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The extraction of the orders and the calculation of the coefficients of
interpolation for the wavelength calibration are performed, just after the exposure, by
the ELODIE reduction software. These coefficients are used in formula (1) to establish the
relation between pixels and wavelengths.
| |
(1) |
where is the order of the spectrum,
the number of the pixel in a
given order, Ti and Tj the
values of the Chebyshev polynomial of order i and j at the points and and A(i,j) the
coefficients of the interpolation.
In equation (1), and are x and 1/k normalized
on the [-1,1] interval by a linear transformation.
9/11/1998