摘要：Solar soft X-ray irradiance measured by the GOES X-Ray Sensor (XRS) is a critical measurement for space weather operations. At present, there is a primary GOES XRS operating with a second XRS in storage on orbit. This configuration results in gaps in critical observational coverage when the primary XRS is nonoperational such as during satellite maneuvers and during the spring and fall eclipse seasons. EUV Variability Experiment (EVE) on NASA's Solar Dynamics Observatory provides near–real-time measurements of the solar soft X-ray irradiances at wavelengths similar to XRS. This study examines the accuracy in using EVE data as a proxy for GOES XRS. Using EVE data, we develop three different solar irradiance index models, which are then tested to determine how well they predict the XRS irradiances and magnitude (GOES class) of solar flares. The best performing index model has been implemented in Version 3 of EVE data and is publicly available within minimal latency through the EVE Science Processing and Operations Center.
