Published December 2009 | Version v1
Journal article

Precise measurement of Γ(K→e ν(γ))/Γ(K→μ ν(γ)) and study of K→e ν γ

  • 1. INFN Sezione di Napoli, Napoli (Italy)
  • 2. Dipartimento di Scienze Fisiche dell'Universita ''Federico II'', Napoli (Italy)
  • 3. Laboratori Nazionali di Frascati dell'INFN, Frascati (Italy)
  • 4. INFN Sezione di Roma Tor Vergata, Rome (Italy)
  • 5. Dipartimento di Fisica dell'Universita ''Tor Vergata'', Rome (Italy)
  • 6. Johannes Gutenberg-Universitaet, Institut fuer Kernphysik, Mainz (Germany)
  • 7. INFN Sezione di Roma, Rome (Italy)
  • 8. Dipartimento di Fisica dell'Universita ''La Sapienza'', Rome (Italy)
  • 9. INFN Sezione di Roma Tre, Rome (Italy)
  • 10. Dipartimento di Fisica dell'Universita ''Roma Tre'', Rome (Italy)
  • 11. Institute for Theoretical and Experimental Physics, Moscow (Russian Federation)
  • 12. State University of New York, Physics Department, Stony Brook (United States)
  • 13. Dipartimento di Energetica dell'Universita ''La Sapienza'', Rome (Italy)

Description

We present a precise measurement of the ratio RK=Γ(K→eν(γ))/Γ(K→μν(γ)) and a study of the radiative process K→eνγ, performed with the KLOE detector. The results are based on data collected at the Frascati e+e- collider DA ΦNE for an integrated luminosity of 2.2 fb-1. We find RK=(2.493±0.025stat±0.019syst) x 10-5, in agreement with the Standard Model expectation. This result is used to improve constraints on parameters of the Minimal Supersymmetric Standard Model with lepton flavor violation. We also measured the differential decay rate d Γ(K→eνγ)/dEγ for photon energies 10<Eγ<250 MeV. Results are compared with predictions from theory. (orig.)

Availability note (English)

Available from: http://dx.doi.org/10.1140/epjc/s10052-009-1177-x

Additional details

Publishing Information

Journal Title
European Physical Journal. C
Journal Volume
64
Journal Issue
4
Journal Page Range
p. 627-636
ISSN
1434-6044

Optional Information

Collaborations
KLOE Collaboration