Exotic hydrogen atoms

T.S. Jensen, V.E. Markushin, CoUisional deexcitation of exotic hydrogen atoms in highly excited states. 11. Cascade calculations, Eur. Phys. J. D 21 (2002) 271-283. 

Properties of exotic hydrogen atoms (Horvath and Lambrecht 1984)... 

The exotic hydrogen atoms, systems consisting of a proton and a negative particle, or a positive particle and an electron, are special in many aspects (Eides et al. 2001). Their basic properties are summarized in O Table 28.2. 

As mentioned before, the neutral exotic hydrogen atom (having neither Coulomb nor Pauli repulsion) can penetrate other atoms and lose its exotic particle to a heavier nucleus. As the rate of this reaction is proportional to the number of collisions, it can be detected for hadronic atoms but it is really dramatic for muonic hydrogen as its lifetime is many orders of magnitude longer in the muon-catalyzed fusion measurements, for example, the concentration of heavy impurities has to be below 10 to avoid the distortion of the results by transfer. This feature was used to study muon capture in rare gas isotopes as it is sufficient to have less than 1% krypton in hydrogen to have all muons ended up in muonic krypton states. 

The new proposed deuteron model is founded on the principles of SLRT and QMT. In Ref. 4, where QMT is presented, it is shown that, if the electron in the hydrogen atom is excited to the state of the potential quantum number, n = 794 then, the electron turns into a positron. The consequence is very unusual the hydrogen atom turns into a system of one proton and one positron, which is undoubtedly a very odd example of CP violation. This has been obtained as a result of theoretical analysis based on the QMT principles. If this is experimentally proved, then atoms with very unusual physical characteristics will certainly be obtained, and a rather exotic regime of matter could be expected. 

The list of simple atoms accessible now includes a broad range of very different natural and artificial systems hydrogen, helium, muonium, positronium, various few-electron ions, muonic atoms and exotic atomic systems containing a pion, antiproton etc. While hydrogen atoms form the essential part of our universe, the unstable atoms like muonium do not exist in nature at all. The investigation of simple atoms has provided us with important knowledge on fundamental interactions between the particles these atoms consist of. 

Exotic Hydrogen-like Atoms From Theory to Technology... 

Exotic ground-state hydrogen atom Antiprotonic Helium is an exotic... 

The number N of vertices in the hydrogen-suppressed graph, the zeroth-order connectivity indices and °%v, and the first-order connectivity indices l% and 1xv, are listed in Table 2.2 for a diverse set of 357 polymers. All of the common polymers are included in this table. Many specialized and/or exotic polymers are also included. The polymers are listed in the order of increasing N. The easiest way to look up the connectivity indices of a polymer in Table 2.2 is to draw the stmcture of the repeat unit of the polymer, count the number of non-hydrogen atoms in this repeat unit, and search among the polymers with that value of N. For example, poly(vinyl fluoride), which is shown in Figure 2.3, has N=3. Its connectivity indices can be... 

Unless the metal is introduced as such, e.g. as a colloid or by metal-atom-vapour deposition (see later), the final and critical step is inevitably a reduction, performed either ex situ or in situ (or both). Molecular hydrogen is most often used, although carbon monoxide has a thermodynamic advantage, which is useful for less easily reducible species because the carbon dioxide produced is less effective than water in reversing the process. Reduction of a base metal oxide can be effected by hydrogen atoms spilling over (see Section 3.34) from reduced noble metal particles." More exotic reductants (e.g. Cr ions," oxirane" and... 

Some of you may think that these ionic species are unstable and are very rare exotic species in the nature. They are rare in the terrestrial atmosphere. However our terrestrial atmosphere is an exception in nature. The universe as a whole is much more highly ionized atomic and molecular ions are abundant and play important roles in various aspects of astrophysics. For example, since the work of Bethe and Hylleraas, stability of the hydrogen atom anion H is well-known. The H ions exist abundantly around the sun and its absorption of the solar radiation is the major cause for the sun s opacity as initially noted by Wildt and shown conclusively by a series of papers by Chandrasekhar and his colleagues.9... 

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