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General Processing Utilities

• Rect The rectification of the spectrum by dividing of continuum fit spline. The fit is obtained as rubber band spline just by interactive setting of its control points. See Fig. 4. The result is a *.RUI file (Fig. 5).
• Filt The Fast Fourier filtering of the rectified spectrum. The power spectrum is shown with the possibility of setting the filter width by moving the edge-cutting line (see Fig. 6). The correction for microphotometer slit and emulsion profile is asked as well. The result is *.RFI file.
• Vel This module is a complete astrophysical toolbox for the determination of radial velocities, equivalent widths and higher order moments (e.g. skewness) of investigated spectral lines.
  • Radial vel Radial velocity measurement.
    • Measure lines Radial velocity of interesting stellar lines described in *.STL list is measured interactively in oscilloscopic or automatic mode. The x-position and measured wavelength are written in *.RV file. Then the heliocentric correction in the time of observation is inquired. This correction is used for the estimate of the line radial velocities, that are written into measurement protocol (either on printer or *.RVR file).
    • Recal RV's Just the new heliocentric correction is added to the already existing *.RV file and the *.RVR file is produced.
  • eq. Widths The equivalent widths of the stellar lines in the *.STL list are estimated. The spectrum has to be already rectified (with the continuum spline set). The enlarged line profile is shown and the user is asked to mark the central line intensity by moving the short tic along the profile. Then the FWHM line is drawn and the equivalent width calculated using the numerical integration. The results are written into *.EQW file (or to printer).
  • Moments The higher order moments of lines are calculated and written to *.MOM file. The moments are defined
    
    $$W_n=\int_{\phi} (\lambda - \lambda_c)^n [1-I(\lambda)] d\lambda ,$$
    
    
    where $\phi$ is the line profile, $\lambda_c$ the wavelength of the line center and $I(\lambda)$ the line intensity at given wavelength. The equivalent width is the zero order moment.
• Plot One or several spectra are prepared for the graphical output. A several questions are being asked about the plot dimensions, the continuum level (for each spectrum), the data file names, the plotted range, etc. These parameters are written into *.PLT file that may be used second time for the same plot (but with another data files).
  • On line plot The plot is made at the on-line connected HPGL compatible plotter. Up to eight color pens are driven.
  • Prep for laser printer The HPGL file *.PGL is produced, that may be sent to the plotter or converted to other graphic formats (e.g. PostScript) by means of HP2XX convertor.
• Synt This module is intended especially for the comparison of observed spectra with the synthetic ones, but other spectra may be processed as well. The processing includes the spectra comparison, addition and subtraction (producing differential spectrum).
  • RotateThe synthetic spectrum is described by a simple ASCII table of wavelength and corresponding flux in *.SYN file and the same for continuum flux in *.CNT file. The spectrum must be rotationally broadened with given rotation velocity before the next processing. The result is the (binary) *.RRI file.
  • Compare Two selected *.R?I files are shown on screen with the changeable radial velocity and weakening factor. On request the differential spectrum may be shown.
  • Subtract The same as above, but the differential spectrum is written into *.RDI file.
  • Add sp. The addition of two preselected spectra. The result is written into *.RAI file.
• File The toolbox of file conversion utilities.
  • change Dir Changes the working directory where all files are saved (e.g. to trial TEST directory).
  • Fits->spefo The conversion from 1D FITS file to SPEFO format.
  • Spefo->fits The export of SPEFO data to FITS file
  • Spefo->ascii The conversion from binary SPEFO format file to human-readable ASCII file that may be ASCII edited (e.g. to exterminate the cosmic spikes, detector errors).
  • Ascii->spefo The reverse transformation
  • View/edit The tool for viewing or editing of any rectified SPEFO file on screen display. Either individual points may be deleted, or the selected part of the spectrum may be replaced either by linear or spline fit. The resulting file has the *.RCI extension.