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In this Report, QCD results obtained from a study of hadronic event structure in high energy e^+e^- interactions with the L3 detector are presented. The operation of the LEP collider at many different collision energies from 91 GeV to 209 GeV offers a unique opportunity to test QCD by measuring the energy dependence of different observables. The main results concern the measurement of the strong coupling constant, \alpha_s, from hadronic event shapes and the study of effects of soft gluon coherence through charged particle multiplicity and momentum distributions.
Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 130.1 GeV.
Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 136.1 GeV.
Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 161.3 GeV.
Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 172.3 GeV.
Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 182.8 GeV.
Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 188.6 GeV.
Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 194.4 GeV.
Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 200.2 GeV.
Jet fractions using the JADE algorithm as a function of the jet resolution parameter YCUT at c.m. energy 206.2 GeV.
Jet fractions using the KT(Durham) algorithm as a function of the jet resolution parameter YCUT at c.m. energy 130.1 GeV.
Jet fractions using the KT(Durham) algorithm as a function of the jet resolution parameter YCUT at c.m. energy 136.1 GeV.
Jet fractions using the KT(Durham) algorithm as a function of the jet resolution parameter YCUT at c.m. energy 161.3 GeV.
Jet fractions using the KT(Durham) algorithm as a function of the jet resolution parameter YCUT at c.m. energy 172.3 GeV.
Jet fractions using the KT(Durham) algorithm as a function of the jet resolution parameter YCUT at c.m. energy 182.8 GeV.
Jet fractions using the KT(Durham) algorithm as a function of the jet resolution parameter YCUT at c.m. energy 188.6 GeV.
Jet fractions using the KT(Durham) algorithm as a function of the jet resolution parameter YCUT at c.m. energy 194.4 GeV.
Jet fractions using the KT(Durham) algorithm as a function of the jet resolution parameter YCUT at c.m. energy 200.2 GeV.
Jet fractions using the KT(Durham) algorithm as a function of the jet resolution parameter YCUT at c.m. energy 206.2 GeV.
Jet fractions using the Cambridge algorithm as a function of the jet resolution parameter YCUT at c.m. energy 202.2 GeV.
Jet fractions using the Cambridge algorithm as a function of the jet resolution parameter YCUT at c.m. energy 206.2 GeV.
Differential distributions for event thrust.
Differential distributions for event thrust.
Differential distributions for event thrust.
Differential distributions for event thrust.
Differential distributions for event thrust.
Differential distributions for the scaled heavy jet mass (RHO(C=HEAVY)).
Differential distributions for the scaled heavy jet mass (RHO(C=HEAVY)).
Differential distributions for the scaled heavy jet mass (RHO(C=HEAVY)).
Differential distributions for the scaled heavy jet mass (RHO(C=HEAVY)).
Differential distributions for the scaled heavy jet mass (RHO(C=HEAVY)).
Differential distributions for total jet broadening (BT).
Differential distributions for total jet broadening (BT).
Differential distributions for total jet broadening (BT).
Differential distributions for total jet broadening (BT).
Differential distributions for total jet broadening (BT).
Differential distributions for wide jet broadening (BW).
Differential distributions for wide jet broadening (BW).
Differential distributions for wide jet broadening (BW).
Differential distributions for wide jet broadening (BW).
Differential distributions for wide jet broadening (BW).
Differential distributions for the C-Parameter.
Differential distributions for the C-Parameter.
Differential distributions for the C-Parameter.
Differential distributions for the D-Parameter.
Differential distributions for the D-Parameter.
Differential distributions for the D-Parameter.
Differential distributions for the THRUST at c.m. energy 91.2 GeV for light quark (udsc) and b quark events.
Differential distributions for the RHO(C=HEAVY) at c.m. energy 91.2 GeV forlight quark (udsc) and b quark events.
Differential distributions for the BT at c.m. energy 91.2 GeV for light quark (udsc) and b quark events.
Differential distributions for the BW at c.m. energy 91.2 GeV for light quark (udsc) and b quark events.
Differential distributions for the C-PARAM at c.m. energy 91.2 GeV for light quark (udsc) and b quark events.
Differential distributions for the D-PARAM at c.m. energy 91.2 GeV for light quark (udsc) and b quark events.
Mean values (first moment) and dispersion (second moment) of the THRUST distribution as a function of c.m. energy.
Mean values (first moment) and dispersion (second moment) of the scaled heavy jet mass (RHO(C=HEAVY)) as a function of c.m. energy.
Mean values (first moment) and dispersion (second moment) of the total jet broadening (BT) as a function of c.m. energy.
Mean values (first moment) and dispersion (second moment) of the wide jet broadening (BW) as a function of c.m. energy.
Mean values (first moment) and dispersion (second moment) of the C-PARAM as a function of c.m. energy.
Mean values (first moment) and dispersion (second moment) of the D-PARAM as a function of c.m. energy.
Charged particle multiplicities at c.m. energy 91.2 GeV for all flavour, light quark (udsc) and bottom (b) flavour events.
Charged particle multiplicity.
Charged particle multiplicity.
Charged particle multiplicity.
First and second moment of the charged particle multiplicity distribution at c.m. energy 91.2 GeV for all flavours and for udsc an b flavours.
First and second moment of the charged particle multiplicity distribution at c.m. energy.
Distribution of LN(1/X) at c.m. energy 91.2 GeV.
Distribution of LN(1/X) at higher c.m. energies.
Distribution of LN(1/X) at higher c.m. energies.
Distribution of LN(1/X) at higher c.m. energies.
The hadronic final states observed with the ALEPH detector at LEP in ${\rm e}^ + {\rm e}^-$ annihilation
Mean charged particle multiplicities at different c.m. energies.
XP distribution at c.m. energy 133.0 GeV.
XP distribution at c.m. energy 161.0 GeV.
XP distribution at c.m. energy 172.0 GeV.
XP distribution at c.m. energy 183.0 GeV.
XP distribution at c.m. energy 189.0 GeV.
XP distribution at c.m. energy 196.0 GeV.
XP distribution at c.m. energy 200.0 GeV.
XP distribution at c.m. energy 206.0 GeV.
Peak position in XI distribution for different c.m. energies.
XI distribution at c.m. energy 133.0 GeV.
XI distribution at c.m. energy 161.0 GeV.
XI distribution at c.m. energy 172.0 GeV.
XI distribution at c.m. energy 183.0 GeV.
XI distribution at c.m. energy 189.0 GeV.
XI distribution at c.m. energy 196.0 GeV.
XI distribution at c.m. energy 200.0 GeV.
XI distribution at c.m. energy 206.0 GeV.
XE distribution at c.m. energy 133.0 GeV.
XE distribution at c.m. energy 161.0 GeV.
XE distribution at c.m. energy 172.0 GeV.
XE distribution at c.m. energy 183.0 GeV.
XE distribution at c.m. energy 189.0 GeV.
XE distribution at c.m. energy 196.0 GeV.
XE distribution at c.m. energy 200.0 GeV.
XE distribution at c.m. energy 206.0 GeV.
PTIN distribution at c.m. energy 133.0 GeV.
PTIN distribution at c.m. energy 161.0 GeV.
PTIN distribution at c.m. energy 172.0 GeV.
PTIN distribution at c.m. energy 183.0 GeV.
PTIN distribution at c.m. energy 189.0 GeV.
PTIN distribution at c.m. energy 196.0 GeV.
PTIN distribution at c.m. energy 200.0 GeV.
PTIN distribution at c.m. energy 206.0 GeV.
PTOUT distribution at c.m. energy 206.0 GeV.
RAPIDITY W.R.T THRUST AXIS distribution at c.m. energy 133.0 GeV.
RAPIDITY W.R.T THRUST AXIS distribution at c.m. energy 161.0 GeV.
RAPIDITY W.R.T THRUST AXIS distribution at c.m. energy 172.0 GeV.
RAPIDITY W.R.T THRUST AXIS distribution at c.m. energy 183.0 GeV.
RAPIDITY W.R.T THRUST AXIS distribution at c.m. energy 189.0 GeV.
RAPIDITY W.R.T THRUST AXIS distribution at c.m. energy 196.0 GeV.
RAPIDITY W.R.T THRUST AXIS distribution at c.m. energy 200.0 GeV.
RAPIDITY W.R.T THRUST AXIS distribution at c.m. energy 206.0 GeV.
RAPIDITY W.R.T. SPHERICITY AXIS distribution at c.m. energy 133.0 GeV.
RAPIDITY W.R.T. SPHERICITY AXIS distribution at c.m. energy 161.0 GeV.
RAPIDITY W.R.T. SPHERICITY AXIS distribution at c.m. energy 172.0 GeV.
RAPIDITY W.R.T. SPHERICITY AXIS distribution at c.m. energy 183.0 GeV.
RAPIDITY W.R.T. SPHERICITY AXIS distribution at c.m. energy 189.0 GeV.
RAPIDITY W.R.T. SPHERICITY AXIS distribution at c.m. energy 196.0 GeV.
RAPIDITY W.R.T. SPHERICITY AXIS distribution at c.m. energy 200.0 GeV.
RAPIDITY W.R.T. SPHERICITY AXIS distribution at c.m. energy 206.0 GeV.
Combined results for ALPHAS.
Event shape means.
THRUST distribution at c.m. energy 91.20 GeV.
1-THRUST distribution at c.m. energy 133.00 GeV.
1-THRUST distribution at c.m. energy 161.00 GeV.
1-THRUST distribution at c.m. energy 172.00 GeV.
1-THRUST distribution at c.m. energy 183.00 GeV.
1-THRUST distribution at c.m. energy 189.00 GeV.
1-THRUST distribution at c.m. energy 200.00 GeV.
1-THRUST distribution at c.m. energy 206.00 GeV.
Heavy Jet Mass (RHO) distribution at c.m. energy 91.20 GeV.
Heavy Jet Mass (RHO) distribution at c.m. energy 133.00 GeV.
Heavy Jet Mass (RHO) distribution at c.m. energy 161.00 GeV.
Heavy Jet Mass (RHO) distribution at c.m. energy 172.00 GeV.
Heavy Jet Mass (RHO) distribution at c.m. energy 183.00 GeV.
Heavy Jet Mass (RHO) distribution at c.m. energy 189.00 GeV.
Heavy Jet Mass (RHO) distribution at c.m. energy 200.00 GeV.
Heavy Jet Mass (RHO) distribution at c.m. energy 206.00 GeV.
Total jet broadening distribution at c.m. energy 91.20 GeV.
Total jet broadening distribution at c.m. energy 133.00 GeV.
Total jet broadening distribution at c.m. energy 161.00 GeV.
Total jet broadening distribution at c.m. energy 172.00 GeV.
Total jet broadening distribution at c.m. energy 183.00 GeV.
Total jet broadening distribution at c.m. energy 189.00 GeV.
Total jet broadening distribution at c.m. energy 200.00 GeV.
Total jet broadening distribution at c.m. energy 206.00 GeV.
Wide jet broadening distribution at c.m. energy 91.20 GeV.
Wide jet broadening distribution at c.m. energy 133.00 GeV.
Wide jet broadening distribution at c.m. energy 161.00 GeV.
Wide jet broadening distribution at c.m. energy 172.00 GeV.
Wide jet broadening distribution at c.m. energy 183.00 GeV.
Wide jet broadening distribution at c.m. energy 189.00 GeV.
Wide jet broadening distribution at c.m. energy 200.00 GeV.
Wide jet broadening distribution at c.m. energy 206.00 GeV.
C-PARAMETER distribution at c.m. energy 91.20 GeV.
C-PARAMETER distribution at c.m. energy 133.00 GeV.
C-PARAMETER distribution at c.m. energy 161.00 GeV.
C-PARAMETER distribution at c.m. energy 172.00 GeV.
C-PARAMETER distribution at c.m. energy 183.00 GeV.
C-PARAMETER distribution at c.m. energy 189.00 GeV.
C-PARAMETER distribution at c.m. energy 200.00 GeV.
C-PARAMETER distribution at c.m. energy 206.00 GeV.
Thrust Major distribution at c.m. energy 91.20 GeV.
Thrust Major distribution at c.m. energy 133.00 GeV.
Thrust Major distribution at c.m. energy 161.00 GeV.
Thrust Major distribution at c.m. energy 172.00 GeV.
Thrust Major distribution at c.m. energy 183.00 GeV.
Thrust Major distribution at c.m. energy 189.00 GeV.
Thrust Major distribution at c.m. energy 200.00 GeV.
Thrust Major distribution at c.m. energy 206.00 GeV.
Thrust Minor distribution at c.m. energy 91.20 GeV.
Thrust Minor distribution at c.m. energy 133.00 GeV.
Thrust Minor distribution at c.m. energy 161.00 GeV.
Thrust Minor distribution at c.m. energy 172.00 GeV.
Thrust Minor distribution at c.m. energy 183.00 GeV.
Thrust Minor distribution at c.m. energy 189.00 GeV.
Thrust Minor distribution at c.m. energy 200.00 GeV.
Thrust Minor distribution at c.m. energy 206.00 GeV.
Jet Mass Difference distribution at c.m. energy 91.20 GeV.
Jet Mass Difference distribution at c.m. energy 133.00 GeV.
Jet Mass Difference distribution at c.m. energy 161.00 GeV.
Jet Mass Difference distribution at c.m. energy 172.00 GeV.
Jet Mass Difference distribution at c.m. energy 183.00 GeV.
Jet Mass Difference distribution at c.m. energy 189.00 GeV.
Jet Mass Difference distribution at c.m. energy 200.00 GeV.
Jet Mass Difference distribution at c.m. energy 206.00 GeV.
Aplanarity distribution at c.m. energy 91.20 GeV.
Aplanarity distribution at c.m. energy 133.00 GeV.
Aplanarity distribution at c.m. energy 161.00 GeV.
Aplanarity distribution at c.m. energy 172.00 GeV.
Aplanarity distribution at c.m. energy 183.00 GeV.
Aplanarity distribution at c.m. energy 189.00 GeV.
Aplanarity distribution at c.m. energy 200.00 GeV.
Aplanarity distribution at c.m. energy 206.00 GeV.
Planarity distribution at c.m. energy 133.00 GeV.
Planarity distribution at c.m. energy 161.00 GeV.
Planarity distribution at c.m. energy 172.00 GeV.
Planarity distribution at c.m. energy 183.00 GeV.
Planarity distribution at c.m. energy 189.00 GeV.
Planarity distribution at c.m. energy 200.00 GeV.
Planarity distribution at c.m. energy 206.00 GeV.
Oblateness distribution at c.m. energy 91.20 GeV.
Oblateness distribution at c.m. energy 133.00 GeV.
Oblateness distribution at c.m. energy 161.00 GeV.
Oblateness distribution at c.m. energy 172.00 GeV.
Oblateness distribution at c.m. energy 183.00 GeV.
Oblateness distribution at c.m. energy 189.00 GeV.
Oblateness distribution at c.m. energy 200.00 GeV.
Oblateness distribution at c.m. energy 206.00 GeV.
Sphericity distribution at c.m. energy 91.20 GeV.
Sphericity distribution at c.m. energy 133.00 GeV.
Sphericity distribution at c.m. energy 161.00 GeV.
Sphericity distribution at c.m. energy 172.00 GeV.
Sphericity distribution at c.m. energy 183.00 GeV.
Sphericity distribution at c.m. energy 189.00 GeV.
Sphericity distribution at c.m. energy 200.00 GeV.
Sphericity distribution at c.m. energy 206.00 GeV.
LN(Y12) distribution at c.m. energy 91.20 GeV.
LN(Y12) distribution at c.m. energy 133.00 GeV.
LN(Y12) distribution at c.m. energy 161.00 GeV.
LN(Y12) distribution at c.m. energy 172.00 GeV.
LN(Y12) distribution at c.m. energy 183.00 GeV.
LN(Y12) distribution at c.m. energy 189.00 GeV.
LN(Y12) distribution at c.m. energy 200.00 GeV.
LN(Y12) distribution at c.m. energy 206.00 GeV.
LN(Y23) distribution at c.m. energy 91.20 GeV.
LN(Y23) distribution at c.m. energy 133.00 GeV.
LN(Y23) distribution at c.m. energy 161.00 GeV.
LN(Y23) distribution at c.m. energy 172.00 GeV.
LN(Y23) distribution at c.m. energy 183.00 GeV.
LN(Y23) distribution at c.m. energy 189.00 GeV.
LN(Y23) distribution at c.m. energy 200.00 GeV.
LN(Y23) distribution at c.m. energy 206.00 GeV.
LN(Y34) distribution at c.m. energy 91.20 GeV.
LN(Y34) distribution at c.m. energy 133.00 GeV.
LN(Y34) distribution at c.m. energy 161.00 GeV.
LN(Y34) distribution at c.m. energy 172.00 GeV.
LN(Y34) distribution at c.m. energy 183.00 GeV.
LN(Y34) distribution at c.m. energy 189.00 GeV.
LN(Y34) distribution at c.m. energy 200.00 GeV.
LN(Y34) distribution at c.m. energy 206.00 GeV.
LN(Y45) distribution at c.m. energy 91.20 GeV.
LN(Y45) distribution at c.m. energy 133.00 GeV.
LN(Y45) distribution at c.m. energy 161.00 GeV.
LN(Y45) distribution at c.m. energy 172.00 GeV.
LN(Y45) distribution at c.m. energy 183.00 GeV.
LN(Y45) distribution at c.m. energy 189.00 GeV.
LN(Y45) distribution at c.m. energy 206.00 GeV.
LN(Y56) distribution at c.m. energy 91.20 GeV.
LN(Y56) distribution at c.m. energy 133.00 GeV.
LN(Y56) distribution at c.m. energy 161.00 GeV.
LN(Y56) distribution at c.m. energy 172.00 GeV.
LN(Y56) distribution at c.m. energy 183.00 GeV.
LN(Y56) distribution at c.m. energy 189.00 GeV.
LN(Y56) distribution at c.m. energy 206.00 GeV.
1-jet fraction at c.m. energy 91.20 GeV.
1-jet fraction at c.m. energy 133.00 GeV.
1-jet fraction at c.m. energy 161.00 GeV.
1-jet fraction at c.m. energy 172.00 GeV.
1-jet fraction at c.m. energy 183.00 GeV.
1-jet fraction at c.m. energy 189.00 GeV.
1-jet fraction at c.m. energy 200.00 GeV.
1-jet fraction at c.m. energy 206.00 GeV.
2-jet fraction at c.m. energy 91.20 GeV.
2-jet fraction at c.m. energy 133.00 GeV.
2-jet fraction at c.m. energy 161.00 GeV.
2-jet fraction at c.m. energy 172.00 GeV.
2-jet fraction at c.m. energy 183.00 GeV.
2-jet fraction at c.m. energy 189.00 GeV.
2-jet fraction at c.m. energy 200.00 GeV.
2-jet fraction at c.m. energy 206.00 GeV.
3-jet fraction at c.m. energy 91.20 GeV.
3-jet fraction at c.m. energy 133.00 GeV.
3-jet fraction at c.m. energy 161.00 GeV.
3-jet fraction at c.m. energy 172.00 GeV.
3-jet fraction at c.m. energy 183.00 GeV.
3-jet fraction at c.m. energy 189.00 GeV.
3-jet fraction at c.m. energy 200.00 GeV.
3-jet fraction at c.m. energy 206.00 GeV.
4-jet fraction at c.m. energy 91.20 GeV.
4-jet fraction at c.m. energy 133.00 GeV.
4-jet fraction at c.m. energy 161.00 GeV.
4-jet fraction at c.m. energy 172.00 GeV.
4-jet fraction at c.m. energy 183.00 GeV.
4-jet fraction at c.m. energy 189.00 GeV.
4-jet fraction at c.m. energy 200.00 GeV.
4-jet fraction at c.m. energy 206.00 GeV.
5-jet fraction at c.m. energy 91.20 GeV.
5-jet fraction at c.m. energy 133.00 GeV.
5-jet fraction at c.m. energy 161.00 GeV.
5-jet fraction at c.m. energy 172.00 GeV.
5-jet fraction at c.m. energy 183.00 GeV.
5-jet fraction at c.m. energy 189.00 GeV.
5-jet fraction at c.m. energy 200.00 GeV.
5-jet fraction at c.m. energy 206.00 GeV.
>=6-jet fraction at c.m. energy 91.20 GeV.
>=6-jet fraction at c.m. energy 133.00 GeV.
>=6-jet fraction at c.m. energy 161.00 GeV.
>=6-jet fraction at c.m. energy 172.00 GeV.
>=6-jet fraction at c.m. energy 183.00 GeV.
>=6-jet fraction at c.m. energy 189.00 GeV.
>=6-jet fraction at c.m. energy 200.00 GeV.
>=6-jet fraction at c.m. energy 206.00 GeV.
We present results obtained from a study of the structure of hadronic events recorded by the L3 detector at various centre-of-mass energies. The distributions of event shape variables and the energy dependence of their mean values are measured from 30GeV to 189GeV and compared with various QCD models. The energy dependence of the moments of event shape variables is used to test a power law ansatz for the non-perturbative component. We obtain a universal value of the non-perturbative parameter alpha_0 = 0.537 +/- 0.073. From a comparison with resummed O(alpha_s^2) QCD calculations, we determine the strong coupling constant at each of the selected energies. The measurements demonstrate the running of alpha_s as expected in QCD with a value of alpha_s(m_Z) = 0.1215 +/- 0.0012 (exp) +/- 0.0061 (th).
Distribution for THRUST at c.m. energy 189 GeV.
Distribution for Heavy Jet Mass at c.m. energy 189 GeV.
Distribution for Total Jet Broadening at c.m. energy 189 GeV.
Distribution for Wide Jet Broadening at c.m. energy 189 GeV.
Distribution for C-Parameter at c.m. energy 189 GeV.
Mean values (first moments) of the 1-THRUST distributions as a function of c.m. energy.
Mean values (first moments) of the Heavy Jet Mass distributions as a function of c.m. energy.
Mean values (first moments) of the Total Jet Broadening distributions as a function of c.m. energy.
Mean values (first moments) of the Wide Jet Broadening distributions as a function of c.m. energy.
Mean values (first moments) of the C-Parameter distributions as a function of c.m. energy.
Dispersion values (second moments) of the 1-THRUST distributions as a function of c.m. energy.
Dispersion values (second moments) of the Heavy Jet Mass distributions as afunction of c.m. energy.
Dispersion values (second moments) of the Total Jet Broadening distributions as a function of c.m. energy.
Dispersion values (second moments) of the Wide Jet Broadening distributionsas a function of c.m. energy.
Dispersion values (second moments) of the C-Parameter distributions as a function of c.m. energy.
Values of the strong coupling constant ALPHA-s at the Z0 mass, from fits tothe first moments of the various event shape distribution.
The strong coupling constant, ALPHA-s, measured at different c.m. energies from a fit to the 1-THRUST distribution. The second DSYS error is the uncertainty in the theory.
The strong coupling constant, ALPHA-s, measured at different c.m. energies from a fit to the Heavy Jet Mass distribution. The second DSYS error is the uncertainty in the theory.
The strong coupling constant, ALPHA-s, measured at different c.m. energies from a fit to the Total Jet Broadening distribution. The second DSYS error is the uncertainty in the theory.
The strong coupling constant, ALPHA-s, measured at different c.m. energies from a fit to the Wide Jet Broadening distribution. The second DSYS error is theuncertainty in the theory.
The strong coupling constant, ALPHA-s, measured at different c.m. energies from a fit to the C-Parameter distribution. The second DSYS error is the uncertainty in the theory.
The strong coupling constant, ALPHA-s, as determined from the combined event shape variables as a function of c.m. energy. The values for c.m. energy belowthe Z0 mass were determined only for four event shape variables.
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