Measurement of Kμ30 form factors
Abstract
This Letter reports on a new high precision measurement of the form factors of the K→πμν decay. The data sample of about 2.3×10 events was recorded in 1999 by the NA48 experiment at CERN. Studying the Dalitz plot density we measured a linear, λ+‧=(20.5±2.2±2.4)×10, and a quadratic, λ+″=(2.6±0.9±1.0)×10 term in the power expansion of the vector form factor. No evidence was found for a second order term for the scalar form factor; the linear slope was determined to be λ=(9.5±1.1±0.8)×10. Using a linear fit our results were: λ=(26.7±0.6±0.8)×10 and λ=(11.7±0.7±1.0)×10. A pole fit of the form factors yields: m=(905±9±17) MeV/c and m=(1400±46±53) MeV/c.
- Publication:
-
Physics Letters B
- Pub Date:
- April 2007
- DOI:
- 10.1016/j.physletb.2007.02.039
- arXiv:
- arXiv:hep-ex/0703002
- Bibcode:
- 2007PhLB..647..341N
- Keywords:
-
- 13.20.Eb;
- Decays of K mesons;
- High Energy Physics - Experiment
- E-Print:
- 22 pages 7 figures