Naslov
Centrality dependence of pion freeze-out radii in Pb-Pb collisions at √sNN=2.76 TeV

Autori
Adam, J. ; ... ; Antičić, Tome ; ... ; Erhardt, Filip ; ... ; Gotovac, Sven ; ... ; Mudnić, Eugen ; ... ; Planinić, Mirko ; ... ; Poljak, Nikola ; ... ; Simatović, Goran ; ... ; Utrobičić, Antonija ; ... ; Vicković, Linda ; ... ; Zyzak, M.

Kolaboracija
ALICE Collaboration

Izvornik
Physical review. C (2469-9985) 93 (2016), 2; 024905, 18

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
centrality ; freeze-out ; pion ; Pb-Pb

Sažetak
We report on the measurement of freeze-out radii for pairs of identical-charge pions measured in Pb--Pb collisions at √sNN=2.76 TeV as a function of collision centrality and the average transverse momentum of the pair kT. Three- dimensional sizes of the system (femtoscopic radii), as well as direction-averaged one- dimensional radii are extracted. The radii decrease with kT, following a power-law behavior. This is qualitatively consistent with expectations from a collectively expanding system, produced in hydrodynamic calculations. The radii also scale linearly with ⟨ dNch/dη⟩1/3. This behaviour is compared to world data on femtoscopic radii in heavy-ion collisions. While the dependence is qualitatively similar to results at smaller √sNN, a decrease in the Rout/Rside ratio is seen, which is in qualitative agreement with specific predictions from hydrodynamic models. The results provide further evidence for the production of a collective, strongly coupled system in heavy-ion collisions at the LHC.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA