High-cadence visible and infrared spectra of the Sun during eclipse

Four spectrometers were deployed at Camp Wyoba (altitude 2402 m) on Casper Mountain, WY. Three low-resolution (R less than or similar to 1000) Avantes spectrometers obtained useful spectra from 310 nm to 2.3 mu m, at cadences from 8 to 500 ms.

To maximize photometric precision, these instruments were fed with optical fibers placed in the pupil planes of two small (D = 5 cm) telescopes, thereby integrating all light from the field of view. We also acquired higher-resolution (R approximate to 30000) spectra with a new infrared Fourier Transform Spectrometer, fed by a Sun-tracking heliostat, at a 2.5 s cadence. We calibrate the fluxes using counts obtained during partial eclipse, with known limb-darkened photospheric intensities.