The performance of the cryogenic buffer-gas stopping cell of SHIPTRAP

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:463

Article; Proceedings Paper

Kaleja, O.^1,2,3  Andelic, B.^4,5  Blaum, K.¹  Block, M.^2,3,5  Chhetri, P.^3,6  Droese, C.⁷  Dullmann, Ch. E.^2,3,5  Eibach, M.^3,7  Eliseev, S.¹  Evens, J.⁴  Goetz, S.^2,3,5  Giacoppo, F.^3,5  Kalantar-Nayestanaki, N.⁴  Laatiaoui, M.^2,3,5  Ramirez, E. Minaya⁸  Mistry, A.^3,5  Murboeck, T.³  Raeder, S.^3,4  Schweikhard, L.⁷  Thirolf, P. G.⁹ 

[1] Max Planck Inst Kernphys, Saupfercheckweg 1, D-69117 Heidelberg, Germany

[2] Johannes Gutenberg Univ Mainz, Saarstr 21, D-55122 Mainz, Germany

[3] GSI Helmholtzzentrum Schwerionenforsch, Planckstr 1, D-64291 Darmstadt, Germany

[4] Univ Groningen, KVI CART, Zemikelaan 25, NL-9747 AA Groningen, Netherlands

[5] Helmholtz Inst Mainz, Johann Joachim Becherweg 36, D-55128 Mainz, Germany

[6] Tech Univ Darmstadt, Schlossgartenstr 7, D-64289 Darmstadt, Germany

[7] Univ Greifswald, Inst Phys, Felix Hausdorff Str 6, D-17489 Greifswald, Germany

[8] Univ Paris Sud, Inst Phys Nucl Orsay, CNRS, IN2P3, 15 Rue Georges Clemenceau, F-91406 Orsay, France

[9] Ludwig Maximilians Univ Munchen, Coulombwall 1, D-85747 Garching, Germany

关键词: Cryogenic gas stopping cell;    Stopping and extraction efficiency;    Extraction time;    Penning traps;    Mass spectrometry;    Fusion-evaporation reaction products;    Transfermlum elements nobelium;   

DOI  :  10.1016/j.nimb.2019.05.009

来源: Elsevier

【 摘 要 】

Direct high-precision mass spectrometry of the heaviest elements with SHIPTRAP, at GSI in Darmstadt, Germany, requires high efficiency to deal with the low production rates of such exotic nuclides. A second-generation gas stopping cell, operating at cryogenic temperatures, was developed and recently integrated into the relocated system to boost the overall efficiency. Offline measurements using Ra-223 and (225)AC recoil-ion sources placed inside the gas volume were performed to characterize the gas stopping cell with respect to purity and extraction efficiency. In addition, a first online test using the fusion-evaporation residue No-254 was performed, resulting in a combined stopping and extraction efficiency of 33(5)%. An extraction time of 55(44)ms was achieved. The overall efficiency of SHIPTRAP for fusion-evaporation reaction products was increased by an order of magnitude to 6(1)%. This will pave the way for direct mass spectrometry of heavier and more exotic nuclei, eventually in the region of superheavy elements with proton numbers Z >= 104.

【 授权许可】

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