
Change to the GSPC CCFThe GSPC CCF has been modified to include new effective areas (A_{E}) as given in EXOSAT Express No. 6. These serve as a basis for deriving new absorption efficiencies (E_{A}). The relation between A_{E} and E_{A} for energy E is
with A_{G} = effective geometric area A_{X} = Xray acceptancySince the energies E_{i}, i = 150 with defined effective areas A_{E}(E_{i}) as given in the Express differ from the energies E_{J}, J= 150 as given in data type 3 (AE) of the GS calibration data, corresponding areas A_{E}(E_{J}) were calculated from A_{E}(E_{i}) via linear interpolation. Using the existing calibration values for A_{G} (data type 1 (DC)) and A_{X} (data type 3 (AE)), i.e.:
A_{G} = 150 cm^{2}equ.(1) finally gives 50 pairs of E_{J}/E_{A}(E_{J}) To avoid a change in the layout of the data type 3 (AE), all values E_{A}(E_{J}) are given with an accuracy of 3 digits so that there can be small discrepancies between the original effective areas and the areas derived from equ.(1). these discrepancies are of the order of a few x 0.1% and can therefore be ignored. M. Gottwald
