Extracting the hadronization timescale in s~(1/2) = 7 TeV proton-proton collisions from pion and kaon femtoscopy

摘要

A hadronic rescattering model with the proper hadronization time width as the free parameter is compared with charged pion and charged and neutral kaon femtoscopy measurements from the LHC ALICE experiment for s~(1/2) = 7 TeV proton-proton collisions. Comparisons between the model and measurements aremade for one-dimensional source parameters in several charged multiplicity and transverse particle pair momentum bins. It is found that a reasonable description of the measured source parameters by the model is obtained for a hadronization proper time width of 0.4 ± 0.1 fm/c, which is in agreement with an estimate based on the uncertainty principle. The model calculations also suggest that (1) some form of collectivity is necessary to describe the multiplicity dependence of the measured radius parameters, and (2) the underlying physical size and timescale of the collision is significantly larger than what the extracted radius parameters and hadronization proper time width would imply.