Unitary Models of Nuclear Resonance Reactions

Relativistic quantum field theory is extended so that it can be used as a basis for a qualitative study of nuclear resonance reactions. The general resonance formulae are derived in a relativistic form, and the interference between neighbouring levels is investigated. It is assumed that resonance arises from the formation of a compound nucleus which subsequently disintegrates. The essential features of resonance and level width are, in the first instance, derived from a simple resonating model. This shows that, while resonance arises directly from the Feynman propagator in lowest approximation, the level widths come from considering an infinite series of Feynman-Dyson diagrams; these can be represented by an integral equation. In considering a general nuclear resonance reaction it is necessary to use compound propagators, which were introduced by the author in the first paper of this series. The general form of the compound propagator is obtained in stable approximation, and the integral equation is derived which allows for the possibility of disintegration. The solution of this equation leads to the relativistic formulae for a general resonance reaction.

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Resolution of a Paradox in the Variational Formulation of Nuclear-Resonance Reactions

Physical Review C ◽

10.1103/physrevc.2.1167 ◽

1970 ◽

Vol 2 (3) ◽

pp. 1167-1168 ◽

Cited By ~ 9

Author(s):

R. A. Chatwin

Keyword(s):

Variational Formulation ◽

Nuclear Resonance ◽

Resonance Reactions

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Hydrogenated tantalum: A convenient calibration substance for hydrogen profile analysis using nuclear resonance reactions

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/0168-583x(89)90716-7 ◽

1989 ◽

Vol 42 (2) ◽

pp. 257-263 ◽

Cited By ~ 22

Author(s):

B. Hjörvarsson ◽

J. Rydén ◽

T. Ericsson ◽

E. Karlsson

Keyword(s):

Profile Analysis ◽

Nuclear Resonance ◽

Resonance Reactions

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Measurements of Energy Loss of Charded Particles Travelling in Crystalline Materials along the Channeling Directon

HNPS Proceedings ◽

10.12681/hnps.3361 ◽

2021 ◽

Vol 12 ◽

pp. 82

Author(s):

M. Kokkoris ◽

R. Vlastou ◽

C. T. Papadopoulos ◽

X. Aslanoglou ◽

S. Kossionides ◽

...

Keyword(s):

Energy Loss ◽

Computer Simulations ◽

Charged Particles ◽

Crystalline Material ◽

Nuclear Resonance ◽

Exponential Rate ◽

Crystalline Materials ◽

Resonance Reactions ◽

Light Charged Particles ◽

Good Agreement

A method for determining the energy loss and mean dechanneling distance of light charged particles traveling along a low index axis of a crystal in the backscattering geometry, is presented. The method is based on nuclear resonance reactions which act as a marker for the range in the backscattering spectra. Computer simulations based on the assumption of an exponential rate of dechanneling of the incoming particles in the crystalline material, are in good agreement with measured spectra. The results of applying this method to protons and alphas in crystals of Si, SiO2, SiC and MgO are discussed and possible improvements are indicated.

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Materials impurity analysis by means of nuclear resonance reactions

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/0168-583x(91)95034-b ◽

1991 ◽

Vol 56-57 ◽

pp. 809-811

Author(s):

R.S. Hornady

Keyword(s):

Nuclear Resonance ◽

Impurity Analysis ◽

Resonance Reactions

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Analysis of Nitrogen, Boron, and Hydrogen of i-BN Films Fabricated by the Ion Beam Assisted Deposition

MRS Proceedings ◽

10.1557/proc-128-85 ◽

1988 ◽

Vol 128 ◽

Cited By ~ 2

Author(s):

J-P. Hirvonen ◽

J. K. Hirvonen

Keyword(s):

Deposition Temperature ◽

Boron Concentration ◽

Ion Beam ◽

Nuclear Resonance ◽

Low Level ◽

Ion Beam Assisted Deposition ◽

Resonance Reactions ◽

Almost All ◽

Deposition Conditions

ABSTRACTThe concentrations of the main constituents of hard i-BN films produced by the ion beam assisted deposition were measured using the nuclear resonance reactions 11B(p,γ) 12C at Ep = 163 keV, and 15N(p,αγ) 12C at Ep = 429 key, respectively. The hydrogen contamination of the samples was investigated using the forward recoil spectroscopy (FRES) technique with a 2 MeV He+ beam. Some complementary analyses of carbon and oxygen were performed using (d,p) and (d,α) -reactions.Hyperstoichiometric boron concentration were found in almost all films. The relative concentrations of nitrogen and boron were also slightly dependent on the deposition conditions as well as the deposition temperature. Contrary to this, hydrogen contamination, that was generally at a low level with few exceptions, was more independent of these parameters.

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