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MODIFY BEAM_EFF

        LAS\MODIFY BEAM_EFF Value
        LAS\MODIFY BEAM_EFF /RUZE [B0 Sigma]

    Change the beam efficiency.

    The first syntax allows to define the new beam efficiency from a  single
    value  for  the  whole spectrum. If the beam efficiency previously had a
    non zero value, the spectrum intensities and affected header  parameters
    are  rescaled  according  to the old and new values. Otherwise, only the
    beam efficiency is set to the new value.

    The second syntax allows to use the Ruze's equation, which is more suit-
    able for large band spectra:
        Beeff(lambda) = B0*exp(-(4*pi*Sigma/lambda)**2)
    B0  is the scaling factor with no units (between 0 and 1), and Sigma the
    width factor in microns. If the beam efficiency previously had a non ze-
    ro  value, a rescale factor is evaluated for each channel and is applied
    to the intensities, the new beam efficiency is set to  the  one  at  the
    center  of the spectrum, and the affected header parameters are rescaled
    according to this new value. Otherwise, only the beam efficiency is  set
    to this new value.
    B0 and Sigma can be omitted for 30M observations after 01-APR-2009. Val-
    ues measured at the 30M will be displayed and used in this case.


Gildas manager 2018-10-16