10 research outputs found
Measurement of the decay form factors in the OKA experiment
A precise measurement of the vector and axial-vector form factors difference
in the decay is presented.
About 95K events of are selected in
the OKA experiment. The result is .
Both errors are smaller than in the previous measurements.Comment: 9 pages, 8 figure
Searches for the light invisible axion-like particle in decay
A high statistics data sample of the decays is recorded by the OKA
collaboration. A missing mass analysis is performed to search for a light
invisible pseudoscalar axion-like particle (ALP) in the decay . No signal is observed, the upper limits for the branching
ratio of the decay are calculated. The confidence level upper limit is
changing from to for the ALP mass from 0 to
200 MeV/, except for the region of mass, where the upper limit
is .Comment: 6 pages, 6 figure
Observation of decay
The decay is observed by the OKA
collaboration. The branching ratio is measured to be . The branching ratio and energy spectrum are
consistent with ChPT prediction.Comment: arXiv admin note: text overlap with arXiv:2310.1642
Study of the decay in the OKA experiment
A high statistics data sample of the decays of mesons to three charged
particles was accumulated by the OKA experiment in 2012 and 2013. This allowed
to select a clean sample of about 450 events with
decays with the energy of the photon in
the kaon rest frame greater than 30 MeV. The measured branching fraction of the
, with > 30 MeV is . The measured energy spectrum of the decay photon is
compared with the prediction of the chiral perturbation theory to O. A
search for an up-down asymmetry of the photon with respect to the hadronic
system decay plane is also performed.Comment: 9 pages, 7 figures, 1 tabl
Observation of K + → π + π 0 π 0 γ decay
Abstract The K + → π + π 0 π 0 γ decay is observed by the OKA collaboration. About 60 events of the decay observed with signal:noise ≈ 1 . The branching ratio obtained by normalization to K + → π + π 0 π 0 is measured to be ( 3.7 ± 0.9 ( s t a t ) ± 0.3 ( s y s t ) ) × 10 - 6 for E γ ∗ > 10 MeV . The branching ratio, γ energy spectrum and angular distribution are consistent with ChPT prediction
Study of
Results of a study of the decay at OKA setup are presented. More than 32,000 events of this decay are observed. The differential spectra over the photon energy and the photon–electron opening angle in kaon rest frame are presented. The branching ratios, normalized to that of decay are calculated for different cuts on and . In particular, the branching ratio for MeV and is measured R = = = (0.587±0.010(stat.)±0.015(syst.)), which is in a good agreement with ChPT calculations
Search for heavy neutrino in K+→μ+νH decay
Abstract A high statistics data sample of the K+→μ+νμ decay was accumulated by the OKA experiment in 2012. The missing mass analysis was performed to search for the decay channel K+→μ+νH with a hypothetic stable heavy neutrino in the final state. The obtained missing mass spectrum does not show peaks that could be attributed to existence of stable heavy neutrinos in the mass range (270<mνH<375)  MeV /c2 . As a result, upper limits on the branching ratio and on the value of the mixing element |UμH|2 are obtained