Femtoscopy of proton-proton collisions at the LHC with the ALICE experiment

We present the results on two-particle Bose-Einstein correlations measured in proton-proton collisions at center of mass energies of sqrt{s}=0.9 TeV, sqrt{s}=2.76 TeV and sqrt{s}=7 TeV registered by the ALICE experiment at the Large Hadron Collider. Detailed analysis reveals that the three dimensional experimental correlation functions do not have Gaussian shape in two dimensions. We found that they are better described by an exponential functional form in the outward and longitudinal directions, while the sideward remains a Gaussian. This is interpreted as a result of a significant contribution of strongly decaying resonances to the shape of the emission region.