept UTSTART as well as UTOPEN for observation beginning time

2.2.5 February 5, 2002
Ignore pixels with values less than MIN_PIXEL_VALUE at ends of spectra Replace pixels with values less than MIN_PIXEL_VALUE elsewhere in spectra In compbcv.x, allow use of new keywords OBS-LONG, OBS-LAT, and OBS-ELEV

2.2.4 September 19, 2001
Add 10th result reporting mode to emsao with line info only. Drop SPECDIR from file name in headings. Fix units check in getimage().

2.2.3 July 31, 2001
Change cross-correlation velocity information in header when template changed interactively in emsao and xcsao using the 't' cursor command. Fix pixel cross-correlation so it works. Add option to ignore zeroed pixels in continuum fit and removal. Add option in sumspec to remove continuum after rebinning (contout). Add option in sumspec to write each input file to a separate output file (composite file name is ""). Separate linespec and sumspec source directories from Makespec into Linespec and Sumspec, with shared tasks into Util.

2.2.2 April 3, 2001
Fix emsao and plotspec.x in several places to deal with right-to-left spectra. Plot text info after spectrum in emsao so it all displays on xgterm. Match arguments in sumspec so renormalization works.

2.2.1 February 9, 2001
Fix bug in emsao so emission line structures are always initialized correctly. Fix bug in xcsao to deal with right-to-left dispersion. Print aperture separately in xcsao mode 12 report and emsao one-line reports.

2.2.0 September 13, 2000
Add options to xcsao to cross-correlate in wavelength and pixel space by changing the "correlate" parameter into a string. Allow pixel or wavelength limits to be specified for templates in xcsao so several pieces of a single template spectrum, such as emission lines, may be correlated against an object spectrum. Add two new reporting modes to emsao , 8 to print wavelength information about fit emission lines on one line and 9 to print only wavelength shifts on one line.

2.1.27 August 10, 2000
Fix bug in emsao sorting of observed lines found by Erwin de Blok at ATNF.

2.1.26 August 2, 2000
Fix echelle mode spectrum number tracking. Print file name and aperture as title for object and template graphs

2.1.25 July 21, 2000
In sumspec, shift to first spectrum's barycentric velocity correction if svel_corr is not none.

2.1.24 July 6, 2000
In linespec and sumspec, specify wavelength dispersion by 3 of start and ending wavelength, wavelength/pixel, and number of pixels Automatically renormalize if maximum spectrum value is less than one. Clean up debugging code for renormalized cross-correlations.

2.1.23 June 8, 2000
Add equivalent width error to new report modes 0 and 7 in emsao.

2.1.22 April 28, 2000
Change years from 0-120, not just 0-99, to 1900+year. Some instrumentation write 100 instead of 00 for 2000 in the old FITS format.

2.1.21 March 6, 2000
Fix bug in linespec which caused wavelength to be multiplied 2+Z instead of 1+Z if redshift was entered as Z instead of velocity.

2.1.20 January 25, 2000
Read SUBCONT flag in spectrum header to find out whether to subtract continuum. If T, remove continuum; if F, do not. If it is not found, remove continuum.

2.1.19 December 8, 1999
Free spectrum WCS when freeing image stops runaway memory use when looping through large numbers of spectra in xcsao, emsao, or sumspec.

2.1.18 September 24, 1999
Fix qplot mode of xcsao to update best template information, including R when a different best template is selected.

2.1.17 September 15, 1999
Fix tab table output in xcsao (report_mode= -8, -10, -11, -12, or -14)

2.1.16 September 7, 1999
Write CD as well as CDELT in sumspec. Add gio.h dependencies in mkpkg.

2.1.15 August 24, 1999
Add vel_plot keyword to xcsao and velplot keyword to zplot, so combination velocity-redshifted lines can be displayed by default in dispmode > 0. When continuum is divided out in sumspec, the new continuum is 1. A new option for cont_remove, "divzero", divides by the continuum and subtracts 1 so the spectrum can be cross-correlated. This is what "divide" did in version 2.0 and all previous 2.1 betas, but it is not what you want if you plan to compute equivalent widths. Read templates from header if NTEMP is set as well as if CZPARAMS is set.

2.1.14 July 29, 1999
Add tab table output option to xcsao. In sumspec, copy entire header if single file in and out, even if there are multiple spectra from that file. In sumspec, normalize by dividing out the mean times an input constant. Add display with continuum subtracted to xcsao.

2.1.13 July 23, 1999
Add tab table output option to emsao. Replace blank fields with underscore.

2.1.12 July 16, 1999
Fix bug so qplot can update spectrum headers in both xcsao and emsao. If save_vel=yes and correlate or linefit =no the programs run in qplot mode, where nothing will be wriitten unless new fits or correlations are done.

2.1.11 June 30, 1999
Fix bug in xcsao which caused template heliocentric velocity correction and header velocity to be ignored. In debug mode, note which needed parameters are missing when the heliocentric velocity correction cannot be computed.

2.1.10 June 25, 1999
Add display modes 4 and 5 in emsao and xcsao to display spectrum with continuum subtracted. In emsao, add cursor commands to interactively modify some continuum fit parameters: C sets continuum fit parameters, S sets the VELOCITY keyword.

2.1.9 June 15, 1999
Add option in sumspec to zero or fill parts of spectra known to be bad. If they are zeroed, continuum is fit to an interpolated spectrum, and the bad pixels are zeroed after the continuum is removed. Fix fatal bug in linespec

2.1.8 May 21, 1999
Fix minor bug in filllist and change UT from end to start of observation in juldate.x, adding UTEND to UTMID and UTOPEN as possibilities for computing the Julian Date in conjunction with EXPOSURE or EXPTIME if the Julian Date is not already ain the header as GJDN or MJD-OBS. Try DATE keyword if DATE-OBS is not present

2.1.7 May 11, 1999
Fix bugs so that sumspec can stack rebinned spectra

2.1.5 March 30, 1999
Search IRAF database for observatory position using OBSERVAT header keyword if observatory position is not in the spectrum header, for computation of the geocentric part of the barycentric velocity correction.

2.1.4 March 19, 1999
Fix logic in sumspec so multiple spectra are summed correctly.

2.1.3 March 18, 1999
Multiply by 1000 when renormalizing so that continuum is not less than 1 so S/N for line search in emsao and continuum removal in xcsao and sumspec is a usable number.

2.1.2 March 12, 1999
Fix bug so that no error message is returned if an object spectrum file cannot be opened READ_WRITE if it can be opened READ_ONLY and no writing is to be done.

2.1.1 December 30, 1998
Log normalization factor in sumspec for first spectrum. Fix bug in xcsao to properly deal with template spectrum lists with pathnames.

2.0 31 July 1998
This release is what is described in our PASP paper, which was published in August 1998.
  • Three new tasks have been added:
    bcvcorr to deal with any observatory parameters which might throw off the inline computation of the barycentric velocity correction,
    sumspec to create a composite spectrum from multiple spectra taken at different times, and
    linespec to create an artificial spectrum from a list of emission and/or absorption lines.
  • The unsupported Fourier quotinent task fquot has been dropped.
  • xcsao's new parameters include
    fixbad and badlines specify regions of a spectrum to remove before processing. A line list is provided to remove the regions around night sky emission lines.
    specband and tempband better specify which spectra to read from multispec files.
  • emsao's new parameters include
    specband and skyband to better deal with multispec spectra,
    fixbad and badlines specify regions of a spectrum to remove before processing.
    mincont to determine whether area or equivalent width is computed,
    lwmin and lwmax for the minimum and maximum variation from the mean line width to be accepted, and
    lsmin for the minimum ratio of the equivalent width (or area) to its error for a line to be accepted.
  • Because of all of these new parameters, users should run RELEARN on any tasks they have used in the past.
  • Other changes to tasks include:
    Implementing FITS/ISO standard dates so program is Y2K compliant,
    fixing precision problems in the barycentric velocity correction,
    fixing the option to divide by the continuum in xcsao instead of subtracting it, which is set by a template flag, DIVCONT,
    adding the ability to switch between templates in the final displays of xcsao and emsao, and
    fixing a variety of other bugs.

    1.9 December 5, 1995
    Bugs fixed, but not a major release.

    1.8 September 28, 1995
    The major change is the ability to use either emsao and xcsao to display previous results saved in the image header. xcsao has two final displays, the old one with both spectrum and correlation peak and complete per- template correlation data, and the emsao display with emission and absorption lines labelled. A quality flag can be set in the header from either final display in either xcsao or emsao. If no correlation is done (correlation=no), only the final velocity information is rewritten by xcsao. If no new line fit is done (linefit=no), emsao writes out only the final velocity information, not overwriting the per-line results. A new task, qplot, was added to check redshift results after batch runs. There were also many minor bug fixes.

    1.7 June 1, 1995
    Add continuum removal, explicit emission and rejection limits, and zero-padding as optional template header-parameter-directed operations. The boolean zero_pad parameter was changed to the character zeropad to allow zero-padding to be optionally controlled by the template spectrum header parameter ZEROPAD. czinit, which was a yes or no boolean in previous versions of RVSAO has turned into the character string vel_init in RVSAO 1.7 to allow an initial velocity to be set from the czguess parameter or from a previously-obtained correlation, emission, or combined velocity in the header. Parameters s_abs_reject, s_em_reject, t_abs_reject, and t_em_reject have been moved to xcsao from CONTPARS as they are used to prepare spectra only for cross-correlation.

    1.6 February 27, 1995
    Optionally display the same summary in xcsao as emsao and allow template-directed high-pass filtering in xcsao so that narrow line templates, such as those containing emission lines can be used. To enable this option, square-root cosine-bell filtering is now done to the object and template spectrum transforms rather than cosine-bell filtering the correlation.

    1.5 September 9, 1994
    This version writes more complete results from emsao and xcsao to the image header. emsao gets larger emission line names and a parameter to specify the dispersion error, as well as a new summary page. xcsao adds parameters to allow emission line chopping in xcsao to be controlled by image header parameters, allowing emission line templates to be used, and adds optional zero-padding of transforms before cross-correlation to improve errors.

    1.4 June 23, 1994
    Fixing many small bugs, this version was never released ouside of SAO.

    1.3 March 23, 1994
    Improve handling of missing or unwriteable files, add a cursor option to set peak search width in xcsao, and improve cursor line selection in emsao. Add and improve cursor commands in emsao and add spectrum editing in xcsao. Greatly improve handling of multispec files as both object and template spectra. Add ZVEL CL script to run both xcsao and emsao on a file or list of files.

    1.2 December 3, 1993
    Handling of multispec spectra is improved. Multispec spectrum numbers are used whenever a spectrum is specified in text or graphical output.

    1.1 August 24, 1993
    IRAF MWCS spectrum files can now be read as well as older formats.

    The lesser-used xcsao reporting modes were cleaned up. This is the last version of RVSAO which can run on pre-MWCS/multispec IRAF (2.08) systems.

    1.01 February 10, 1993
    An improved help file for emsao was added, including some hints on using cursor mode and fixes some bugs in cursor line identification. The heliocentric velocity correction is now correctly applied. (Barycentric corrections from the image file header value have always worked.)

    1.00 February 2, 1993
    A number of small bugs in xcsao and emsao were fixed, and FQUOT got further before crashing (sometimes not even crashing). A parameter was added to the emsao emission line table to allow the width of the spectrum to be fit for each line.

    0.99 August 12, 1992
    Multispec handling was cleaned up, and some bugs in the cursor interaction section of emsao were fixed, especially with regards to line ID. A variety of bugs were fixed in the way velocity results are saved and combined velocities computed for SAOTDC archive files and IRAF image headers. Many small fixes were made, especially in emsao.

    0.98 April 24, 1992
    Multispec capabilitieswere improved by adding three new parameters to xcsao:
    specnum, a list of spectra in a multispec file to be correlated,
    tempnum, a list of spectra in a multispec file to be used as templates
    echelle, which is set to "yes" if the spectrum and template are both multispec echelle files--the same list, specnum, is used.
    The maxshift and minshift parameters are now in km/sec, instead of pixels in Fourier space, which should make appropriate values more obvious. The following parameters have been added to emsao:
    specnum, a list of spectra to process from a multispec file,
    tempnum, a list of corresponding sky spectra in the multispec file,
    emlines, a file containing a list of emission lines,
    emcombine, a file containing a list of combined emission lines,
    npfit, the number of pixels to fit around each line peak,
    npcont, the number of pixels to fit around each line continuum,
    wspan, the wavelength to search around each redshifted line center,
    ablines, a file containing a list of absorption lines to label,
    emsearch, a file containing a list of the strongest emission lines.
    Local modifications of the line lists is now possilble without changing the program, and changes to the parameters of the line fits allow use of emsao on a wide range of types of spectra.

    Multispec reading capability was added.

    Version 0.96 adds correct parameters for FQUOT and fixes a bug in pkwidth which would cause xcsao to bomb if a number of points rather than a peak fraction to fit was specified.

    Emission lines are properly removed if IRAF continuum fitting is chosen and several argument mismatches are corrected in subroutine calls. emsao no longer gives emission line centers that are one pixel off.

  • Last updated August 13, 2008