Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userVus determination from kaon decays
127
0
0.0
(
0
)
Authors
P. Massarotti
Ask ChatGPT about the research
No Arabic abstract
This review presents the analysis of leptonic and semileptonic kaon decays data done by the FlaviaNet Kaon Working group, as described in FlaviaNet Note of October 2008. Data include all recent results by BNL-E865, KLOE, KTeV, ISTRA+, and NA48. Experimental results are critically reviewed and combined, taking into account theoretical (both analytical and numerical) constraints on the semileptonic kaon form factors. We report on a very accurate determination of Vus as well as on many other tests of the SM which can be performed with leptonic and semileptonic kaon decays.
rate research
Read More
KLOE has measured most decay branching ratios of Ks, Kl and K+/- mesons. It has also measured the Kl and the K+- lifetime and determined the shape of the form factors involved in kaon semileptonic decays. We present in the following a description of the above measurements and a well organized compendium of all of our data, with particular attention to correlations. These data provide the basis for the determination of the CKM parameter Vus and a test of the unitarity of the quark flavor mixing matrix. We also test lepton universality and place bounds on new physics using measurements of Vus from Kl2 and Kl3 decays.
We present a global analysis of leptonic and semileptonic kaon decay data, including all recent results published by the BNL-E865, KLOE, KTeV, ISTRA+ and NA48 experiments. This analysis, in conjunction with precise lattice calculations of the hadronic matrix elements now available, leads to a very precise determination of |Vus| and allows us to perform several stringent tests of the Standard Model.
Precise measurements of semileptonic kaon decay rates at KLOE provide the measurement of the CKM mixing matrix element vus and information about lepton universality. Leptonic kaon decays provide an independent measurement of $abs{vus}^2/abs{vud}^2$, through the ratio $Gamma(Ktomu u)/Gamma(pitomu u)$. These measurements, together with the result of $|vud|$ from nuclear $beta$ transitions, provide the most precise test of CKM unitarity, allowing the universality of lepton and quark weak couplings to be tested. After the completion of the KLOE data taking, the proposal of a new run with an upgraded KLOE detector, KLOE-2, at an upgraded Dafne machine has been accepted by INFN and it is now starting. Present results from KLOE and future perspectives from KLOE-2 are reported.
While measuring the ratio R_K = Gamma(K+e2(gamma))/Gamma(K+mu2(gamma)), the KLOE Collaboration has studied the radiative process Ke2gamma. The ratio of the width for the Ke2gamma decay with a positively polarized photon from structure-dependent radiation to the inclusive Kmu2(gamma) width is found to be 1.484(68) 10-5. The observed radiation spectrum agrees with predictions from chiral perturbation theory and is in contrast with predictions based on the light front quark model. This result reduces the contribution to systematic uncertainties on measurements of R_K. In a separate study, KLOE has measured the ratio of the radiative Ke3gamma decay width to the inclusive Ke3(gamma) width to be 924(28) 10-5. The distribution in energy and angle of the radiative photon has been analyzed in an attempt to isolate the signature from interference of the inner-bremsstrahlung and structure-dependent amplitudes.
Recent NA48 results from detailed studies of $K_{L,S}to pi^+ pi^- e^+ e^-$ and $K_Stopi^0 gammagamma$ decay modes are presented. The results are based on the data collected with the NA48 detector at the CERN SPS during the 1998-199 9 and 2000 data taking periods, respectively. Prospects for future results on charged kaon decays are briefly described.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
