We report the first largely model independent measurement of charged particle multiplicities in quark and gluon jets, N(q) and N(g), produced at the Fermilab Tevatron in p (p) over bar collisions with a center-of-mass energy of 1.8 TeV and recorded by the Collider Detector at Fermilab. The measurements are made for jets with average energies of 41 and 53 GeV by counting charged particle tracks in cones with opening angles of theta(c)=0.28, 0.36, and 0.47 rad around the jet axis. The corresponding jet hardness Q=E(jet)theta(c) varies in the range from 12 to 25 GeV. At Q=19.2 GeV, the ratio of multiplicities r=N(g)/N(q) is found to be 1.64 +/- 0.17, where statistical and systematic uncertainties are added in quadrature. The results are in agreement with resummed perturbative QCD calculations.
Measurement of charged-particle multiplicities in gluon and quark jets in p(p)over-bar collisions at root s=1.8 TeV RID C-1693-2008 RID E-4473-2011
DELL'ORSO, MAURO;DONATI, SIMONE;PUNZI, GIOVANNI;
2005-01-01
Abstract
We report the first largely model independent measurement of charged particle multiplicities in quark and gluon jets, N(q) and N(g), produced at the Fermilab Tevatron in p (p) over bar collisions with a center-of-mass energy of 1.8 TeV and recorded by the Collider Detector at Fermilab. The measurements are made for jets with average energies of 41 and 53 GeV by counting charged particle tracks in cones with opening angles of theta(c)=0.28, 0.36, and 0.47 rad around the jet axis. The corresponding jet hardness Q=E(jet)theta(c) varies in the range from 12 to 25 GeV. At Q=19.2 GeV, the ratio of multiplicities r=N(g)/N(q) is found to be 1.64 +/- 0.17, where statistical and systematic uncertainties are added in quadrature. The results are in agreement with resummed perturbative QCD calculations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
