Makee: Wavelength Scale Formats (as of 2008)

The 2D spectra (output by makee) have a wavelength scale for each echelle order specified by a 6th order polynomial of the form:     wavelength in Angstroms = coef(0) + coef(1)*pixel + coef(2)*pixel*pixel + ... , where pixel is the column number.

For each order, two FITS header cards are added. The two card names have the format: WV_0_## and WV_4_## where "##" is the echelle order number on a scale where the bluest order of a given exposure is number 01. Each card contains four values:

WV_0_## = ' coef(0) coef(1) coef(2) coef(3) '
WV_4_## = ' coef(4) coef(5) coef(6) coef(7) '

where coef(7) will always be set to 0. Example:

WV_0_05 = ' 3.798860003E+03 +2.866401731E-02 -7.524915946E-07 -8.422777264E-11'
WV_4_05 = ' 8.209366207E-14 -5.373050237E-17 +1.107868830E-20 +0.000000000E+00'

for echelle order number 5 (also row number 5 in the output spectrum.)

See IRAF Compatibility for information on making the wavelength scale readable by IRAF.
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