Recoil separator

Table lb. Recoil separations for isotope production or enrichment... 

Using a recoil separation technique, however, [STE85] very clean spectra (Fig. 4b) could be obtained. The B(E2) values extracted for I90 i92pt) perfectly extend the trend observed in the heavier isotopes (Fig. 3). 

There was also great uncertainty of the production yields for SHEs. Closely related to the fission probability of SHEs in the ground-state, the survival of the compound nuclei formed after complete fusion was difficult to predict. Even the best choice of the reaction mechanism, fusion or transfer of nucleons, was critically debated. However, as soon as experiments could be performed without technical limitations, it turned out that the most successful methods for the laboratory synthesis of heavy elements are fusion-evaporation reactions using heavy-element targets, recoil-separation techniques, and the identification of the nuclei by generic ties to known daughter decays after implantation into position-sensitive detectors [13-15],... 

The identification of the first transuranium elements was by chemical means. In the early 1960s physical techniques were developed which allowed for detection of nuclei with lifetimes of less than one second at high sensitivity. A further improvement of the physical methods was obtained with the development of recoil separators and large area position sensitive detectors. As a prime example for such instruments, we will describe the velocity filter SHIP (Separator for Heavy-Ion reaction Products) and its detector system, which were developed at the UNILAC. The principle of separation and detection techniques used in the other laboratories is comparable. 

In contrast to the recoil-stopping methods, as used in He-jet systems or mass separators, where ion sources are utilized, recoil-separation techniques use the ionic charge and momentum of the recoiling fusion product obtained in the reaction process. Spatial separation from the projectiles and other reaction products is achieved by combined electric and magnetic fields. The... 

Yakushev, A http //159.93.28.88/www-nekho/chem 112.html, Yakushev, A. First Chemistry Experiments with Element 112 . In Workshop on Recoil Separator for Superheavy Element Chemistry , GSI, Darmstadt, Germany, March 20-21, 2002, http //www.gsi.de/chemsep/images/Element%20112.pdf... 

In application of the recoil separation during Irradiation of solid substances, the target material should be very thin... 

Fission gas recoil. Another interesting example of recoil separation in the (n,fisslon) reaction is the separation technique for krypton fission products from a uranium foil target (202). The target, an enriched uranium film (0.3 mg/cm ) deposited on a 1.6-cm diameter platinum plate, was mounted as shown in Fig. 1 at one end of a vacuum-tight recoil chamber... 

Turner S W P, Cabodi M, Craighead H G (2002). Confinement-induced entropic recoil of single DNA molecules in nanofluidic structure. Phys. Rev. Let. 88(12) 128103. Cabodi M, Turner S W P, Craighead H G (2002). Entropic recoil separation of long DNA molecules. Anal. Chem. 74 5169-5174. 

GARIS RIKEN gas-filled recoil separator Morita et al. 1992... 

DGFRS JINR gas-filled recoil separator Lazarev et al. 1993, Subotic et al. 2002... 

RITU JYFL gas-filled recoil separator Leino et al. 1995... 

TASCA GSI , gas-filled recoil separator Schadel 2007, Semchenkov et al. 2008... 

The gas-filled recoil separator RITU (Recoil Ion Transport Unit) and the recoil mass separator FMA (fragment mass analyzer) in conjunction with germanium (Ge) detector arrays... 

Scheme of recoil separator RITU (Recoil Ion Transport Unit) (Munzenberg 1997)... 

Layout of the Dubna gas-filled recoil separator (DGFRS) with target wheel, dipole magnet, and detector station (Oganessian 2007). A schematic view of the detector system is displayed in the upper part of the figure... 

The expected half-lives of the evaporation residues with Z > 112 were sufficiently short that recoil-separation techniques and position-sensitive detectors similar to those applied in cold-fusion reactions were used in the discovery experiments. A fundamental drawback to the method is that the a-decay chains reconstructed from the detector data do not provide a connection to the known nuclei. The decay chains are terminated by spontaneous fission as they leave the... 

Tsyganov, Yu.S. The Dubna gas-filled recoil separator status and developments. J. Phys. G25, 937-940 (1999)... 

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