Empirical fit to precision inclusive electron-proton cross sections in the resonance region

An empirical fit is described to measurements of inclusive inelastic electron-proton cross sections in the kinematic range of four-momentum transfer 0Q²<8 GeV² and final-state invariant mass $1.1<W<3.1$ GeV. The fit is constrained by the recent high-precision longitudinal and transverse separated cross section measurements from Jefferson Lab Hall C, unseparated Hall C measurements up to Q² ≈7.5 GeV², and photoproduction data at Q²=0. Compared to previous fits, the present fit covers a wider kinematic range, fits both transverse and longitudinal cross sections, and features smooth transitions to the photoproduction data at Q²=0 and deep inelastic scattering data at high Q² and W.