Precision Spectrophotometric Calibration System for Dark Energy Instruments

Schubnell, Michael S.

关键词: Dark Energy;    Spectrograph;    Calibration;   

DOI  :  10.2172/1187978
RP-ID  :  DOE-Michigan-SC7915
PID  :  OSTI ID: 1187978

学科分类：天文学(综合)

美国|英语

来源: SciTech Connect

【 摘 要 】

For this research we build a precision calibration system and carried out measurements to demonstrate the precision that can be achieved with a high precision spectrometric calibration system. It was shown that the system is capable of providing a complete spectrophotometric calibration at the sub-pixel level. The calibration system uses a fast, high precision monochromator that can quickly and efficiently scan over an instrument???s entire spectral range with a spectral line width of less than 0.01 nm corresponding to a fraction of a pixel on the CCD. The system was extensively evaluated in the laboratory. Our research showed that a complete spectrophotometric calibration standard for spectroscopic survey instruments such as DESI is possible. The monochromator precision and repeatability to a small fraction of the DESI spectrograph LSF was demonstrated with re-initialization on every scan and thermal drift compensation by locking to multiple external line sources. A projector system that mimics telescope aperture for point source at infinity was demonstrated.