Abstract
The decay rate of KL → π0 γγ has been measured with the NA48 detector at the CERN SPS. A total of 2558 KL π0γγ candidates have been observed with a residual background of 3.2%. The branching ratio is determined to be (1.36 ± 0.03(stat) ± 0.03(syst) ± 0.03(norm)) × 10-6 and the vector coupling constant av = -0.46 ± 0.03(stat) ± 0.04(syst). This result suggests that the CP-violation effects are dominating in the KL → π0e+e- decay. An upper limit for the KL → π0γγ decay rate in the two photon mass region mγγ < mπ0 is also given.
Lingua originale | Inglese |
---|---|
pagine (da-a) | 229-240 |
Numero di pagine | 12 |
Rivista | Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics |
Volume | 536 |
Numero di pubblicazione | 3-4 |
DOI | |
Stato di pubblicazione | Pubblicato - 6 giu 2002 |
Pubblicato esternamente | Sì |