Phys. Rev. D 74, 032004 (2006) [5 pages]Measurement of direct photon emission in the KL→π+π-γ decay modeSee Also: Publisher's Note Received 17 March 2006; published 8 August 2006; corrected 9 August 2006 In this paper the KTeV collaboration reports the analysis of 112.1×103 candidate KL→π+π-γ decays including a background of 671±41 events with the objective of determining the photon production mechanisms intrinsic to the decay process. These decays have been analyzed to extract the relative contributions of the CP violating bremsstrahlung process and the CP conserving M1 and CP violating E1 direct photon emission processes. The M1 direct photon emission amplitude and its associated vector form factor parameterized as |g˜M1|(1+a1/a2/(Mρ2-MK2)+2MKEγ) have been measured to be |g˜M1|=1.198±0.035(stat)±0.086(syst) and a1/a2=-0.738±0.007(stat)±0.018(syst) GeV2/c2 respectively. An upper limit for the CP violating E1 direct emission amplitude |gE1|≤0.21 (90%CL) has been found. The overall ratio of direct photon emission (DE) to total photon emission including the bremsstrahlung process (IB) has been determined to be DE/(DE+IB)=0.689±0.021 for Eγ≥20 MeV. © 2006 The American Physical Society URL:
http://link.aps.org/doi/10.1103/PhysRevD.74.032004
DOI:
10.1103/PhysRevD.74.032004
PACS:
13.20.Eb, 11.30.Er, 13.25.Es, 13.40.Hq
See AlsoPublisher's Note: E. Abouzaid et al., Publisher’s Note: Measurement of direct photon emission in the KL→π+π-γ decay mode [Phys. Rev. D 74, 032004 (2006)], Phys. Rev. D 74, 039905 (2006). |
|
About | Terms and Conditions | Subscriptions | Search | Help
Use of the American Physical Society websites and journals implies that the user has read and agrees to our Terms and Conditions and any applicable Subscription Agreement. Physical Review®, Physical Review Letters®, Reviews of Modern Physics®, and Physical Review Special Topics® are trademarks of the American Physical Society.