  Charged-particle spectra obtained in 0.15 nb${}^{-1}$ of Pb+Pb interactions
at $\sqrt{{s}_\mathsf{{NN}}}=2.76$TeV and 4.2 pb${}^{-1}$ of pp interactions at
$\sqrt{s}=2.76$ TeV with the ATLAS detector at the LHC are presented in a wide
transverse momentum ($0.5 < p_{\mathrm{T}} < 150$ GeV) and pseudorapidity
($|\eta|<2$) range. For Pb+Pb collisions, the spectra are presented as a
function of collision centrality, which is determined by the response of the
forward calorimeter located on both sides of the interaction point. The nuclear
modification factors $R_{\mathrm{AA}}$ and $R_{\mathrm{CP}}$ are presented in
detail as function of centrality, $p_{\mathrm{T}}$ and $\eta$. They show a
distinct $p_{\mathrm{T}}$-dependence with a pronounced minimum at about 7 GeV.
Above 60 GeV, $R_{\mathrm{AA}}$ is consistent with a plateau at a
centrality-dependent value, within the uncertainties. The value is
$0.55\pm0.01(stat.)\pm0.04(syst.)$ in the most central collisions. The
$R_{\mathrm{AA}}$ distribution is consistent with flat $|\eta|$ dependence over
the whole transverse momentum range in all centrality classes.
