Measurement of αs and the β function with the DELPHI detector at LEP

✍ Scribed by O. Prison

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 350 KB
• Volume: 121
• Category: Article
• ISSN: 0920-5632
• DOI: 10.1016/s0920-5632(03)01815-2

✦ Synopsis

Event shape distributions in e+e-annihilation are determined from the DELPHI data taken between 183 and 207GeV.

Fkom these the strong coupling crs is extracted with several techniques.

Together with the results from other LEP2 energies and at about ms this allows both, a combined measurement of a, and a test of the scale dependence of the strong interaction.

Alternatively the renormalisation group invariant (RGI) perturbation theory is applied to measure the ,L3 function of strong interaction.

The results are good agreement with the QCD expectation and allow to exclude the existence of light gluinos with a mass below 30 GeV in a model independent way.