Correlated decay chains

In a later experiment (Tiirler et al., 1999), the isothermal temperature was varied to obtain the adsorption enthalpy for Sg. The yield of short-lived W isotopes from reactions on Gd incorporated in the target was also measured at the same time. An adsorption enthalphy of-96 1 kJ mol 1 was obtained for the dioxydichloride of W in agreement with the previous measurement. Based on 11 events attributable to Sg, an adsorption enthalpy of -100 4 kJ mol-1 or 96 1 kJ mol 1 was obtained depending on the Sg half-life used in the Monte Carlo calculations. Thus, the experimental results confirmed the theoretically predicted volatility sequence of Mo > W > Sg. From an analysis of the decay properties of the correlated decay chains detected in these experiments, Tiirler et al. (1998) were able to recommend better half-lives and cross sections of 7.4 + 3.3/ - 2.7 s and approximately 0.24 nb for 265Sg and of 21 + 20/ - 12 s and approximately 0.025 nb for 266Sg for 22Ne beam energies between 120 and 124 MeV. 

In the diagram of Fig. 7.7 we show all possible pair correlations for the finite open linear case with m = 6. The parameters are still the same h = 0.01, K=4, and Ti = 0.1. Note that there are three different nn pair correlations gj 2= 5 g, 2,3 = 4,5 and gj 4. There are two different second-n pair correlations, gj 3 and g24 (only the different ones are indicated in the diagram). There are two third-n pair correlations, gj 4 and g2 5- There is one fourth-n pair correlation gj 5 and one sixth- n pair correlation gj g. It should also be noted that, as in the infinite chain (m °o) case, the correlations decay with distance /. 

Throughout the experiment close to 180.000 samples were measured. A total of 6 genetically linked decay chains attributed to the decay of 267Bh were observed four at an isothermal temperature of 180°C, two at 150°C and none at 75°C. Due to a small contamination with Po and Bi nuclides, and a statistical treatment of this background, 1.3 of the 4 decay chains observed at 180°C had to be attributed to accidental correlations unrelated to the decay of 267Bh. At 150°C this correction was only 0.1 out of 2 observed decay chains. The properties of the observed decay chains are shown in Figure 21. 

In the only studies so far reported (2005), hassium atoms were oxidized to a very volatile oxide (thought to be HSO4 by analogy with Ru and Os - its absorption enthalpy is comparable with that of OSO4), and deposited on an NaOH surface. Six correlated o -decay chains of Hs were observed and attributed to Na2[Hs04(OH)2], sodium hassate(viii), by analogy with osmium, the 5d homologue of Hs. 

Another model is the wormlike chain model [2], Its measure of stiffness is the persistence length, which is half the Kuhn length. The persistence and Kuhn lengths characterize the number of bonds over which orientational correlations decay to zero along the chain. These are simplified models of bond correlations. A better treatment, which we won t explore here, is the rotational isomeric state model [1, 3], which accounts not only for the angles and lengths of chemical bonds, but also for the different statistical weights of the various possible bond conformations. 

The first successful gas chemical studies of volatile halides of Rf [109] involving the unambiguous detection of time correlated nuclear a decay chains... 

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