|Author||Agodi, A. ♦ Eberle, E.|
|Source||United States Department of Energy Office of Scientific and Technical Information|
|Subject Keyword||CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS ♦ BREIT-WIGNER FORMULA ♦ CONFIGURATION ♦ CROSS SECTIONS ♦ DIFFERENTIAL EQUATIONS ♦ DISPERSIONS ♦ ENERGY LEVELS ♦ FIELD THEORY ♦ HAMILTONIAN ♦ INTERACTIONS ♦ MATHEMATICS ♦ MATRICES ♦ NUCLEAR MODELS ♦ NUCLEAR REACTIONS ♦ NUCLEAR THEORY ♦ NUCLEI ♦ NUCLEONS ♦ OPTICAL MODEL ♦ RESONANCE ♦ SCATTERING ♦ SURFACES|
|Abstract||A new dispersion theory of nuclear reactions is presented which is a generalization of the existing ones. The theory is centered around the possibility of defining a class of problems equivalent to the original scattering problem in the sense that their solutions all determine the same transition matrix elements. These equivalent problems are generated by suitably projecting the original one on a subspace of the linear space spanned by the continuum eigenstates of the total hamiltonian, containing the initial and final channel states. A derivation of the Breit-Wigner formula analogous to Feshbach's can be given in the theory, independently of any configuration space representation. The direct processes are then defined by performing the energy average on the transition matrix elements, so that the contributions from the long- lived''compound'' states are lost. In the case of nucleon-nucleus scattering, this is shown to give an alternative definition of the optical model quite analogous to the conventional ones though perhaps more accessible to a field theoretical analysis. Moreover it is shown that the well-known surface contributions to direct reactions can be isolated quite naturally in the formalism from the other direct contributions.|
|Learning Resource Type||Article|
|Publisher Department||Universita, Catania, Italy ♦ Centro Siciliano di Fisica Nucleare, Catania, Italy|
|Organization||Universita, Catania, Italy ♦ Centro Siciliano di Fisica Nucleare, Catania, Italy|
Ministry of Human Resource Development (MHRD) under its National Mission on Education through Information and Communication Technology (NMEICT) has initiated the National Digital Library of India (NDLI) project to develop a framework of virtual repository of learning resources with a single-window search facility. Filtered and federated searching is employed to facilitate focused searching so that learners can find out the right resource with least effort and in minimum time. NDLI is designed to hold content of any language and provides interface support for leading vernacular languages, (currently Hindi, Bengali and several other languages are available). It is designed to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is being developed to help students to prepare for entrance and competitive examinations, to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is being developed at Indian Institute of Technology Kharagpur.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Human Resource Development (MHRD), through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
For any issue or feedback, please write to email@example.com