Muonium atom

Muonium, atom number zero , is composed of a positron and an electron. Calculate foe Rydberg constant for this species. 

Calculations have been extended to muonium bonding. For BrXBr and IXI, where X can be H, D or a muonium atom (which has a mass of 0.114 au and a lifetime of 2.2 x 10 s) the order of bond energies is BrDBr < BrHBr < BrMuBr (Clary and Connor, 1984). 

Kinetic data for the reactions of diazodiphenylmethane in 10 different alcohols with 2-(4-phenyl substituted)cyclohex-l-enylcarboxylic acids (75) were correlated using the extended Hammett equation.68 Reaction of the species (76)-(78) with the light radioactive H isotope, the muonium atom, has been studied.69 The largest primary kinetic isotope effects ever reported (ca 850) are seen in this work for the addition of muonium to one of the C=0 groups. 

Prom electron-positron scattering at the highest achievable energies we can infer that leptons have dimensions of less than 10-18m [1]. These particles may therefore be regarded as point-like objects. The muonium atom (M=/j,+e ) is the hydrogen-like bound state of leptons from two different particle generations, an antimuon(p+) and an electron (e ) [2,3],... 

The dominant interaction within the muonium atom is electromagnetic. This can be treated most accurately within the framework of bound state Quantum Electrodynamics (QED). There are also contributions from weak interaction which arise from Z°-boson exchange and from strong interaction due to vacuum polarization loops with hadronic content. Standard theory, which encompasses all these forces, allows to calculate the level energies of muonium to the required level of accuracy for all modern precision experiments1. 

The most efficient mechanism to obtain M is e capture after stopping p+ in a suitable noble gas. This technique was employed already in the discovery experiment of the muonium atom through its characteristic muon spin rotation in a magnetic field by V.W. Hughes and collaborators in 1960. There the atoms were formed in Ar gas [8], where efficiencies of 65(5)% are possible. In the most recent precision measurements of Avhfs and the muon magnetic moment... 

Fig. 4. The fine structure constant a has been determined with various methods [25-28]. most precise is the determination from the magnetic anomaly of the electron. The muonium atom offers two different routes which uses independent sets of fundamental constants. The disagreement (the error bars are mostly statistical) seem to indicate that the value h/me from neutron de Broglie wavelength measurements may be quoted with too high accuracy...

The relevant measurements were performed during in total 6 month distributed over 4 years during which 5.7 1010 muonium atoms were in the interaction region. Out of those, one event fell within a 99% confidence interval of all relevant distributions (Fig. 12). The expected background due to accidental coincidences was 1.7(2) events. Thus an upper limit on the conversion probability of... 

It is the interplay between particle physics and QED phenomena in the muonium atom which cause increasing understanding of fundamental forces and increasing reliability of extracted fundamental constants. None of both sides could reach significant results without the other. With the significant improvement expected for muon beam rates at various places we can look forward to further insights and maybe hints why there are particle generations. 

The simulation of hydrogen by muons has proved to be extremely valuable in the identification of potential sites for hydrogen in semiconductors and insulators. Although the muon has a mass one-ninth that of the proton, its interaction with the host lattice, both electronically and chemically, is virtually identical to that of a proton. During its 2.2 microsecond lifetime (experiments are frequently undertaken over a timescale of up to ten lifetimes), the muon can diffuse, interact with, and adopt positions in the lattice that protons themselves would occupy. If the temperature is sufficiently low, muons can capture electrons to form muonium atoms. The reduced mass of muonium is within 0.5% of that of... 

Muonium atoms ( " e ) are formed by absorption of positively charged muons in matter. They show similarities to positronium atoms. 

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