Sahin, Elif (2023)
Lifetime measurement of the yrast 2⁺ state of ¹⁹⁰W.
Technische Universität Darmstadt
doi: 10.26083/tuprints-00024403
Dissertation, Erstveröffentlichung, Verlagsversion
Kurzbeschreibung (Abstract)
Over the past decades, studies of nuclear structure have led to numerous experiments aimed at understanding the properties of the nucleus. One of the main challenges of this field is the investigation of exotic nuclei, which are characterized by a large excess of neutrons or protons, and are located far from the stability line. To carry out this investigation, experimental techniques capable of producing and detecting these exotic nuclei are required. At the GSI Helmholtzzentrum für Schwerionenforschung in Germany, the DESPEC setup has been utilized to conduct important nuclear structure studies on exotic nuclei. This setup, in combination with the high-intensity primary beams available at GSI, has provided significant opportunities for the investigation of these exotic nuclei. In March 2021, an experiment was conducted at GSI where isotopes of interest were generated through the fragmentation of a primary ²⁰⁸Pb beam with an energy of 1 GeV/u directed at a ⁹Be target. The final products were then identified on an event-by-event basis in the FRS based on their proton number (Z) and mass-to-charge ratio (A/Q), and they were implanted in the DESPEC setup. To further investigate the nuclear structure of these exotic nuclei, measuring the lifetime of excited nuclear states was performed. The measurement was carried out using 36 ultra-fast LaBr₃(Ce) detectors from the FATIMA setup. This setup, through a fast-timing technique, enables the hard-to-reach short-lifetime values of those excited states. This work presents a new isomeric lifetime measurement for ¹⁹⁰W. Additionally, we obtained the lifetime of the first 2⁺ state of ¹⁹⁰W for the first time using the generalized centroid difference method. In view of the systematic behavior of the R₄₂ , B₂₂ , and B(E2) values, the known spectroscopic data on ¹⁹⁰W matches the predictions for γ-softness. These experimental results have been compared to new theoretical calculations obtained within the interacting boson model (IBM-2). Both experimental and theoretical results agree that the known spectroscopic data on ¹⁹⁰W matches the predictions for the most γ-soft, O(6)-like isotope in the tungsten isotopic chain, approaching the N=126 shell closure. Overall, our study provides new insights into the nuclear structure of exotic nuclei and highlights the importance of advanced experimental techniques in this field.
Typ des Eintrags: | Dissertation | ||||
---|---|---|---|---|---|
Erschienen: | 2023 | ||||
Autor(en): | Sahin, Elif | ||||
Art des Eintrags: | Erstveröffentlichung | ||||
Titel: | Lifetime measurement of the yrast 2⁺ state of ¹⁹⁰W | ||||
Sprache: | Englisch | ||||
Referenten: | Pietralla, Prof. Dr. Norbert ; Aumann, Prof. Dr. Thomas | ||||
Publikationsjahr: | 2023 | ||||
Ort: | Darmstadt | ||||
Kollation: | ix, 147 Seiten | ||||
Datum der mündlichen Prüfung: | 17 Juli 2023 | ||||
DOI: | 10.26083/tuprints-00024403 | ||||
URL / URN: | https://tuprints.ulb.tu-darmstadt.de/24403 | ||||
Kurzbeschreibung (Abstract): | Over the past decades, studies of nuclear structure have led to numerous experiments aimed at understanding the properties of the nucleus. One of the main challenges of this field is the investigation of exotic nuclei, which are characterized by a large excess of neutrons or protons, and are located far from the stability line. To carry out this investigation, experimental techniques capable of producing and detecting these exotic nuclei are required. At the GSI Helmholtzzentrum für Schwerionenforschung in Germany, the DESPEC setup has been utilized to conduct important nuclear structure studies on exotic nuclei. This setup, in combination with the high-intensity primary beams available at GSI, has provided significant opportunities for the investigation of these exotic nuclei. In March 2021, an experiment was conducted at GSI where isotopes of interest were generated through the fragmentation of a primary ²⁰⁸Pb beam with an energy of 1 GeV/u directed at a ⁹Be target. The final products were then identified on an event-by-event basis in the FRS based on their proton number (Z) and mass-to-charge ratio (A/Q), and they were implanted in the DESPEC setup. To further investigate the nuclear structure of these exotic nuclei, measuring the lifetime of excited nuclear states was performed. The measurement was carried out using 36 ultra-fast LaBr₃(Ce) detectors from the FATIMA setup. This setup, through a fast-timing technique, enables the hard-to-reach short-lifetime values of those excited states. This work presents a new isomeric lifetime measurement for ¹⁹⁰W. Additionally, we obtained the lifetime of the first 2⁺ state of ¹⁹⁰W for the first time using the generalized centroid difference method. In view of the systematic behavior of the R₄₂ , B₂₂ , and B(E2) values, the known spectroscopic data on ¹⁹⁰W matches the predictions for γ-softness. These experimental results have been compared to new theoretical calculations obtained within the interacting boson model (IBM-2). Both experimental and theoretical results agree that the known spectroscopic data on ¹⁹⁰W matches the predictions for the most γ-soft, O(6)-like isotope in the tungsten isotopic chain, approaching the N=126 shell closure. Overall, our study provides new insights into the nuclear structure of exotic nuclei and highlights the importance of advanced experimental techniques in this field. |
||||
Alternatives oder übersetztes Abstract: |
|
||||
Status: | Verlagsversion | ||||
URN: | urn:nbn:de:tuda-tuprints-244035 | ||||
Sachgruppe der Dewey Dezimalklassifikatin (DDC): | 500 Naturwissenschaften und Mathematik > 530 Physik | ||||
Fachbereich(e)/-gebiet(e): | 05 Fachbereich Physik 05 Fachbereich Physik > Institut für Kernphysik 05 Fachbereich Physik > Institut für Kernphysik > Experimentelle Kernphysik 05 Fachbereich Physik > Institut für Kernphysik > Experimentelle Kernphysik > Experimentelle Kernstrukturphysik, Radioaktive Ionenstrahlen 05 Fachbereich Physik > Institut für Kernphysik > Experimentelle Kernphysik > Experimentelle Kernstruktur und S-DALINAC |
||||
Hinterlegungsdatum: | 15 Aug 2023 12:03 | ||||
Letzte Änderung: | 08 Okt 2024 11:36 | ||||
PPN: | |||||
Referenten: | Pietralla, Prof. Dr. Norbert ; Aumann, Prof. Dr. Thomas | ||||
Datum der mündlichen Prüfung / Verteidigung / mdl. Prüfung: | 17 Juli 2023 | ||||
Export: | |||||
Suche nach Titel in: | TUfind oder in Google |
Frage zum Eintrag |
Optionen (nur für Redakteure)
Redaktionelle Details anzeigen |