New methods to measure integrated luminosity at BES

Two new methods are introduced for the first time at BES to measure the integrated luminosity from events in large angle produced by QED dimuon and two gamma production processes. With these methods,the integrated luminosities of the 6 energy points at 2.6,3.2,3.4,3.55,4.6 and 5.0 GeV scanned for the measurement of R are determined. The measured integrated luminosities are consistent with that determined using large angle Bhabha events.