Precise charm-quark mass from deep-inelastic scattering

We present a determination of the charm-quark mass in the MS¯ scheme using the data combination of charm production cross section measurements in deep-inelastic scattering at HERA. The framework of global analyses of the proton structure accounts for all correlations of the charm-quark mass with the other non-perturbative parameters, most importantly the gluon distribution function in the proton and the strong coupling constant αs(MZ). We obtain at next-to-leading order in QCD the value mc(mc)=1.15±0.04(exp)−0.00+0.04(scale)GeV and at approximate next-to-next-to-leading order mc(mc)=1.24±0.03(exp)−0.02+0.03(scale)−0.07+0.00(theory)GeV with an accuracy competitive with other methods.