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Erzeugung exotischer Atomkerne. Krebsnebel. Supernova beobachtet 1054. Der Ursprung der Elemente. Nukleosynthese nach dem Urknall. Kernfusion in Sternen. Neutroneneinfang in Roten Riesensternen oder Supernovae. Geburt und Tod der Sterne. Zwiebelschalenstruktur kurz vor Explosion.
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Krebsnebel Supernova beobachtet 1054 Der Ursprung der Elemente Nukleosynthese nach dem Urknall Kernfusion in Sternen Neutroneneinfang in Roten Riesensternen oder Supernovae
Geburt und Tod der Sterne Zwiebelschalenstruktur kurz vor Explosion 8M M 15M Supernova II 1.4M Mcore 2M Neutronen Stern M 15M Supernova IIa M 2M Schwarzes Loch M 8M Roten Riese Weiβer Zwerg
Fusion in Sternen Der Ursprung der Elemente number of protons Nucleosynthese in Supernova-Explosionen: Schneller Neutroneneinfang durch instabile (neutronenreiche) Isotope number of neutrons
Reaktionsmechanismen zur Erzeugung radioaktiver Strahlen Protonen-indizierte Reaktionen Schwerionen-induzierte Reaktionen
Fragmentation im Fluge Ionen-Separation on-line „ISOL“
Zwei moderne Methoden zur Erzeugung und Untersuchung seltener Isotope Gestoppte und wiederbeschleunigte Ionen „Ionen Separation Online (ISOL): Fragmentation „im Fluge“ (IF): Relativistische Schwerionenstrahlen Intensive Protonenstrahlen Heißes, dickes Target: Targetfragmentation Dünnes Target: Projektilfragmentation Ionenquelle ms - s Fragmentseparator Massenseparator geringer Auflösung s Ionenkühlung Speicherring Ionenfallen
ISOLDE (CERN) Strahl aus dem PS Booster: Verbund aus 4 kleinen Synchrotrons liefert 1 GeV Protonen, 3.21013/s (alle 1.2 s) Some of the targets used at ISOLDE consist of molten metals kept at temperatures from 700o C and up to about 1400o C. Such targets are characterized by a relatively long release time of the produced isotopes and a typical time constant of the release is about 30 seconds. Faster release times, in the order of one second or less, can be obtained, if target material in the form of refractory metal powder, metals or carbides is used at temperatures above 2000o C. An expected decrease in the release time due to the "shock-wave" effect of the pulsed proton beam has been observed. Time constants down to some tenths of a second can be reached for the fastest targets. Oberflächen-Ionenquelle
Separatoren an ISOLDE (CERN) The second separator, the High Resolution Separator (HRS), is equipped with two bending C-magnets with bending angles 90° and 60° degrees, respectively. At the moment one single mass, with a resolution of about M/M=5.000, can be separated routinely with the HRS separator. The calculated beam profiles for the masses 99, 100 and 101 are shown in the figure. It will be possible to achieve a maximal resolution of more than 30.000. The ISOLDE PS-Booster facility is equipped with two isotope separators. The General Purpose Separator (GPS) is designed to allow three beams, within a mass range of ± 15%, to be selected and delivered to the experimental hall. The magnet is double focussing H-magnet with a bending angle of 70° and a mean bending radius of 1.5 m. The mass resolving power is M/M=2400.
Reichweite und Energieverlust geladener Teilchen in Materie nach Bethe-Bloch
GSI: Kombination von relativistischen Ionenstrahlen, Fragmentseparator und Speicherring (oder Neutronendetektor)