The analysis of the momentum difference between charged hadrons in high-energy proton-proton collisions is performed in order to study coherent particle production. The observed correlation pattern agrees with a model of a helical QCD string fragmenting into a chain of ground-state hadrons. A threshold momentum difference in the production of adjacent pairs of charged hadrons is observed, in agreement with model predictions. The presence of low-mass hadron chains also explains the emergence of charge-combination-dependent two-particle correlations commonly attributed to Bose-Einstein interference. The data sample consists of 190 inverse microbarns of minimum bias events collected with proton-proton collisions at a center-of-mass energy of 7 TeV in the early low-luminosity data taking with the ATLAS detector at the LHC.
The inclusive Delta as a function of $Q$, in the interval 0.02 GeV < Q < 2 GeV.
The Delta(3h), for 3-hadron chains with mass below 0.59 GeV, as a function of $Q$, in the interval 0.02 GeV < Q < 0.36 GeV.
The Dalitz plot, for 3-hadron chains with mass below 0.59 GeV. Coordinates X = sqrt(3)(T0-T2)/sum(T) , Y = 3T1/sum(T) - 1. T0/T1/T2 stand for kinetic energy of hadrons in the rest frame of the triplet ( hadrons 0 and 2 form like-sign pair).
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