Forward-backward multiplicity correlations in pp collisions at s = 0.9, 2.76 and 7 TeV

20 May 2014, 16:30
2h
spectrum (darmstadtium)

spectrum

darmstadtium

Board: I-03
Poster Correlations and Fluctuations Poster session

Speakers

Igor Altsybeev (St. Petersburg State University (RU)) Sudipan De (Department of Atomic Energy (IN))

Description

Forward-backward multiplicity correlations have been measured with the ALICE detector at the LHC in pp minimum bias collisions at s = 0.9, 2.76 and 7 TeV. The measurement is performed in the central pseudorapidity region (|η|<0.8) for pT>0.3 GeV/c. The multiplicity correlation strength (bcorr) was obtained using pairs of separate pseudorapidity and azimuthal windows and studied as a function of the separation distance between the windows in η and φ, as well as of the size of the windows. A considerable increase of the correlation strength with the collision energy is found. Two types of contributions -- the short-range (SR) and the long-range (LR) -- are observed. The energy dependence of bcorr is found to be weak for the SR component and strong for the LR component. The bcorr is also studied in different transverse momentum intervals, which have the same mean multiplicity. It is found that both SR and LR contributions to bcorr increase with increasing minimum threshold of pT. The results are compared to PYTHIA and PHOJET Monte Carlo event generators and to the string-based empirical model.
On behalf of collaboration: ALICE

Primary authors

Igor Altsybeev (St. Petersburg State University (RU)) Sudipan De (Department of Atomic Energy (IN))

Presentation materials