The results of studies using the ATLAS detector at the CERN Large Hadron Collider of Bose-Einstein Correlations (BEC) in proton-proton collisions at a centre-of-mass energy of 13 TeV for pairs of like-charged particles each with |η| < 2.5, as measured for two kinematic ranges: the first with a minimum particle pT > 100 MeV and the second with a minimum particle pT > 500 MeV will be presented.
The integrated luminosities are approximately 151 μb-1 and 8.4 nb-1for the minimum-bias and high-multiplicity datasets, respectively. The BEC parameters, characterizing the source radius and particle correlation strength, are investigated as functions of charged-particles multiplicity (up to three hundred) and average pair transverse momentum (up to 1.5 GeV). The double-differential dependence on charged-particle multiplicity and average pair transverse momentum is also studied. A saturation effect in the charged particle multiplicity dependence of the BEC radius is confirmed for high charged particle multiplicity (above one hundred). Also, for double-differential intervals, a saturation effect is observed in the BEC radius for high charged particle multiplicities. The multiplicity and pair transverse momentum dependence of the BEC correlation strength and source radius parameters on the collision energy is also presented.