relative fluxes

Rob Seaman seaman at noao.edu
Tue Jun 16 15:01:33 PDT 2009


On Jun 16, 2009, at 2:47 PM, Arnold Rots wrote:

> RELATIVE and NORMALIZED fluxes are dimensionless quantities: they are
> an ABSOLUTE flux divided by some reference flux value. Therefore the
> unit should be and empty string.

Question:  Would it make sense to reserve a token "UNITLESS" to make  
such cases explicit?

> An UNCALIBRATED flux could be expressed in some form of instrumental
> units, e.g., count/s.

Isn't the problem as described that the data are calibrated, but the  
calibration differs by a multiplicative scaling factor from some  
standard unit?  Presumably there may be cases with additive offsets as  
well: Celsius vs Kelvin spring to mind as an example.  (We should  
hesitate before going beyond linear :-)

Tack BSCALE and BZERO onto every value?

Rob



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