The Quantal Theory of Immunity

10.1142/7269 ◽  
2010 ◽  
Author(s):  
Kendall A Smith
Keyword(s):  
Quantal Theory

A comparison of theory and experiment for photo-ionization cross-sections I. Neon and the elements from boron to neon

1951 ◽  
Vol 208 (1094) ◽  
pp. 408-418 ◽  
Keyword(s):  
Cross Sections ◽  
General Trend ◽  
Wave Functions ◽  
Ionization Cross ◽  
Hartree Fock ◽  
Quantal Theory ◽  
Ionization Cross Sections ◽  
Photo Ionization ◽  
Near Future ◽  
Dipole Length

The quantal theory of the continuous photo-electric absorption of radiation is briefly summarized, pàrticular attention being given to the alternative formulae available and to the accuracy to be expected in practical calculations. Detailed calculations are described for the photo-ionization cross-section of neon, a system for which it is understood that experimental data should be available in the near future. The calculation is made using Hartree-Fock wave functions and the two formulae of the dipole length and the dipole velocity. The corresponding cross-sections are found to be 5.8 and 4.4 x 10- 18 cm 2 . at the spectral head and to rise slowly with increasing frequency until a broad maximum is reached for an energy of the ejected electron of about 11 eV. A comparison is made with previous calculations on the elements from boron to neon ; the general trend of the results is discussed and improved estimates for boron and fluorine are given (10 x 10 -18 cm 2 . for boron and 4.3 x 10- 18 cm 2 . for fluorine at the spectral head).

scholarly journals The quantal theory of immunity

Cell Research ◽  
2006 ◽  
Vol 16 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Kendall A Smith
Keyword(s):  
Quantal Theory

Quantal theory of Coulomb absorption in heavy-ion scattering

1982 ◽  
Vol 138 (2) ◽  
pp. 215-236 ◽  
Author(s):  
B.V Carlson ◽  
M.S Hussein ◽  
A.J Baltz
Keyword(s):  
Heavy Ion ◽  
Ion Scattering ◽  
Quantal Theory ◽  
Heavy Ion Scattering

scholarly journals The formation of negative ions by positive-ion impact on surfaces

1938 ◽  
Vol 168 (933) ◽  
pp. 284-301 ◽  
Keyword(s):  
Ionization Chamber ◽  
Metal Surfaces ◽  
Negative Ions ◽  
Negative Ion ◽  
Distribution Analysis ◽  
Positive Ions ◽  
Mass Spectrograph ◽  
Quantal Theory ◽  
Double Mass ◽  
Positive Ion

The quantal theory of negative ions has now been developed considerably (Massey and Smith 1936; Massey 1938), but on account of difficulties of computing it is usually necessary to assume rather than to prove that a given ion exists, and then to discuss the probability of its formation by different processes. The work described here is a contribution to the experimental side of this subject. It had its origin in a projected attempt to measure the capture cross-section of mercury atoms for electrons, as a verification of Massey and Smith's (1936) then unpublished theory of this process. In considering this it became clear that the experiment would be one of unusual difficulty. Before proceeding with it, therefore, it was decided to verify the existence of Hg - as a stable entity, which is assumed in the quantal theory. this was in doubt since Stille (1933), in some careful experiments, had recently failed to obtain it from the plasma of various forms of discharge through mercury vapour, although it is known that negative ions tend to accumulate in such regions (Emeleus and Sayers 1938). Whilst one of us was repeating his experiments, with modifications which led to essentially the same results and will be describes elsewhere, Arnot and Milligan (1936 b ) reported that they had obtained Hg - by bombardment of metal surfaces with Hg + . A comparison of their work with our own showed only one essential point of difference, namely that the construction of their apparatus did not permit of degassing in situ , a condition satisfied with our tubes. Both for this reason and because of the intrinsic importance of their discovery it was thought desirable to repeat part of their work, with apparatus geometrically similar in electrode construction, but capable of being degassed in a furnace under vacuum. We were again unable to obtain Hg - after the apparatus had been degassed and in operation for a short of that of Hg - was obtained. There were, however, always present several light negative ions, which had the excess energies found by Arnot and Milligan (1936 b ) with Hg - . The conditions under which these were formed led us to suppose that they were produced by bombardment of the metal surfaces by mercury positive ions (Press 1937; Sloane 1937) and not capture of electrons by positive ions of the same species, the process suggested by Arnot and Milligan (1936 b ). The existence of a process of this type, which may be conveniently termed "sputtering" (Sloane and Press 1938), is also implied by some earlier work by J. S. Thompson (1931) which has, so far as we know, never been published in detail. It is, however, impossible to decide definitely ion (e. g. CO - ) when it hits the surface, so long as one is producing the negative ions on a metal surface in a plasma or ionization chamber. One cannot overlook the possibility of the negative ion being formed from its own positive ion, since the latter may be present in the plasma or ionization chamber, and CO + , for example, was in fact shown in our work to be there from the positive-ion mass spectra, although in quantity only a fraction of 1% of Hg + . An unambiguous decision on this point can only be reached by first isolating a particular positive ion by a mass spectrograph, then bombarding a surface by this in a high vacuum , and finally making a mass spectrographic and energy distribution analysis of the resultant negative ions. We have built a double mass spectrograph for this purpose and find that negative ions of one kind possessing energies in excess of that imparted to them by the accelerating fields can be produced by bombardment with positive ions of another kind (Sloane and Press 1938). An account of the experiments with the single mass spectrograph is given in 1. the experiments with the double mass spectrograph are described in 2.

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