GREAT/SOFIA atmospheric calibration

TL;DR

This paper discusses the calibration process for GREAT/SOFIA atmospheric observations, focusing on frequency-selective calibration and the challenges of matching atmospheric models with observed emission at high spectral resolution.

Contribution

It introduces a calibration strategy for GREAT/SOFIA data that accounts for narrow and broad atmospheric spectral features and addresses model-data discrepancies.

Findings

Calibration strategy improves atmospheric transmission accuracy

Identifies issues in atmospheric model predictions

Enhances data quality for high-resolution spectral observations

Abstract

The GREAT observations need frequency-selective calibration across the passband for the residual atmospheric opacity at flight altitude. At these altitudes the atmospheric opacity has both narrow and broad spectral features. To determine the atmospheric transmission at high spectral resolution, GREAT compares the observed atmospheric emission with atmospheric model predictions, and therefore depends on the validity of the atmospheric models. We discusse the problems identified in this comparison with respect to the observed data and the models, and describe the strategy used to calibrate the science data from GREAT/SOFIA during the first observing periods.