[Ifeffit] Bkg fit in Artemis

Hi All, I like to understand the way how the background fitting is done in Artemis. How the background functions are obtained (or defined)? How do we use the bkg fit in analyzing the data? I have a good idea about how Athena does the bkg reduction. But have no clue in case of Artemis. I would appreciate if somebody can direct me to an article written on this or can give a brief introduction about it. Thanks. Aranwela