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dkirkby / bossdata

Tools for accessing SDSS BOSS data
MIT License
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What is a TraceSet? #93

Closed dcunning11235 closed 9 years ago

dcunning11235 commented 9 years ago

This is a curve fit to...flux? Or not a fit at all, something else?

dkirkby commented 9 years ago

A traceset gives the parameters of a curve fit to each fiber's trace on the CCD, i.e., pixel offset as a function of wavelength. The fits are based on "flat" calibration exposures, which uniformly illuminate each trace, and "arc" exposures, which illuminate specific well-known frequencies.