Sökning: "spontaneous decay"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden spontaneous decay.

  1. 1. Spectroscopy along Decay Chains of Element 114, Flerovium

    Författare :Anton Såmark-Roth; Kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Superheavy elements; Flerovium; Nuclear Structure; Spectroscopy; Alpha decay; Electromagnetic decay; Spontaneous fission; Germanium detectors; Fysicumarkivet A:2021:Såmark-Roth;

    Sammanfattning : This thesis focusses on a nuclear spectroscopy experiment conducted to study α-decay chains stemming from isotopes of flerovium (element Z = 114). An upgraded TASISpec decay station was placed behind the gas-filled separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. LÄS MER

  2. 2. DESIREE: Instrumentation Developments and Hot Metal Cluster Decays

    Författare :Emma K. Anderson; Henning Schmidt; Henrik Cederquist; Henning Zettergren; Oded Heber; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; DESIREE; microchannel plate; clusters; spontaneous decay; small metal cluster anions; silver; copper; gold; carbon dianions; fragmentation; vibrational autodetachment; DESIREE; mikrokanalplattor; kluster; spontana sönderfall; små metallklusteranjoner; silver; koppar; guld; kol di-anjoner; fragmentering; Physics; fysik;

    Sammanfattning : This thesis presents instrumentation developments and measurements performed at the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. DESIREE operates at cryogenic temperatures ~13 K, with very low background pressures of ~10-14mbar, allowing the observation of stored ions to long times of tens of seconds and longer. LÄS MER

  3. 3. Element 115

    Författare :Ulrika Forsberg; Kärnfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; superheavy elements; element 115; new elements; alpha decay; X rays; gamma rays; nuclear structure; spontaneous fission; Fysicumarkivet A:2016:Forsberg; kärnstruktur; supertunga grundämnen; nya grundämnen; alfasönderfall; röntgenstrålning; gammastrålning; spontan fission; element 115; spektroskopi;

    Sammanfattning : This thesis is devoted to detailed studies of element 115 decay chains using the highly efficient multi-coincidence alpha, electron, gamma and X-ray detector setup TASISpec at the gas-filled separator TASCA at GSI, Darmstadt, Germany. In a three-week long experiment thirty new decay chains assumed to stem from element 115 isotopes were observed together with the very first detections of gamma rays and potential X-rays from these nuclei. LÄS MER

  4. 4. The Curious Case of Hot Metal Clusters : Spontaneous decay of excited, small silver and copper cluster anions in DESIREE

    Författare :Emma Anderson; Henning Schmidt; Daniel Harding; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; fysik;

    Sammanfattning : Clusters anions are complex systems which, when formed with high internal energies, can decay via fragmentation and/or electron loss and may also cool via photon emission (radiative cooling). By studying the spontaneous decay mechanisms of small metal clusters, we can gain insight into the structure and properties of these systems. LÄS MER

  5. 5. Thermal Properties of Clusters and Molecules - Experiments on Evaporation, Thermionic Emission, and Radiative Cooling

    Författare :Erika Sundén; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; water clusters fullerenes unimolecular decay evaporation thermionic emission radiative decay cooling rates heat capacities;

    Sammanfattning : This thesis presents experiments performed on clusters and molecules, where the three channels of unimolecular decay have been studied. Evaporation from protonated and negatively charged water cluster have yielded size dependent heat capacities, where the smallest sizes with fewer than $21$ molecules show a heat capacity similar to bulk ice whereas clusters with molecules between $21$ and $300$ have a heat capacity in between that of ice and liquid water. LÄS MER