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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 2018-05-27