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DEEP2 Throughput

Below is some IDL code to  demonstrate how DEEP2 throughput corrections are applied:

IDL> ss = read_spec() ; ss.soec is in units of e- counts/pix/hour
IDL> flux = ss.flux*deimos_correction(ss.lambda) ; flux is now in e- counts/pix/hour and corrected for spectral shape
IDL> flux = flux*planck constant * speed of light/ss.lambda ; flux is now in energy/pix/hour

Copy this code into deimos_correction.pro, apply to observed-frame wavelengths.
  ; -> Converts e- counts to e- counts. <-
  ;       The inverse of this function returns the throughput of DEIMOS
  ;       
  ;       Following factor accounts for (but deimos_correction does not account for):
  ;               Primary mirror size             pi*499cm^2
  ;               counts/hour -> counts/second    3600 sec/hour
  ;               Angstrom/Pixel                  0.33 angstrom/pix
  ;               Energy per e-                   2.00e-8 erg/ lambda(angstrom)
  ;               And slit corrections
  ;       
  ;       To convert to E, multiply by 5.3 (+-1.3) e-17 / lambda(angstrom)
  ;               erg/s/Ang/cm^2
  ;
  ;       W/out slit corrections, multiply by  2.16e-17 / lambda(angstrom)
  ;
  ; npk
  function deimos_correction, $   ;  Correction factor to DEIMOS e- counts 
          lambda ;   in Angstroms
          return, 1./(-77.9026+0.0395916*lambda-7.49911e-06*lambda^2+6.29692e-10*lambda^3-1.97967e-14*lambda^4)
  end

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