| 1.
| Read parameters
| Including from "makee.HIRES.param" file.
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| 2.
| Read OBJECT file FITS header
| To get parameters and information.
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| 3.
| Read other files FITS headers
| Including the BIAS, FLAT, STAR, and ARC.
To get more information.
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| 4.
| Read and/or create the BIAS 1D image
| A processed copy is written out for later use.
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| 5.
| Read and process FLAT image
| A processed copy is written out for later use to save memory.
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| 6.
| Rough detemination of the slit length using FLAT image
| Using a cross correlation technique.
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| 7.
| Read and process STAR image
| Includes baseline correction and windowing of image.
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| 8.
| Fit order traces using STAR image
| Start by finding peaks and then centroid and "follow" the trace in each direction.
Produces output plot (e.g. trace-204.ps ).
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| 9.
| Find background limits for each order using FLAT image
| Look for ends of the slit by summing along the trace fit.
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| 10.
| Read OBJECT image
| Load into memory.
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| 11.
| FLAT field correction
| Rescale entire FLAT image by a single constant and divide OBJECT image by FLAT image
|
| 12.
| Find object profile and boundaries
| Use a precentage of total object flux to set limits.
Produces output plot (e.g. profiles_205.ps ).
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| 13.
| Extract spectra
| Use dispersion-direction profile fits to do optimal weighting extraction.
Cosmic rays are masked in the object and background regions.
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| 14.
| Extract FLAT spectrum (go back to step 10.)
| Produces output file for user reference.
|
| 15.
| Extract ARC spectrum (go back to step 10.)
| Produces output file for user reference.
|
| 16.
| Wavelength calibration
| Use a database of previously calibrate
arclamp spectrum to guess the positions of
Thorium emission lines. Fit polynomials to
each order using information from adjacent orders.
Example of residuals plot: Arc-206-fr.ps .
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| 17.
| Apply nighsky emission line correction
| Shift the wavelength scale (all orders) (in pixels) based on
known and identified nightsky emission lines.
Example of residuals plot: Arc-206-sky.ps .
|
| 18.
| Copy wavelength scale to the object
| The coeffecients of the 6th order polynomial are stored
in the FITS header. Vacuum and heliocentric corrections
are applied.
|
| 19.
| Write out spectra
| Produce Flux-*.fits and Err-*.fits spectrum output files.
These are 2-D images where each row is a separate order.
Spectrum example: Flux-205.ps .
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| 20.
| Create other special spectra
| This includes DN-*.fits and s2n-*.fits.
|