The Journey of Petterson 130

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In this article I investigated some of the mid-level and developing automobile websites from US and derived their Search Engine Optimization (SEO) indices and trends. Theorists have calculated that, in the Standard Model, this decay should occur about 3 times in every billion, but that if new particles predicted by theories such as supersymmetry exist, the decay could occur much more often (see news items of 8 April and 22 July 2011 for more details).
Since lifetime measurements of hadrons containing heavy quarks are sensitive to the internal structure and dynamics within those hadrons, today's precision measurement by LHCb apratamaa.mhs.uksw.edu will stimulate even more interest in charmed-baryon lifetime measurements as well as renewed theoretical efforts to understand the internal structure of charmed baryons.

Last week at the 16th International Conference on B-Physics at Frontier Machines, "Beauty 2016” , Marseille, France, the LHCb collaboration presented the updated result of a measurement of the semileptonic asymmetry, assl, related to a difference between a probability of a beauty meson, B0s, to oscillate into its antimatter partner, B0s, and a probability of the reverse process.
In this mass region many charm quark-antiquark (cc) states are also present bound by a strong force in an atom-like system called charmonium In addition the two different forms of exotic particles can be formed in this mass region: 1. About 10 fm large loosely bound DD molecules in which D and D mesons are bound by a strong force in analogy to the deuterium nucleus composed of a proton and a neutron, and 2. About 1 fm compact four quark qqqq elementary particles, tetraqarks.

The phenomenon was first observed in 1964 in the decay of neutral K mesons, and the two physicists who made the discovery, James Cronin and Val Fitch , were awarded the Nobel Prize in physics in 1980 Such a discovery came as a great surprise at the time, as it was firmly believed by the community of particle physicists that the CP symmetry could not be violated.
The increase of number of recorded charmed particles per unit of integrated luminosity was even higher, by a factor of 5, both due to the higher cross-section at 13 TeV and to improvements in the event selection (so-called trigger”) during data taking.
In a recent paper the authors claim that a global analysis of the LHCb data, together with previous measurements, show a deviation of 4.5σ with respect to Standard Model expectations, which can be explained with the same mechanism (reduced Wilson coefficient C9 for experts).

At the LHCC open session, the LHCb collaboration presented the first evidence for an exotic particle decaying into another charmonium (cc) meson, the ηc(1S), plus a π-. The ηc(1S) was reconstructed through its decay to a proton (p) and an antiproton (p).
For example, in B±→π±K+K- decays a broad feature at low K+K- invariant mass that was previously observed by the BaBar collaboration PRL 99 (2007) 221801 appears to be present only in B+ decays, as shown by the filled triangles distribution in the left figure above, and not in the B- distribution (open triangles).
Studies of RK could detect the existence of additional Higgs bosons, new scalar or new pseudo-scalar particles that violate lepton universality, or heavy Z ”, Z', which was suggested as a possible explanation of deviations observed in the P'5 distribution in the analysis of B0→K0μ+μ- decays, see 9 August 2013 news.

The ability of LHCb to perform measurements using different b-hadron species, notably including the Bc meson in this case, but also the Bs meson and the Λb baryon in the forthcoming future, will play a crucial role in order to clarify the global picture of deviations from lepton flavour universality that is emerging.
Last year at the Hadron Collider Particle Symposium in Kyoto, the Collaboration presented the first evidence, with 3.5σ significance, for the B0s→μμ decay using the total 1.0 fb-1 of data taken in 2011 and 1.1 fb-1 of the data accumulated in 2012, see 12 November 2012 news.

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