454 research outputs found
Event shape studies, and its running from LEP
No full textData from electron positron annihilations at different center of mass energies are collected by the four LEP experiments. Direct tests of hard QCD are performed by measuring and analysing event shape observables
Measurements of with the DELPHI detector at LEP
No full textThe data collected with DELPHI during the LEP1 period is used to perform a simultaneous fit to the strong coupling constant alpha /sub s/ in 2/sup nd/ order perturbation theory and to the renormalisation scale x/sub mu /. The results are compared to alpha /sub s/ fits in 2 /sup nd/ order perturbation theory with fixed scale x/sub mu / and to other theoretically motivated scale setting methods. To determine the energy dependence of alpha /sub s/, event shape distributions and their mean values are measured for square root (s)=48 GeV to 189 GeV. The strong coupling alpha /sub s/ is extracted in O( alpha /sub s //sup 2/). Next to leading log approximation (NLLA) and in a combined scheme using - evaluated with fragmentation model generators, and an analytical power ansatz. (16 refs)
A study of the energy evolution of event shape distributions and their means with the DELPHI detector at LEP
No full text
QCD Results from the DELPHI Measurements of Event Shape and Inclusive Particle Distributions at
No full textthe highest LEP energie
QCD results from the DELPHI measurements of event shape and inclusive particle distributions between 48 GeV and 189 GeV
No full text- …
