Related paper K$^0_{\rm S}$ and $\rm Λ$ production in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV Examples of invariant mass distributions for $\Kzs$ and $\rm\Lambda$. The filled areas to the sides of the peaks were used to fit the background in order to estimate the background level under the peaks, indicated as the light shaded areas. [png] [pdf]