The relation between BCS line broadening and
velocity can be computed with BCS_BROAD. Some example calling sequences are:
IDL> Td6 = bcs_broad(Chan,TDoppw=TDoppw) ; Return temperature in (MK)
IDL> Vel = bcs_broad(Chan,Td6=Td6,/vel) ; Return velocity (km/s)
IDL> TDoppw = bcs_broad(Chan,Td6=Td6,/Gauss) ; Return Doppler FWHM (Ang)
where 
is the equivalent Doppler Temperature (MK) and 
is the
BCS channel number. The parameter 
does not include the
contribution due to the crystal (Lorentz) broadening, but is included
by BCS_BROAD when it makes its calculations, based on the value of
. There are several additional options available and there is a
keyword to return the crystal rocking curve width. Most conversions
between BCS line width and velocity or between line width and
temperature can probably be accomplished using this routine.