Sökning: "γ rays"

Visar resultat 11 - 15 av 22 avhandlingar innehållade orden γ rays.

1. 11. Position-sensitive germanium detectors for gamma-ray tracking, imaging and polarimetry

   Författare :Anton Khaplanov; Bo Cederwall; Araceli Lopez-Martens; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; Kärnfysik;

   Sammanfattning : Modern germanium detectors are often manufactured with two-dimensionally segmented electrical contacts. Signals induced in each segment are read out simultaneously when a photon is detected. Detailed pulse shape analysis (PSA) of these signals allows to resolve positions of individual γ-ray interactions with a precision of at least a few mm. LÄS MER

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

   Författare :Karin Andgren; Bo Cederwall; Paul Nolan; KTH; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

4. 13. Collectivity in Neutron-Rich Erbium Isotopes

   Författare :Aila Gengelbach; Johan Nyberg; Lantz Mattias; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear structure; collective excitations; rare-earth nuclei; gamma-ray spectroscopy; AGATA; PRISMA; Physics with specialization in Nuclear Physics; Fysik med inriktning mot kärnfysik;

   Sammanfattning : Neutron-rich rare-earth nuclei around the maximum of collectivity are predicted to exist with an extremely stable intrinsic configuration in their ground-state structure. Due to the high degree of axial symmetry and large deformation, these nuclei are also excellent candidates for having long-lived high-K isomers. LÄS MER

5. 14. Performance Studies and Star Tracking for PoGOLite

   Författare :Cecilia Marini Bettolo; Mark Pearce; Nicolas Produit; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polarization; pulsars; x-ray; PoGOLite; Astroparticle physics; Astropartikelfysik;

   Sammanfattning : PoGOLite is a balloon-borne experiment, which will study polarized soft γ-ray emissionfrom astrophysical targets in the 25-80 keV energy range by applying well-typephoswich detector technology. Polarized γ-rays are expected from a wide variety of sources including rotation-powered pulsars, accreting black holes and neutron stars,and jet-dominated active galaxies. LÄS MER

7. 15. Collective Structure of Neutron-Rich Rare-Earth Nuclei and Development of Instrumentation for Gamma-Ray Spectroscopy

   Författare :Pär-Anders Söderström; Johan Nyberg; Ayşe Ataç; John Simpson; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nuclear structure; collective models; 150 < A < 189; AGATA; HPGe detectors; gamma-ray tracking; NEDA; pulse-shape discrimination; neutrons; neural network; Nuclear physics; Kärnfysik; Physics with specialization in Nuclear Physics; Fysik med inriktning mot kärnfysik;

   Sammanfattning : Neutron-rich rare-earth nuclei are among the most collective nuclei that can be found in nature. In particular, the doubly mid-shell nucleus 170Dy is expected to be the nucleus where the collective structure is maximized. LÄS MER