Experimental physics

The European Physical Journal C - Particles and Fields

, Volume 14, Issue 4, pp 613-631

First online:

Measurement of the strange quark forward-backward asymmetry around the Z\(^{0}\) peak

  • The DELPHI Collaboration
  • , P. Abreu et al.Affiliated with LIP, IST, FCUL - Av. Elias Garcia, 14-1°, 1000 Lisboa Codex, Portugal

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


A precise measurement of the strange quark forward-backward asymmetry used 3.2M multihadronic events around the Z\(^0\) peak collected by the DELPHI experiment from 1992 to 1995. The ring imaging Cherenkov detectors in the barrel and end-cap regions identify high energy charged kaons which tag the s quark. The s quark asymmetry was measured at different centre-of-mass energies; in particular at the Z\(^0\) pole


taking the expected d and u quark asymmetries from the Standard Model. The quark flavour fractions are assumed from the Standard Model and the fragmentation process is modelled by JETSET. From the s quark pole asymmetry the electroweak mixing angle was determined:


The parity violating coupling of the s quark to the Z was determined to be: