(a) $v_1$ and (b) $\langle p_{\rm x}\rangle/\langle\pt\rangle$ versus pseudorapidity in Pb-Pb collisions at $\sNN=2.76$ TeV.
(c) $v_1^{\rm odd}$ compared to the STAR data for Au-Au collisions at $\sNN=200$ (62.4) GeV downscaled by a factor 0.37 (0.12). The statistical (systematic) uncertainties are indicated by the error bars (shaded bands). Lines (to guide the eye) represent fits with a linear (constant) function for $v_1^{\rm odd}$ ($v_1^{\rm even}$).