A new measurement of the properties of the rare decay K -> pi+ e+ e-
| dc.creator | Appel, R. | |
| dc.date | 1999-07-22 | |
| dc.date.accessioned | 2026-07-07T10:51:54Z | |
| dc.date.available | 2026-07-07T10:51:54Z | |
| dc.description | A large low-background sample of events (10300) has been collected for the rare decay of kaons in flight K+ -> pi+ e+ e- by experiment E865 at the Brookhaven AGS. The decay products were accepted by a broad band high-resolution charged particle spectrometer with particle identification. The branching ratio (2.94 +- 0.05(stat.) +- 0.13(syst.) +- 0.05(model))*10**{-7} was determined normalizing to events from the decay chain K+ -> pi+ pi0; pi0 -> e+ e- gamma. From the analysis of the decay distributions the vector nature of this decay is firmly established now, and limits on scalar and tensor contributions are deduced. From the (e+ e-) invariant mass distribution the decay form factor f(z)=f0(1+ delta*z) (z=M(ee)**2/m(K)**2) is determined with delta=2.14 +- 0.13 +- 0.15. Chiral QCD perturbation theory predictions for the form factor are also tested, and terms beyond leading order O(p**4) are found to be important. | |
| dc.description | 4 pages, 5 figures | |
| dc.identifier | https://arxiv.org/abs/hep-ex/9907045 | |
| dc.identifier | http://arxiv.org/abs/hep-ex/9907045 | |
| dc.identifier | Phys.Rev.Lett.83:4482-4485,1999 | |
| dc.identifier | doi:10.1103/PhysRevLett.83.4482 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/184980 | |
| dc.subject | High Energy Physics - Experiment | |
| dc.title | A new measurement of the properties of the rare decay K -> pi+ e+ e- | |
| dc.type | text |