Double Charge Exchange Scattering of Low Energy Pions by Nuclei
Author : Daniel S. Koltun
Publisher :
Page : 22 pages
File Size : 12,16 MB
Release : 1965
Category : Pion double charge exchange
ISBN :
Author : Daniel S. Koltun
Publisher :
Page : 22 pages
File Size : 12,16 MB
Release : 1965
Category : Pion double charge exchange
ISBN :
Author :
Publisher :
Page : pages
File Size : 29,20 MB
Release : 1989
Category :
ISBN :
Recent measurements of pion double-charge exchange (DCX) at energies 20 to 70 MeV are providing a new means for studying nucleon-nucleon correlations in nuclei. At these energies the nucleus is relatively transparent, allowing simpler theoretical models to be used in interpreting the data and leading to a clearer picture. Also the contribution to DCX of sequential charge-exchange scattering through the intermediate analog state is suppressed near 50 MeV and transitions through non-analog intermediate states become very important. Recent theoretical studies by several groups have shown that while transitions through the analog route involve relatively long nucleon-nucleon distances, those through non-analog intermediate states obtain nearly half their strength from nucleon pairs with less than 1 fermi separation. Thus DCX near 50 MeV is an excellent way to study short-range nucleon-nucleon correlations. 31 refs., 29 figs., 4 tabs.
Author :
Publisher :
Page : 15 pages
File Size : 14,11 MB
Release : 1990
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Data are presented on pion-nucleus double-charge-exchange scattering at energies between 300 and 500 MeV, the highest energies measured so far, together with a review of results at lower energies. The small-angle excitation functions disagree with predictions based on a six-quark cluster model and on an optical model consistent with single-charge-exchange scattering at these energies, but they are consistent with a distorted-wave calculation. Data on f--2-shell nuclei are in partial agreement with a two-amplitude model which is successful at lower energies. In order to achieve good understanding of this process at these energies, more work, both experimental and theoretical, is needed. 16 refs., 6 figs.
Author : William R Gibbs
Publisher : World Scientific
Page : 622 pages
File Size : 26,1 MB
Release : 1990-09-24
Category :
ISBN : 9814611875
What do you associate with chemistry? Explosions, innovative materials, plastics, pollution? The public's confused and contradictory conception of chemistry as basic science, industrial producer and polluter contributes to what we present in this book as chemistry's image as an impure science. Historically, chemistry has always been viewed as impure both in terms of its academic status and its role in transforming modern society. While exploring the history of this science we argue for a characteristic philosophical approach that distinguishes chemistry from physics. This reflection leads us to a philosophical stance that we characterise as operational realism. In this new expanded edition we delve deeper into the questions of properties and potentials that are so important for this philosophy that is based on the manipulation of matter rather than the construction of theories./a
Author :
Publisher :
Page : 20 pages
File Size : 18,87 MB
Release : 1991
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A review is given of pion single- and double-charge exchange reactions at incident energies of 25 to 65 MeV leading to isobaric analog states, and in the case of double-charge exchange leading to the ground state of the residual nucleus. The crucial role of the higher nuclear transparency at low pion energies for the analysis of the data in terms of single and double scattering is demonstrated. The large effects on double-charge exchange produced by the spatial correlations in nuclear wave functions are evident. The data on 1f--2 nuclei at 35 MeV are used to establish the general validity of a shell-model-based two-amplitude model for these transitions. Recent measurements of the energy dependence between 25 and 65 MeV of double-charge exchange cross sections at forward angles are presented and discussed. 33 refs., 19 figs.
Author : M J Vicente-vacas
Publisher : World Scientific
Page : 730 pages
File Size : 39,79 MB
Release : 1992-03-27
Category :
ISBN : 9814555916
The proceedings reflect the recent experimental and theoretical progress in pion nuclear physics in topics like pionic atoms, pion absorption, charge exchange, (π, 2π), and others involving pions in nuclei using different probes, as electron photons or heavy ions. Related topics on chiral symmetry, low energy πN and (γ, π⁰) and quark degrees of freedom are also addressed.
Author : William R. Gibbs
Publisher :
Page : 626 pages
File Size : 38,39 MB
Release : 1990
Category : Nuclear structure
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Author : Arlene Paige Maclin
Publisher :
Page : 100 pages
File Size : 34,45 MB
Release : 1971
Category : Nuclear structure
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Author :
Publisher :
Page : 612 pages
File Size : 23,60 MB
Release : 1976
Category : Nuclear energy
ISBN :
Author : Lowell Arthur Charlton
Publisher :
Page : 20 pages
File Size : 20,66 MB
Release : 1968
Category :
ISBN :