Measurement of neutral current e±p cross sections at high Bjorken x with the ZEUS detector

The latest results of the ZEUS collaboration on the high Q2, the exchanged boson virtuality, high Bjorken x region up to values of x = 1 are presented. Differential cross sections in x and Q2 are given for Q2 > 725 GeV2. An improved reconstruction method and a substantially increased amount of data allow a finer binning in the high-x region of the neutral current cross section and lead to a measurement with much improved precision compared to a similar earlier analysis. The measurements are compared to Standard Model expectations based on a variety of recent parton distribution functions.