GIFTS System Calibration Requirements Flowdown

1
GIFTS System Calibration Requirements Flowdown

• Hank Revercomb
• 9 March 2004

2
GIFTS Overall Absolute Calibration Budget
Subject of BB CDR
3
GIFTS Top-level Absolute Calibration Budget
4
GIFTS Spectral Calibration Budget
Standard Atmosphereused for conversion
tobrightness temperature

3-sigma for single sample is 3 ppm-100 sample
average assumed
5
GIFTS Radiometric Calibration Budget (Absolute)
6
GIFTS Radiometric Calibration EquationBasis for
Uncertainty Modeling

• Radiance N derived from raw spectra of Earth
  (CE), Space (CS), and the internal Hot (CH) and
  Cold (CC) Blackbodies
• ?t is the signal transmission of the telescope
  mirrors ?m is the transmission of the Blackbody
  pick-off mirror
• Bi is the Radiance from the Hot, Cold, and Space
  References
• eg. BH?H B(TH) (1- ?H) B(Tstr), where B(T)
  is the Planck function and
• Tstr is the effective structure temperature for
  reflection

7
GIFTS Absolute Calibration-Longwave
Longwave Band (800 cm-1) Tc255, Th290, Ts240,
Tt280
Requirement
External BB
GIFTS
(excluding uncertainty in correction
forNon-linearity Polarization)
8
GIFTS Absolute Calibration-Shortwave
Shortwave Band (1800 cm-1) Tc255, Th290,
Ts240, Tt280
Requirement
External BB
GIFTS
(excluding uncertainty in correction
forNon-linearity Polarization)
9
GIFTS Calibration Error Sources-LW
Longwave Band (800 cm-1) Tc255, Th290, Ts240,
Tt280
0.3
0.3 K
NEN/40.05
10
GIFTS Calibration Error Sources-SW
Shortwave Band (1800 cm-1) Tc255, Th290,
Ts240, Tt280
0.5
0.3 K
NEN/40.0025
11
GIFTS Blackbody Budget
Subject of this BB Subsystem CDRBudget is 0.5 K
3-sigma Absolute 0.1 K 3-sigma
Reproducibility, by analogy