beta-delayed fission in proton-rich nuclei in the lead region

This thesis describes the results of an experimental study of beta-delayed fission (BDF) properties of 194,196At and 200,202Fr. The experiments were performed at the ISOLDE facility in CERN-Geneva (Switzerland). Chapter 1 presents the research subject and a global motivation to study the nuclear fission process. Chapter 2 provides a short overview of the relevant nuclear decay modes, as well as current state-of-the-art experimental and theoretical (beta-delayed) fission studies. Since the studied radioactive isotopes have a short lifetime, they have to be produced in a dedicated facility. The experiments presented in this work were performed at the ISOLDE facility in CERN, as described in chapter 3. The data on the BDF of 200,202Fr and 194,196At were analyzed using the techinques described in chapter 4. The extracted BDF properties, including fission-fragment mass- and energy distributions, are discussed in a published paper, which is incorporated in chapter 5. Chapter 6 describes a systematic study of beta-delayed fission partial half-lives across the nuclear chart, also published in a peer-reviewed article. The conclusion of this work as well as an outlook for future research are presented in chapter 7.