Search results for "Nuclear fission"

ARE AMORPHOUS ALLOYS SUITABLE AS A STORAGE MATRIX FOR FISSION PRODUCT KRYPTON ?

1980

Summation Calculations for Reactor Antineutrino Spectra, Decay Heat and Delayed Neutron Fractions Involving New TAGS Data and Evaluated Databases

2018

9 pags., 3 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0

Internal and External Conditions for the Discovery of Nuclear Fission by the Berlin Team

1983

My subject concerns the constellation of conditions which led to the discovery of nuclear fission by Otto Hahn, Lise Meitner, and Fritz Strassmann.1 It is on purpose that I mention all three names of the Berlin team and that I order them alphabetically, in spite of the fact that today Hahn is usually credited with the discovery of the fission of heavy nuclei. Stressing Hahn’s name, however, ignores the fact that Hahn himself called Fritz Strassmann a codiscoverer. It is absolutely wrong to attribute Hahn’s attitude to modesty and to regard that as the motive that caused him to let his young assistant share his fame. I am much more convinced that it was the cooperationof all three scientists…

The discovery of nuclear fission 50 years ago a few remarks

1990

Abstract  A historical account on the details of the discovery of nuclear fission in 1939 is given.

Fission product yields at intermediate energy

1998

The results of experimental and theoretical studies of fission product yields in proton-induced fission of 238U are presented. The yields of neutron-rich Ni, Cu, Zn, Ga and Ge—isotopes were measured by 25 MeV protons and the ion guide-based isotope separator technique. The pre-neutron emission fragment mass distributions were measured by protons at energies Ep=20, 35, 50 and 60 MeV using time-of-flight method. The results indicate enhancement for superasymmetric mass division at intermediate excitation energy of the fissioning nucleus. A model calculation of fission products yields for fission of 238U by protons and neutrons is presented which predicts the formation cross sections for neutr…

The on-line isotope separation facility helios at the mainz reactor

1980

Abstract The on-line isotope separation facility HELIOS consisting of a helium-jet transport system coupled to a high transmission mass separator is described. The main characteristics of the system were determined from γ-ray measurements on neutron-rich nuclides. The transmission from the target to the skimmer is about 60%; the overall efficiency for typical fission product elements is 0.05–0.2% and the transit time for Cs is about 1.0 s.

Superasymmetric fission at intermediate energy and production of neutron-rich nuclei with A < 80

1997

Abstract The yields of neutron-rich Ni, Cu, Zn, Ga and Ge-isotopes were measured in 25 MeV proton induced fission of 238 U using the ion guide-based isotope separator technique. The results indicate enhancement for superasymmetric mass division at intermediate excitation energy of the fissioning nucleus and show the potential of this reaction for the production of neutron-rich exotic nuclei around Z = 28.

Half-lives andP n values of delayed-neutron precursors in the mass chains 85?87, 92, 135, 136 and 145

1978

Further results are presented on half-lives and neutron emission probabilities (P n ) of short-lived delayed-neutron precursors in the mass chains 85–87, 92, 135, 136 and 145 obtained with the recoil focussing parabola-type mass separator for unslowed fission products LOHENGRIN installed at the Grenoble high-flux reactor. A newP n -value of (44±14)% is given for the (0.73±0.06)s87As; theP n -values of seven precursor nuclides have been redetermined: (1.9±0.1)s85As with (22±8)%, 0.9s86As with (10.5±2.2)%, (0.35±0.04)s92Br with (21±8)%, (1.6±0.15)s135Sb with (14±1)%, (0.9±0.1)s136Sb with (19±9)%, (17.5±0.2)s136Te with (2.0±1.0)% and 0.6s145Cs with (12.5±3.0)%. The results are compared with th…

Impact of TAGS Measurement on FP Decay Data and Decay Heat Calculations

2011

Discovery of New Fission Product Activities in the A=110–118 Mass Region

1986

Neutron rich nuclei around the mass A=100 have recently attracted both theoretical and experimental interest since they are expected to form a new region of strong deformation. In contrary, very little experimental information is available in the adjacent transitional region A= 110–118. Due to expected isomerism in this region both low and high spin states can be studied via beta decay in many nuclei. The studies of these nuclides have many experimental difficulties. They are only weakly produced in thermal neutron induced fission and because all the elements in this mass region (Tc, Ru, Rh, Pd) have very high melting points they have not been available as beams of on-line isotope separator…