New results with stored exotic nuclei at relativistic energies

Geißel, H.; Litvinov, Yu. A.; Attallah, F.; Beckert, K.; Béller, P.; Bosch, F.; Boutin, D.; Faestermann, T.; Falch, M.; Franzke, B.; Hausmann, M.; Hellström, M.; Kaza, E.; Kerscher, Th.; Klepper, O.; Kluge, H.-J.; Kozhuharov, C.; Kratz, K. L.; Litvinov, S.; Löbner, K. E. G.; Maier, L.; Matoš, M.; Münzenberg, G.; Nolden, F.; Novikov, Yu. N.; Ohtsubo, T.; Ostrowski, A. N.; Patyk, Z.; Pfeiffer, B.; Portillo, M.; Radon, T.; Scheidenberger, C.; Шишкин, В. А.; Stadlmann, J.; Steck, M.; Viera, David; Weick, H.; Winkler, M.; Wöllnik, H.; Yamaguchi, Takayuki

doi:10.1016/j.nuclphysa.2004.09.030

Cited by 59 publications

(10 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Cooling times can be significantly reduced when electron cooling is used in combination with stochastic precooling. With this setup a minimum time of ∼ 1 s can be obtained, leading to a lower limit on the lifetime of ions measured with SMS [28]. Measurement times can be further reduced if the ESR is operated in isochronous mode [25].…”

Section: Methodsmentioning

confidence: 99%

Long-lived isomers in neutron-richZ=72–76 nuclides

et al. 2012

Self Cite

View full text Add to dashboard Cite

A study of neutron-rich isotopes in the A = 185 region of the nuclear chart has uncovered long-lived (>1 s) isomers in several isotopes of hafnium, tantalum, tungsten, rhenium, and osmium. The region was accessed via the use of projectile fragmentation with the UNILAC-SIS accelerators at GSI. Fragmentation products of 197 Au were passed through the fragment separator (FRS) and injected into the experimental storage ring (ESR), where single-ion identifications could be made. Evidence is presented for isomers in 183,184,186 Hf, 186,187 Ta, 186 W, 190,192,194 Re, and 195 Os with excitation energies in the range of 0.1-3.0 MeV. The lightest of these nuclides have well deformed prolate shapes, while the heaviest are transitional and susceptible to shape changes. Their properties are interpreted with the help of multi-quasiparticle and potential-energy-surface calculations.

show abstract

Section: Methodsmentioning

confidence: 99%

Long-lived isomers in neutron-richZ=72–76 nuclides

et al. 2012

Self Cite

View full text Add to dashboard Cite

show abstract

“…The key to this progress is the application of non-Liouvillean optics (Geissel FIGURE 43. Schottky frequency spectra of the decay of 207m Tl 81þ fragments and the corresponding decay curve (data from Geissel et al, 2004). The combination of stochastic and electron cooling yields access to short-lived ions down to the 1 sec range.…”

Section: Futurementioning

confidence: 99%

Mass and lifetime measurements of exotic nuclei in storage rings

Franzke

Geißel

Münzenberg

2008

Mass Spectrometry Reviews

222

189

View full text Add to dashboard Cite

Mass and lifetime measurements lead to the discovery and understanding of basic properties of matter. The isotopic nature of the chemical elements, nuclear binding, and the location and strength of nuclear shells are the most outstanding examples leading to the development of the first nuclear models. More recent are the discoveries of new structures of nuclides far from the valley of stability. A new generation of direct mass measurements which allows the exploration of extended areas of the nuclear mass surface with high accuracy has been opened up with the combination of the Experimental Storage Ring ESR and the FRragment Separator FRS at GSI Darmstadt. In-flight separated nuclei are stored in the ring. Their masses are directly determined from the revolution frequency. Dependent on the half-life two complementary methods are applied. Schottky Mass Spectrometry SMS relies on the measurement of the revolution frequency of electron cooled stored ions. The cooling time determines the lower half-life limit to the order of seconds. For Isochronous Mass Spectrometry IMS the ring is operated in an isochronous ion-optical mode. The revolution frequency of the individual ions coasting in the ring is measured using a time-of-flight method. Nuclides with lifetimes down to microseconds become accessible. With SMS masses of several hundreds nuclides have been measured simultaneously with an accuracy in the 2 x 10(-7)-range. This high accuracy and the ability to study large areas of the mass surface are ideal tools to discover new nuclear structure properties and to guide improvements for theoretical mass models. In addition, nuclear half-lives of stored bare and highly charged ions have been measured. This new experimental development is a significant progress since nuclear decay characteristics are mostly known for neutral atoms. For bare and highly charged ions new nuclear decay modes become possible, such as bound-state beta decay. Dramatic changes in the nuclear lifetime have been observed in highly charged ions compared to neutral atoms due to blocking of nuclear decay channels caused by the modified atomic interaction. High ionization degrees prevail in hot stellar matter and thus these experiments have great relevance for the understanding of the synthesis of elements in the universe and astrophysical scenarios in general.

show abstract

“…For electron-cooled ions, the mass resolving power of about 750000 is reached, which is sufficient to separate isobars and even low-lying isomers by their revolution frequencies in the ring. The intensities of stored ions are continuously monitored with non-destructive time-resolved Schottky spectrometry [54][55][56][57][58]. In addition, the decay/reaction products can be intercepted by dedicated particle detectors [59,60].…”

mentioning

confidence: 99%