orthopositronium


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orthopositronium

[¦ȯr·thō‚päz·ə′trō·nē·əm]
(particle physics)
The state of positronium in which the positron and electron have parallel spins.
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In 1990, researchers at the University of Michigan in Ann Arbor measured the lifetime of orthopositronium and found that it was slightly shorter than predicted by theory.
He and his colleagues would confine orthopositronium to a sensitive heat-measuring device, called a calorimeter.
By the new QED effect and the reformulated BS equation, another new QED effect, a term in the orthopositronium decay rate that is missing in the conventional QED is discovered.
Then by this modified ground state of the positronium, we derive in Section 26 another new QED effect, a term missing in the theoretic orthopositronium decay rate of the conventional QED theory, and show that this new theoretical orthopositronium decay rate agrees with the experimental decay rate, completely resolving the orthopositronium life time puzzle [33-52].
2]) as they interact with positrons in the process of production of orthopositronium [o-Ps, [sup.
For an explanation and quantitative description of the orthopositronium anomalies [1-3] the hypothesis of representation of the [[beta].
It is now the 20th anniversary of the observation of anomalies of orthopositronium annihilation (both discovered in 1987) in experiments conducted by two groups of researchers: one group in the USA, headed by the late Prof.
Recently my long-time colleague, Boris Levin, one of the discoverers of the anomalies, suggested that the last experiment of the Michigan group, by which it has claimed resolution of one of the anomalies [1], was set up so that an electric field introduced into the experiment (it accelerates the particle beam before the target) mere suppressed the anomaly despite the electric field helps to reach complete thermalization of orthopositronium in the measurement cell.
The uniqueness of orthopositronium dynamics (virtual single-quantum (
2] are those of three-quantum annihilation of the orthopositronium component.
As known, Standard Model of Quantum Electrodynamics explains all known phenomena with high precision, aside for anomalies in orthopositronium annihilation, discovered in 1987.
Therefore today, in order to judge the alternative models as true or false, we should compare their predictions to orthopositronium annihilation anomalies, the solely unexplained by the Standard Model.