The TransActinide Separator and Chemistry Apparatus (TASCA) at GSI – Optimization of ion-optical structures and magnet designs

Semchenkov, A.; Brüchle, W.; Jäger, E.; Schimpf, E.; Schädel, M.; Mühle, C.; Klos, F.; Türler, Α.; Yakushev, A.; Белов, А. В.; Belyakova, T.; Kaparkova, Marina V.; Kukhtin, V.; Lamzin, E.; Sytchevsky, S.

doi:10.1016/j.nimb.2008.05.132

Cited by 97 publications

(58 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…37,38 After deexcitation by evaporation of three or four neutrons, the resulting 288,289 Fl nuclei recoiled from the target into the separator TASCA operated in the "Small Image Mode". 32 The primary beam and unwanted nuclear reaction products were deflected inside the dipole magnet to a beam stop, while Fl was guided to the focal plane (Figure 1). Magnets were set to focus ions with a magnetic rigidity, B·ρ, of 2.27 T·m into a ~(3 x 5) cm 2 area in TASCA's focal plane.…”

Section: Methodsmentioning

confidence: 99%

Superheavy Element Flerovium (Element 114) Is a Volatile Metal

et al. 2014

View full text Add to dashboard Cite

Superheavy Element Flerovium (Element 114) Is a Volatile MetalAccess to the published version may require subscription. Superheavy Element Flerovium (Element 114) is a Volatile MetalAlexander Yakushev †, , Jacklyn M. ABSTRACT: The electron shell structure of superheavy elements, i.e., elements with atomic number Z ≥ 104, is influenced by strong relativistic effects caused by the high Z. Early atomic calculations on element 112 (copernicium, Cn) and element 114 (flerovium, Fl) having closed and quasiclosed electron shell configurations of 6d 10 7s 2 and 6d 10 7s 2 7p 1/2 , respectively, predicted them to be noble gas-like due to very strong relativistic effects on the 7s and 7p 1/2 valence orbitals. Recent fully relativistic calculations studying Cn and Fl in different environments suggest them to be less reactive compared to their lighter homologs in the groups, but still exhibiting a metallic character. Experimental gassolid chromatography studies on Cn have, indeed, revealed a metal-metal bond formation with Au. In contrast to this, for Fl, the formation of a weak bond upon physisorption on a Au surface was inferred from first experiments. Here, we report on a gas-solid chromatography study of the adsorption of Fl on a Au surface. Fl was produced in the nuclear fusion reaction 244 Pu( 48 Ca, 3-4n) 288,289 Fl and was isolated in-flight from the primary 48 Ca beam in a physical recoil separator. The adsorption behavior of Fl, its nuclear α-decay product Cn, their lighter homologs in groups 14 and 12, i.e., Pb and Hg, and the noble gas Rn were studied simultaneously by isothermal gas chromatography and thermochromatography. Two Fl atoms were detected. They adsorbed on a Au surface at room temperature in the first, isothermal part, but not as readily as Pb and Hg. The observed adsorption behavior of Fl points to a higher inertness compared to its nearest homolog in the group, Pb. However, the measured lower limit for the adsorption enthalpy of Fl on a Au surface points to the formation of a metal-metal bond of Fl with Au. Fl is the least reactive element in the group, but still a metal.

show abstract

Section: Methodsmentioning

confidence: 99%

Superheavy Element Flerovium (Element 114) Is a Volatile Metal

et al. 2014

View full text Add to dashboard Cite

show abstract

“…These are the High Transmission Mode (HTM) and the Small Image Mode (SIM) [5]. When operated in SIM the transmission is typically 35% for evaporation residues in reactions aimed to produce heavy or superheavy elements [8].…”

Section: Tasca In Small Image Mode (Tasispec)mentioning

confidence: 99%

“…The SIM has the advantage of a very small focal plane image. The residues end up in a slightly elliptical image of about 3 cm in diameter [5], thus allowing high-resolution Ge-and Sidetectors to be placed around it in an very compact way.…”

Section: Tasca In Small Image Mode (Tasispec)mentioning

confidence: 99%

See 1 more Smart Citation

A Geant4 simulation package for the TASISpec experimental detector setup

Sarmiento

Andersson

Rudolph

2012

Nuclear Instruments and Methods in Physics Research Section A:

View full text Add to dashboard Cite

The experimental detector setup TASISpec (TASCA in Small Image mode Spectroscopy) comprises composite Geand highly segmented Si-detectors. The setup is constructed to provide multi-coincidence spectroscopic data between γ-rays, X-rays, conversion electrons, fission fragments, and α-particles for heavy and superheavy elements (Z ≥ 100).The full array has been virtually constructed using the Geant4 simulation toolkit. The simulations will not only be used to explore the possibilities of the detector setup itself. More important, however, they will also shed light on the nuclear structure of the heaviest elements. This can be done by comparing the simulated detector response of complex decay modes with the experimental data. Such an iterative or 'self-consistent' way to understand experimental observables will provide more reliability when disentangling the data and deducing experimental decay schemes.

show abstract

“…In this most recent development, which constitutes a breakthrough in SHE chemistry, gasfilled magnetic recoil-separators are applied between the target and the recoil chamber -now commonly termed Recoil Transfer Chamber, RTC [116][117][118]. Pioneering work has been performed at the BGS [113,116,119,120] followed by new developments and experiments at the TASCA [110][111][112][121][122][123], the GARIS [117,[124][125][126][127], which had also been used in combination with an IGISOL system before [128], and the DGFRS [129]. A scheme of such a setup, as used at the GARIS, is shown in Fig.…”

Section: Physical Pre-separatorsmentioning

confidence: 99%

Chemistry of superheavy elements

Schädel

2012

Radiochimica Acta

Self Cite

View full text Add to dashboard Cite

Summary. The chemistry of superheavy elements -or transactinides from their position in the Periodic Table -is summarized. After giving an overview over historical developments, nuclear aspects about synthesis of neutron-rich isotopes of these elements, produced in hot-fusion reactions, and their nuclear decay properties are briefly mentioned. Specific requirements to cope with the one-atom-at-a-time situation in automated chemical separations and recent developments in aqueous-phase and gas-phase chemistry are presented. Exciting, current developments, first applications, and future prospects of chemical separations behind physical recoil separators ("pre-separator") are discussed in detail. The status of our current knowledge about the chemistry of rutherfordium (Rf, element 104), dubnium (Db, element 105), seaborgium (Sg, element 106), bohrium (Bh, element 107), hassium (Hs, element 108), copernicium (Cn, element 112), and element 114 is discussed from an experimental point of view. Recent results are emphasized and compared with empirical extrapolations and with fully-relativistic theoretical calculations, especially also under the aspect of the architecture of the Periodic Table.

show abstract

The TransActinide Separator and Chemistry Apparatus (TASCA) at GSI – Optimization of ion-optical structures and magnet designs

Cited by 97 publications

References 17 publications

Superheavy Element Flerovium (Element 114) Is a Volatile Metal

Superheavy Element Flerovium (Element 114) Is a Volatile Metal

A Geant4 simulation package for the TASISpec experimental detector setup

Chemistry of superheavy elements

Contact Info

Product

Resources

About