| Hlavná stránka > L3 Preprints > Multiplicity fluctuations in L3 and QCD |
| Article | |
| Title | Multiplicity fluctuations in L3 and QCD |
| Author(s) | Chekanov, S V ; Kittel, E W ; Mangeol, D J J ; Metzger, W J |
| Affiliation | (CERN) |
| Collaboration | L3 Collaboration |
| Publication | 1999 |
| Imprint | 1999 |
| In: | 13th Lake Louise Winter Institute on Quantum Chromodynamics, Lake Louise, Canada, 15 - 21 Feb 1998, pp.412-21 |
| Subject category | Particle Physics - Experiment |
| Accelerator/Facility, Experiment | CERN LEP ; L3 |
| Abstract | Multiplicity fluctuations are studied both globally (in terms of high-order moments) and locally (in terms of small phase-space intervals). The ratio of cumulant factorial to factorial moments of the charged-particle multiplicity distribution shows a quasi- oscillatory behavior similar to that predicted by the NNLLA of perturbative QCD. However, an analysis of the sub-jet multiplicity distribution at perturbative scales shows that these oscillations cannot be related to the NNLLA prediction. We investigate how it is possible to reproduce the oscillations within the framework of Monte- Carlo models. Furthermore, local multiplicity fluctuations in angular phase-space intervals are compared with Monte-Carlo models and with first-order QCD predictions. While JETSET reproduces the experimental data very well, the predictions of DLLA and estimates obtained in MLLA deviate significantly from the data. (27 refs). |