Marinova, E. (2010) K rare decays with NA62. Il nuovo cimento C, 33 (5). pp. 213-220. ISSN 1826-9885
|
Text
ncc9730.pdf - Published Version Download (516kB) | Preview |
Abstract
The long-term goal of NA62 is to measure the ultra rare K ± → π ± ν¯ν decay with a sensitivity of 10−12 per event. This is done by using the decay-in-flight technique which allows a signal acceptance of ∼ 10%. The aim is to collect about 100 signal events in two years of data taking with a background-to-signal ratio smaller than 10%. The principle of the experimental measurement and the layout of the detector are presented. During 2007/2008 a dedicated run devoted to NA62 prototype tests and study of Ke2 decays was taken. The first phase of the NA62 experiment is aiming at a high-precision test of the lepton universality by measuring the helicity suppressed ratio RK. The preliminary result based on 40% of the 2007 NA62 data sample, RK = Ke2/Kμ2 = (2.500 ± 0.016) × 10−5, which is the first result with a precision better than 1%, is consistent with the Standard Model. Aiming at charge asymmetry measurements, the NA48/2 experiment collected an unprecedented amount of charged K3π events. The large samples allowed a precision measurement of rare charged kaon decays. New measurements of the K ± π�� decays based on the full NA48/2 data sample collected during 2003/2004 are reported in this paper. Samples of about 7200 reconstructed K ± → π ± e+e− events, and more than 3000 K ± → π ± μ+μ− events, with a few percent background contamination, have been collected. A precise measurement of the branching fractions and the form factors of the rare decays K ± π�� were performed. Measurements of the CP-violating and the forward-backward asymmetries are reported.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | Decays of K mesons ; Flavor symmetries ; Neutral currents |
| Subjects: | 500 Scienze naturali e Matematica > 530 Fisica |
| Depositing User: | Marina Spanti |
| Date Deposited: | 02 Apr 2020 14:57 |
| Last Modified: | 02 Apr 2020 14:57 |
| URI: | http://eprints.bice.rm.cnr.it/id/eprint/17057 |
Actions (login required)
 |
View Item |
