mag

 MAG N1 N2 COMP FILT OUT -- Computes the relative magnitude of a list of
                        stars compared to a template star by integration
                        over a bandpass provided by the user.

 Parameters:
            N1   -- First object spectrum
            N2   -- Last object spectrum
            COMP -- Star to compare with
            FILT -- Table of data with columns of wavelength and response.
                    The wavelengths (angstroms) should monotonically
                    increase but do not have to be uniform. Response (QE)
                    should go to zero at ends. 
            OUT  --  for terminal only
                    name -- for a file name
                    !name to store in real header with name = name

 Details: the magnitude is photon weighted. i.e. it is assumed that you
 would measure it with a detector that reponds to the number of incdent
 photons. This ends up as an integral over filt*fnu*dlambda/lambda.

 The table will be linearly interpolated between values, but it is taken to be
 constant outside the range of the wavelength. Therefore the response should 
 go to zero at either end if you want a finite bandwidth. The integration will 
 not extend beyond the ends of the spectrum. Masked regions are ignored, i.e.
 they are effectively set to zero.

 The output is the magnitude of the target spectra - magnitude of COMP

This command belongs to the class: measurement


Tom Marsh, Warwick