Author: Paul KrugerPublisher:
ISBN:
Category :
Languages : en
Pages : 182
Book Description
High Energy Fission of Heavy Elements
Author: Paul KrugerStudies of Fission in Heavy Elements Under High-energy Bombardments
Author: Herbert Max SteinerPublisher:
ISBN:
Category : Fission products
Languages : en
Pages : 186
Book Description
The Nuclear Properties of the Heavy Elements: Fission phenomena
Author: Earl K. HydePublisher:
ISBN:
Category : Heavy elements
Languages : en
Pages : 588
Book Description
High Energy Nuclear Reactions
Author: I. PerlmanPublisher:
ISBN:
Category : Cyclotrons
Languages : en
Pages : 14
Book Description
Heavy Elements And Related New Phenomena (In 2 Volumes)
Author: Walter GreinerPublisher: World Scientific
ISBN: 9814525308
Category : Science
Languages : en
Pages : 1171
Book Description
This book reviews recent developments in the field of superheavy elements and the related phenomena of fission, cluster radioactivity, and drip line physics. Both the experimental and theoretical aspects are dealt with in detail. For the production of new elements in the laboratory, the process of cold compound nucleus formation is found to be most favorable both theoretically and experimentally. However, experimentally, hot fusion of nuclei has also been used. Both the physical and chemical methods of synthesizing new elements are discussed. The theoretical approaches considered here are those of the quantum-mechanical fragmentation theory, the self-consistent Hartree-Fock theory, and the relativistic mean field theory. Fission, a process inverse to the fusion of two nuclei, is also observed to be most favourably a cold phenomenon. Other important results are bi-modal fission and high n-multiplicity fission, which leads to the hyperdeformed scission mode. Cluster radioactivity is discussed both as a heavy cluster emission process and as super-asymmetric fission. The theory as well as the present experimental status are reviewed. Physics at drip lines is interesting not only for their structural properties but also for their use in the fusion of two nuclei; both aspects are discussed.
Relative High Energy Neutron Yields from Targets Bombarded with Protons and Deuterons (UCRL-440)
Author: William J. KnoxPublisher:
ISBN:
Category : Bismuth
Languages : en
Pages : 30
Book Description
Relative neutron yields in the forward direction from various target elements bombarded with 350 Mev protons and 190 Mev deuterons have been measured. Bismuth fission chambers with a threshold of about 50 Mev were used to detect the high energy neutrons. The actual flux of protons or deuterons traversing each target was determined from the activities induced in graphite monitors attached to the target. When a deuteron beam is used, the neutron yields for light elements agree with the values predicted by the deuteron stripping theory. For the heavy elements the observed values are fitted best by adding a function proportional to Z-sq to the stripping theory values. This may be interpreted as evidence for the production of high energy neutrons by the electric field disintegration of the deuteron. The neutron yields from the proton beam vary approximately as (A - Z)(exp(2/3)) for target elements from C to U. This indicates that the heavy elements are not completely transparent to 350 Mev protons. Beryllium has an anomalous neutron yield 50% higher than that for C. Calculations and measurements on the problem of multiple traversals of beam particles through thin targets are presented.
Spontaneous Fission of the Heaviest Elements
Author: Sven A. E. JohanssonPublisher:
ISBN:
Category : Nuclear fission
Languages : en
Pages : 30
Book Description
Cosmic Rays at Earth
Author: P.K.F. GriederPublisher: Elsevier
ISBN: 0080530052
Category : Science
Languages : en
Pages : 1117
Book Description
In 1912 Victor Franz Hess made the revolutionary discovery that ionizing radiation is incident upon the Earth from outer space. He showed with ground-based and balloon-borne detectors that the intensity of the radiation did not change significantly between day and night. Consequently, the sun could not be regarded as the sources of this radiation and the question of its origin remained unanswered. Today, almost one hundred years later the question of the origin of the cosmic radiation still remains a mystery.Hess' discovery has given an enormous impetus to large areas of science, in particular to physics, and has played a major role in the formation of our current understanding of universal evolution. For example, the development of new fields of research such as elementary particle physics, modern astrophysics and cosmology are direct consequences of this discovery. Over the years the field of cosmic ray research has evolved in various directions: Firstly, the field of particle physics that was initiated by the discovery of many so-called elementary particles in the cosmic radiation. There is a strong trend from the accelerator physics community to reenter the field of cosmic ray physics, now under the name of astroparticle physics. Secondly, an important branch of cosmic ray physics that has rapidly evolved in conjunction with space exploration concerns the low energy portion of the cosmic ray spectrum. Thirdly, the branch of research that is concerned with the origin, acceleration and propagation of the cosmic radiation represents a great challenge for astrophysics, astronomy and cosmology. Presently very popular fields of research have rapidly evolved, such as high-energy gamma ray and neutrino astronomy. In addition, high-energy neutrino astronomy may soon initiate as a likely spin-off neutrino tomography of the Earth and thus open a unique new branch of geophysical research of the interior of the Earth. Finally, of considerable interest are the biological and medical aspects of the cosmic radiation because of it ionizing character and the inevitable irradiation to which we are exposed. This book is a reference manual for researchers and students of cosmic ray physics and associated fields and phenomena. It is not intended to be a tutorial. However, the book contains an adequate amount of background materials that its content should be useful to a broad community of scientists and professionals. The present book contains chiefly a data collection in compact form that covers the cosmic radiation in the vicinity of the Earth, in the Earth's atmosphere, at sea level and underground. Included are predominantly experimental but also theoretical data. In addition the book contains related data, definitions and important relations. The aim of this book is to offer the reader in a single volume a readily available comprehensive set of data that will save him the need of frequent time consuming literature searches.
Radiation Chemistry and Nuclear Energy
Author: Milton BurtonPublisher:
ISBN:
Category : Nuclear energy
Languages : en
Pages : 20
Book Description
On the Photofission Cross Sections Near Threshold of Nuclei in the Region of the Very Heavy Elements
Author: Kenneth M. ClarkePublisher:
ISBN:
Category : Nuclear fission
Languages : en
Pages : 98
Book Description
Variations in the photofission cross section near ''threshold'' with initial kind of nucleus were investigated for seven spheroidal nuclei in the region of atomic numbers 90, 92, 93. The photofission cross sections at the two discrete energies 6.14 and 7.0 Mev were determined for the following even-even nuclides: Th-232, U-234, U-236, and U-238; and also the odd-A nuclides. U-233, U-235 and Np-237. This problem was suggested partly by the qualitative proposals of A. Bohr concerning odd-parity states and low energy photofission and partly by the results of betatron studies at low energies on the very heavy elements.