xcsao Example 1. Graphs

If all of the possible interactive flags are turned on, the following graphs result from the correlation of one object spectrum against two template spectra. The xcsao parameters in italics turn on the following graphs. Except in the Summary section, all plots on the left are from the process of correlating against the absorption template spectrum, and all plots on the right are from correlating against the emission template spectrum. All intermediate graphs, except for that displayed for interactive continuum fitting, are displayed in cursor mode and expect the same set of cursor commands, especially q to continue.

Object Spectrum

If obj_plot = yes, the object spectrum is plotted and available for editing and examining. [spectrum]

Template Spectra

If temp_plot = yes, the template spectra are plotted and available for editing and examination.
[absorption line template] [emission line template]

Continuum Removal

If contpars.c_interactive = yes, the user can interact with this display, adjusting the continuum fit.
[continuum] [continuum]
[removed lines] If contpars.c_interactive = yes, s_emchop = yes, and absorption lines deeper than s_abs_reject and/or emission lines higher than s_em_reject are replaced by the fit continuum, those lines are plotted. No lines should be removed when cross-correlating against an emission line template.
If contsub_plot = yes, the spectrum is plotted with the continuum removed.
[spectrum-continuum] [spectrum-continuum]

Apodization

If apodize_plot = yes, apodized versions of the object and template spectra are plotted.
[spectrum apodized] [spectrum apodized]

Unfiltered Fourier Transforms

If fft_plot = yes, the Fourier transforms of the spectra and templates are plotted before they are filtered.
[spectrum FFT] [spectrum FFT]
[absorption template FFT] [absorption template FFT]

Unfiltered Cross-Correlation

If uxcor_plot = yes, the unfiltered cross-correlation against each template is plotted.
[absorption template cross-correlation] [emission template cross-correlation]

Filtered Fourier Transforms

If fft_plot = yes, the filtered Fourier transforms of the object and
[spectrum filtered FFT] [spectrum filtered FFT]
template spectra are plotted.
[absorption template filtered FFT] [absorption template filtered FFT]

Filtered Spectra

If tfft_plot = yes, filtered object and
[spectrum filtered] [spectrum filtered]
template spectra which are computed by inverse-transforming the filtered Fourier tranforms are plotted.
[absorption template filtered] [emission template filtered]

Cross-Correlations

If xcor_plot = yes, filtered cross-correlations of the object spectrum against each template are plotted. While in cursor mode, a peak to be used to fit the redshift may be selected using the p command.
[absorption template filtered cross-correlation] [emission template filtered cross-correlation]

Summary of Results

If dispmode = 1, this display is plotted to device showing the spectrum, the best cross-correlation, and the redshift results for each template used. [absorption line template cross-correlation]
If curmode = yes, the summary display may be changed to show other than the best correlation by typing T and responding with the sequence number of the template you want to use from the summary display. You can also switch to display the spectrum with labelled emission and absorption lines by typing l. [emission line template cross-correlation]
If dispmode = 2, this display is plotted to device showing the spectrum, with absorption and/or emission lines labelled, and the redshift results for each template used, along with any previously obtained emission lines results from <../../emsao/">emsao. [absorption line template velocity labelled lines]
If curmode = yes, the summary display may be changed to show the line positions at redshifts resulting from other than the best correlation by typing T and responding with the sequence number of the template you want to use from the summary display. You can also switch to display the spectrum and its cross-correleation by typing x. [emission line template velocity labelled lines]

[xcsao] [xcsao examples] [xcsao example 1]