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Basic Information on clstats


Task: clstats
Purpose: Calculate dispersions, masses, etc for each clump from clfind file
Categories: utility

   The mass is calculated in the following way;
   we define X such that,
 
   X * (sum T) * delv = column density of molecular hydrogen
                        in units of 10^20 cm-2
 
   which implies that to convert to a mass, multiply by
 
   10^20 * meanmol * m(H_2) * Area
 

Key: in
        file name of data cube
        (no default)
 

Key: dist
        the distance to the object in pc
        (no default)
 

Key: disterr
        multiplicative error in the distance
        eg disterr=2 means dist is uncertain by a factor of 2
        (default=1)
 

Key: x
        the X-factor to convert between column density of the
        species observed to the column density of molecular hydrogen
        --- see above. (Note that this includes any corrections for
        abundance, excitation temperature, CMBR, antenna efficiency,etc.)
        (In units of 10^20, default=2.4)
 

Key: xerr
        multiplicative error in X -- from uncertainties in
        abundances, excitation temperature, efficiency, etc.
        (default=1)
 

Key: meanmol
        the mean molecular weight of the gas
        (default=1.38, corresponding to n(He)/n(H)=0.1)
 

Key: jyperk
        the number of Jansky's per Kelvin for these observations
        (default=1)
 

Key: xy
        "rel" or "abs" for the clump positions - v is always absolute
        (default=relative)
 

Key: rms
        optional input to specify the rms error in temperature
        for each pixel in the map (used to calcuate errors in
        the masses). Otherwise 0.5*DeltaT, where DeltaT is the
        clfind contour interval.
 

Key: nmin
        each clump must contain at least nmin pixels to be
        written out to output file
        (default=4)

Generated by miriad@atnf.csiro.au on 21 Jun 2016