aTmcam: a simple atmospheric transmission monitoring camera for sub 1% photometric precision | Conference Paper individual record
abstract

Traditional color and airmass corrections can typically achieve ∼0.02 mag precision in photometric observing conditions. A major limiting factor is the variability in atmospheric throughput, which changes on timescales of less than a night. We present preliminary results for a system to monitor the throughput of the atmosphere, which should enable photometric precision when coupled to more traditional techniques of less than 1% in photometric conditions. The system, aTmCam, consists of a set of imagers each with a narrow-band filter that monitors the brightness of suitable standard stars. Each narrowband filter is selected to monitor a different wavelength region of the atmospheric transmission, including regions dominated by the precipitable water, aerosol optical depth, etc. We have built a prototype system to test the notion that an atmospheric model derived from a few color indices measurements can be an accurate representation of the true atmospheric transmission. We have measured the atmospheric transmission with both narrowband photometric measurements and spectroscopic measurements; we show that the narrowband imaging approach can predict the changes in the throughput of the atmosphere to better than ~10% across a broad wavelength range, so as to achieve photometric precision less than 0.01 mag. © 2012 SPIE.

authors
author list (cited authors)
Li, T., DePoy, D. L., Kessler, R., Burke, D. L., Marshall, J. L., Wise, J., ... Allen, R.
publication date
2012
publisher
spie Publisher
keywords
  • Photometric PrecisionAtmosphereTransmissionExtinctionDark Energy Survey (des)Dark EnergyCtioPrecipitable Water