Coronal abundances obtained from serts and Yohkoh-SXT data

Coronal abundances for active region AR 7563 were obtained using a combination of broad-band filter data from Yohkoh SXT and simultaneous spectral line data from the SERTS rocket taken during its flight on 1993 August 17. We have used a forward-folding technique to determine the emission measure distribution of the active region plasma using only the SERTS iron lines and the SXT filters (which are sensitive primarily to iron and used mainly to constrain the high-temperature end of the emission measure distribution). We then adjusted the abundances of the other elements to achieve the best agreement with this curve. Magnesium, aluminum, silicon, sulfur, and nickel were changed to 110%, 88%, 80%, 80%, and 115%, respectively from standard published values.