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Title: Precision Spectrophotometric Calibration System for Dark Energy Instruments

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.
Publication Date:
OSTI Identifier:
Report Number(s):
DOE Contract Number:
Resource Type:
Technical Report
Research Org:
Regents of the University of Michigan
Sponsoring Org:
USDOE Office of Science (SC)
Contributing Orgs:
University of Michigan
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS Dark Energy; Spectrograph; Calibration