Search for dissertations about: "gamma-ray technique"

Showing result 1 - 5 of 12 swedish dissertations containing the words gamma-ray technique.

2. 1. Characterisation of the Neutron Wall and of Neutron Interactions in Germanium-Detector Systems

   Author : Joa Ljungvall; Johan Nyberg; Andres Gadea; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; High-purity Ge detectors; Liquid scintillator detectors; Neutron scattering; Digital electronics; Time-of-flight technique; Pulse-shape simulation and analysis; Monte Carlo simulations; Geant4; Gamma-ray tracking; AGATA; Neutron Wall; Kärnfysik; Nuclear physics; Kärnfysik;

   Abstract : A Monte Carlo simulation of the Neutron Wall detector system has been performed using Geant4, in order to define optimum conditions for the detection and identification of multiple neutrons. Emphasis was put on studying the scattering of neutrons between different detectors, which is the main source of the apparent increase of the number of detected neutrons. READ MORE

4. 2. Applications of Gamma Ray Spectroscopy of Spent Nuclear Fuel for Safeguards and Encapsulation

   Author : Christofer Willman; Ane Håkansson; Henrik Nylén; Uppsala universitet; []
   Keywords : Nuclear physics; gamma radiation; spectroscopy; spent nuclear fuel; safeguards; HRGS; MOX; Kärnfysik;

   Abstract : Nuclear energy is currently one of the world’s main sources of electricity. Closely connected to the use of nuclear energy are important issues such as the nonproliferation of fissile material that may potentially used in nuclear weapons (safeguards), and the management of the highly radioactive nuclear waste. READ MORE

5. 3. Collective Excitations in Transitional Nuclei Studied by Means of gamma-ray Spectroscopy and Lifetime Measurements

   Author : Hongjie Li; Bo Cederwall; Radomira Lozeva; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : Despite that it is more than 100 years since the atomic nucleus was first dis- covered by Ernest Rutherford and coworkers, many of its features still elude our understanding. The fact that the fundamental interactions between the nuclear constituents; nucleons, and ultimately quarks, are not yet known in detail, and the complexity of the nuclear many-body system compound the great challenges facing theoretical interpretations of experimental data. READ MORE

6. 4. Studies of collective phenomena in neutron deficient nuclei : by means of lifetime measurements, angular correlation measurements and the recoil-decay tagging technique

   Author : Karin Andgren; Bo Cederwall; Paul Nolan; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; heavy-ion reactions; multi-detector arrays; recoil separator; in-beam gamma-ray spectroscopy; high spin states; lifetime measurements; recoil-decay tagging; nuclear shape; Nuclear physics; Kärnfysik;

   Abstract : The nucleus is a mesoscopic system that retains features from both the quantum and macroscopic worlds. A basic property of a macroscopic body is its shape. Nuclear shapes can be deduced from experimental data as they influence the excitation mode of the nucleus and hence the energies and lifetimes of its excited levels. READ MORE

7. 5. A Tomographic Measurement Technique for Irradiated Nuclear Fuel Assemblies

   Author : Staffan Jacobsson Svärd; Anders Bäcklin; Ane Håkansson; Klaas van der Meer; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; tomography; nuclear fuel; SPECT; core physics; validation; pin power; safeguards; partial-defect verification; Kärnfysik; Nuclear physics; Kärnfysik;

   Abstract : The fuel assemblies used at the Swedish nuclear power plants contain typically between 100 and 300 fuel rods. An experimental technique has been demanded for determining the relative activities of specific isotopes in individual fuel rods without dismantling the assemblies. READ MORE