![]() The vertical gray exclusion band is the current limit on the lightest neutrino masses from the cosmological data ∑ m i < 0.230 eV at 95% confidence level obtained by the Planck Collaboration. The present most stringent upper limits | m e e | < 0.120 eV from EXO-200 and KamLAND-ZEN are shown by a horizontal gray band. The first row corresponds to ( X l, X ν, P l, P ν ) = ( U, T, P 12, 1 ) on the left and ( X l, X ν, P l, P ν ) = ( U, T, P 12, P 12 ) on the right, the middle row is for ( X l, X ν, P l, P ν ) = ( U, S T S, P 12, 1 ), ( U, S T S, P 12, P 12 ), and the last row is for ( X l, X ν, P l, P ν ) = ( T 2, T, P 12, P 12 ). The residual flavor symmetry is ( G l, G ν ) = ( Z 2 S T 2 S U, Z 2 T U ) in this case. The red (blue) dashed lines indicate the most general allowed regions for the IH (NH) neutrino mass spectrum obtained by varying the mixing parameters over the 3 σ ranges. The predictions for the possible values of the effective Majorana mass | m e e | as a function of the lightest neutrino mass. We have studied the lepton mixing patterns arising from the flavor group S 4 and C P symmetry which are subsequently broken to all of the possible residual symmetries discussed in this work. We derive the most general criterion to determine whether two distinct residual symmetries lead to the same mixing pattern if the redefinition of the free parameters θ ν, l and θ 1, 2, 3 is taken into account. In the second scenario, an Abelian subgroup of the flavor group is preserved by the charged lepton mass matrix and the neutrino mass matrix is invariant under a single remnant C P transformation, all lepton mixing parameters are determined in terms of three free parameters θ 1, 2, 3. This type of breaking pattern is extended to the quark sector. The resulting lepton mixing matrix depends on two free parameters θ ν and θ l. In the first scenario, the flavor and C P symmetry is broken to the residual groups of the structure Z 2 × C P in the neutrino and charged lepton sectors. Karishma Borkakoty:Lepton Software: Leveraging Location Intelligence Through Map Based Analytics Products :Location analytics is creating buzz in new age. arXiv: 2212.We suggest two alternative schemes to predict lepton mixing angles as well as C P violating phases from a discrete flavor symmetry group combined with C P symmetry. Measurement of lepton universality parameters in B +→K +ℓ +ℓ − and B 0→K *0ℓ +ℓ − decays. Test of lepton universality in b→sℓ +ℓ − decays. “These results are compatible with the expectation of our theory.” “The results shown today are the product of a comprehensive study of the two main modes using our full data sample and applying new, more robust techniques.” “Measurements of the ratios of rare B-meson decays to electrons and muons have generated much interest in recent years because they are theoretically ‘clean’ and show consistency with a pattern of anomalies seen in other flavor processes,” said LHCb Collaboration spokesperson Professor Chris Parkes, a physicist at the University of Manchester and CERN. You will find details of church services, events, parish contacts and other useful information. The results, which supersede previous comparisons, are in excellent agreement with the principle of lepton flavor universality. Do take a look round the website, using the menu above. In addition, the two decay modes are measured in two different mass regions, thus yielding four independent comparisons of the decays. It considers two different B-meson decay modes simultaneously for the first time and provides better control of the background processes that can mimic the decays of B-mesons to electrons. The new LHCb analysis, which has been ongoing for the past five years, is more comprehensive. ![]() ![]() Interest in the ‘flavor anomalies’ peaked in March 2021, when LHCb presented new results comparing the rates at which certain B mesons, composite particles that contain beauty quarks, decay into muons and electrons.Īccording to the theory, decays involving muons and electrons should occur at the same rate, once differences in the leptons’ masses are accounted for.īut the LHCb results hinted that B mesons decay into muons at a lower rate than predicted, as indicated by the results’ statistical significance of 3.1 standard deviations from the Standard Model prediction. In recent years, however, an accumulation of results from LHCb and experiments in Japan and the United States have suggested that this might not be the case, generating cautious excitement among physicists that a more fundamental theory - perhaps one that sheds light on the Standard Model’s mysterious flavor structure - might reveal itself at the LHC. ![]() Lepton flavor universality states that the fundamental forces are blind to the generation to which a lepton belongs. Image credit: CERN.Ī central mystery of particle physics is why the 12 elementary quarks and leptons are arranged in pairs across three generations that are identical in all but mass, with ordinary matter comprising particles from the first, lightest generation. ![]()
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