Figure 7

Correlation strength $b_{corr}$ for separated $\eta$-$\varphi$ window pairs at $\sqrt{s}=0.9$ TeV as a function of $\eta$ separation, with fixed window width $\delta\eta$=0.2 and $\delta\varphi$=$\pi$/4 The panels are for different separation distances between the two azimuthal sectors:$\varphi_{\rm sep}=0$, $\pi/4$, $\pi/2$, $(3/4)\pi$ and $\pi$ MC results from PYTHIA6 Perugia 0 (blue lines), Perugia 2011 (orange dashed lines) and PHOJET(pink dashed lines) and string model (thin green lines) are also shown The bottom panelsshow the ratio $b_{corr}$ between data and MC results.