Measurement of inclusive epep cross sections at high QQ2 at s√s√=225 and 252 GeV and of the longitudinal proton structure function FFLL at HERA

Inclusive ep double differential cross sections for neutral current deep inelastic scattering are measured with the H1 detector at HERA. The data were taken with a lepton beam energy of 27.6 GeV and two proton beam energies of Ep=460 and 575 GeV corresponding to centre-of-mass energies of 225 and 252 GeV, respectively. The measurements cover the region of 6.5×10−4≤x≤0.65 for 35≤Q2≤800 GeV 2 up to y=0.85 . The measurements are used together with previously published H1 data at Ep=920 GeV and lower Q2 data at Ep=460 , 575 and 920 GeV to extract the longitudinal proton structure function FL in the region 1.5≤Q2≤800 GeV 2 .