Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Yakushev, A.*; Lens, L.*; Dllmann, Ch. E.*; Khuyagbaatar, J.*; Jger, E.*; Krier, J.*; Runke, J.*; Albers, H. M.*; Asai, Masato; Block, M.*; et al.
Frontiers in Chemistry (Internet), 10, p.976635_1 - 976635_11, 2022/08
Times Cited Count:11 Percentile:81.01(Chemistry, Multidisciplinary)Flerovium (Fl, element 114) is the heaviest element chemically studied so far. The first chemical experiment on Fl suggested that Fl is a noble-gas-like element, while the second studies suggested that Fl has a volatile-metal-like character. To obtain more reliable conclusion, we performed further experimental studies on Fl adsorption behavior on Si oxide and gold surfaces. The present results suggest that Fl is highly volatile and less reactive than the volatile metal, Hg, but has higher reactivity than the noble gas, Rn.
Khuyagbaatar, J.*; Yakushev, A.*; Dllmann, Ch. E.*; Ackermann, D.*; Andersson, L.-L.*; Asai, Masato; Block, M.*; Boll, R. A.*; Brand, H.*; Cox, D. M.*; et al.
Physical Review C, 102(6), p.064602_1 - 064602_9, 2020/12
Times Cited Count:45 Percentile:98.21(Physics, Nuclear)A search for production of the superheavy elements with atomic numbers 119 and 120 was performed in the Ti+Bk and Ti+Cf fusion-evaporation reactions, respectively, at the gas-filled recoil separator TASCA. Over four months of irradiation, neither was detected at cross-section sensitivity levels of 65 and 200 fb, respectively. The non-observation of elements 119 and 120 is discussed within the concept of fusion-evaporation reactions including various theoretical predictions on the fission-barrier heights of superheavy nuclei in the region of the island of stability.
Khuyagbaatar, J.*; Yakushev, A.*; Dllmann, Ch. E.*; Ackermann, D.*; Andersson, L.-L.*; Asai, Masato; Block, M.*; Boll, R. A.*; Brand, H.*; Cox, D. M.*; et al.
Physical Review C, 99(5), p.054306_1 - 054306_16, 2019/05
Times Cited Count:24 Percentile:90.97(Physics, Nuclear)We have performed an experiment to synthesize the element 117 (Ts) with the Ca+Bk fusion reaction. Four -decay chains attributed to the element 117 were observed. Two of them were long decay chains which can be assigned to the one originating from the decay of Ts. The other two were short decay chains which are consistent with the one originating from the decay of Ts. We have compared the present results with the literature data, and found that our present results mostly confirmed the literature data, leading to the firm confirmation of the synthesis of the element 117.
Lens, L.*; Yakushev, A.*; Dllmann, Ch. E.*; Asai, Masato; Ballof, J.*; Block, M.*; David, H. M.*; Despotopulos, J.*; Di Nitto, A.*; Eberhardt, K.*; et al.
Radiochimica Acta, 106(12), p.949 - 962, 2018/12
Times Cited Count:8 Percentile:61.87(Chemistry, Inorganic & Nuclear)Online gas-solid adsorption studies with single atom quantities of Hg, Tl, and Pb on SiO and Au surfaces were carried out using short-lived radioisotopes with half-lives in the range of 4-49 s. This is a model study to measure adsorption enthalpies of superheavy elements Cn, Nh, and Fl. The short-lived isotopes were produced and separated by the gas-filled recoil separator TASCA at GSI. The products were stopped in He gas, and flushed into gas chromatography columns made of Si detectors whose surfaces were covered by SiO or Au. The short-lived Tl and Pb were successfully measured by the Si detectors with the SiO surface at room temperature. On the other hand, the Hg did not adsorb on the SiO surface, but adsorbed on the Au surface. The results demonstrated that the adsorption properties of short-lived Hg, Tl, and Pb could be studied with this setup, and that this method is applicable to the experiment for Cn, Nh, and Fl.
Khuyagbaatar, J.*; Yakushev, A.*; Dllmann, Ch. E.*; Ackermann, D.*; Andersson, L.-L.*; Asai, Masato; Block, M.*; Boll, R. A.*; Brand, H.*; Cox, D. M.*; et al.
Physical Review Letters, 112(17), p.172501_1 - 172501_5, 2014/05
Times Cited Count:210 Percentile:98.42(Physics, Multidisciplinary)The superheavy element with atomic number 117 was produced in the Ca + Bk fusion reaction using the gas-filled recoil separator TASCA at GSI in Germany. This result verified the previous result of the discovery of new element 117 reported by Flerov Laboratory of Nuclear Reactions in Russia, which makes certain the synthesis and discovery of element 117 in human history. On the other hand, the last nucleus in the decay chain from the element 117 was assigned to be the unknown nucleus Lr instead of the previously reported Db, and Db was found to be the -decaying nucleus with very long half-life.
Yakushev, A.*; Gates, J. M.*; Trler, A.*; Schdel, M.; Dllmann, Ch. E.*; Ackermann, D.*; Andersson, L.-L.*; Block, M.*; Brchle, W.*; Dvorak, J.*; et al.
Inorganic Chemistry, 53(3), p.1624 - 1629, 2014/02
Times Cited Count:105 Percentile:98.87(Chemistry, Inorganic & Nuclear)We report on a gas-solid chromatography study of the adsorption of element 114 (flerovium, Fl) on a Au surface. Fl was produced in the nuclear fusion reaction Pu(Ca, 3-4n)Fl and was isolated in-flight from the primary beam in a physical recoil separator. The adsorption behavior of Fl, its nuclear -decay product Cn, their lighter homologues 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, but not as readily as Pb and Hg. The observed adsorption behavior of Fl points to a higher inertness compared to its nearest homologue 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.
Dvorak, J.*; Brchle, W.*; Dllmann, Ch. E.*; Dvorakova, Z.*; Eberhardt, K.*; Eichler, R.*; Jger, E.*; Nagame, Yuichiro; Qin, Z.*; Schdel, M.*; et al.
Physical Review C, 79(3), p.037602_1 - 037602_4, 2009/05
Times Cited Count:17 Percentile:69.83(Physics, Nuclear)no abstracts in English
Dvorak, J.*; Brchle, W.*; Chelnokov, M.*; Dllmann, Ch. E.*; Dvorakova, Z.*; Eberhardt, K.*; Jger, E.*; Krcken, R.*; Kuznetsov, A.*; Nagame, Yuichiro; et al.
Physical Review Letters, 100(13), p.132503_1 - 132503_4, 2008/04
Times Cited Count:125 Percentile:94.89(Physics, Multidisciplinary)Dvorak, J.*; Brchle, W.*; Chelnokov, M.*; Dllmann, Ch. E.*; Dvorakova, Z.*; Eberhardt, K.*; Jger, E.*; Krcken, R.*; Kuznetsov, A.*; Nagame, Yuichiro; et al.
Physical Review Letters, 100(13), p.132503_1 - 132503_4, 2008/04
The analysis of a large body of heavy ion fusion reaction data with medium-heavy projectiles (6Z18) and actinide targets suggests a disappearance of the 3 exit channel with increasing atomic number of the projectile. Here, we report a measurement of the excitation function of the reaction Cm(Mg,)Hs and the observation of the new nuclide Hs produced in the 3 evaporation channel at a beam energy well below the Bass fusion barrier with a cross section comparable to the maxima of the 4 and 5 channels. This indicates the possible discovery of new neutron-rich transactinide nuclei using relatively light heavy ion beams of the most neutron-rich stable isotopes and actinide targets.
Dvorak, J.*; Brchle, W.*; Chelnokov, M.*; Dressler, R.*; Dllmann, Ch. E.*; Eberhardt, K.*; Gorshkov, V.*; Jger, E.*; Krcken, R.*; Kuznetsov, A.*; et al.
Physical Review Letters, 97(24), p.242501_1 - 242501_4, 2006/12
Times Cited Count:152 Percentile:96.00(Physics, Multidisciplinary)no abstracts in English