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SDO EVE ESP Radiometric Calibration and Results

Published

Author(s)

Leonid Didkovsky, D L. Judge, Seth Wieman, T N. Woods, Phillip Chamberlin, Andrew Jones, Francis Eparvier, Matthew Triplett, Donald Woodraska, D R. McMullin, Mitchell L. Furst, Robert E. Vest

Abstract

The Solar Dynamics Observatory (SDO) Extreme ultraviolet Solar Photometer (ESP), as a part of the Extreme ultraviolet Variability Experiment (EVE) suite of instruments, was calibrated at the National Institute of Standards and Technology (NIST) on the Synchrotron Ultraviolet Radiation Facility (SURF) Beam Line 2 inFebruary 2007. Precise ESP alignment to the SURF beam was achieved through successive scans in X, Y, Pitch and Yaw, using a comparison of the four channels of ESP's internal quad photodiode as a measure of alignment.The observed alignment between the ESP and the other instruments in the EVE package was found to be in a very good agreement with that measured at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado during ESP/EVE integration. The radiometric calibration of the ESP photometers in the spectral window of around 4.4 nm (central order), and the four first order channels centered at about 18.9, 25.4, 29.8, and 36.1 nm was performed with SURF synchrotron spectra. The position of the SURF beam on the ESP entrance aperture for each energy and current was determined based on modeled quad diode (QD) photometer responses, and real photodiode count-rate data. This determined beam position was later used to obtain exact energy-wavelength-fux profiles for each of the calibration energies and to calculate the quantum efficiency of the ESP channels. The results of this calibration (quantum efficiencies) are compared to the previous ESP NIST calibration results
Citation
SPIE Proceedings--The International Society for Optical Engineering
Volume
6689

Keywords

EVE/ESP, NIST/SURF, radiometric calibration, Solar Dynamics Observatory

Citation

Didkovsky, L. , Judge, D. , Wieman, S. , Woods, T. , Chamberlin, P. , Jones, A. , Eparvier, F. , Triplett, M. , Woodraska, D. , McMullin, D. , Furst, M. and Vest, R. (2007), SDO EVE ESP Radiometric Calibration and Results, SPIE Proceedings--The International Society for Optical Engineering, [online], https://doi.org/10.1117/12.732868, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=840270 (Accessed January 27, 2022)
Created September 12, 2007, Updated October 12, 2021