Nukleárny seminár - Róbert Astaloš (4.5.2016)
v stredu 4.5.2016 o 14:00 hod. v miestnosti F1/364
Od: Jaroslav Staníček
Nukleárny seminár Katedry jadrovej fyziky a biofyziky FMFI UK, Slovenskej fyzikálnej spoločnosti a Slovenskej nukleárnej spoločnosti
Prednášajúci: Mgr. Róbert Astaloš, PhD.
Názov: Correlation measurements by the ATLAS experiment
Termín: 4.5.2016, 14:00 hod., zasadačka KJFB (F1/364)
Three correlation measurements analyses by the ATLAS detector are presented. Bose-Einstein correlations (BEC) measurement serves as a probe of space-time geometry of the hadronization region and leads us to a better understanding of quark confinement effects. BEC are observed as an enhancement of small four-momentum differences Q in like-sign charge track pairs, compared to the unlike-sign charge pairs. The difference between like-sign and unlike-sign Q distributions is also reproduced by selection of low mass hadron chains with properties as predicted by the quantized (helix-like shaped) string fragmentation model. The contribution of small transverse momentum tracks to the correlations is discussed.
Long-range pseudorapidity correlations (ridge effect) was studied in the proton-proton collisions. New 13 TeV Ridge results including additional statistics let measurements to higher multiplicity (150 reconstructed tracks). No multiplicity or energy (compared to 5 TeV) dependence on the long-range correlations strength is seen.