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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 223Ra and 225Ac 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 254No 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. [ABSTRACT FROM AUTHOR]

In this paper, the major upgrades and technical improvements of the buffer gas handling system for the cryogenic stopping cell of the FRS Ion Catcher at GSI/FAIR (in Darmstadt, Germany) are described. The upgrades include implementation of new gas lines and gas purifiers to achieve a higher buffer gas cleanliness for a more efficient extraction of reactive ions as well as suppression of the molecular background ionized in the stopping cell. Furthermore, additional techniques have been implemented for improved monitoring and quantification of the purity of the helium buffer gas. [ABSTRACT FROM AUTHOR]

The Reactions with Relativistic Radioactive Beams (R 3 B) collaboration of the Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany, has constructed an experimental setup to perform fundamental studies of nuclear matter, using as a probe reactions with exotic nuclei at relativistic energies. Among the various detection systems, one of the most recent upgrades consists of the installation of a large area, around 2 m 2 , multi-gap Resistive Plate Chamber (RPC). The chamber is equipped with twelve 0. 3 mm gaps and readout by 30 mm pitch strips, exhibiting a timing precision down to 50 ps and efficiencies above 98% for minimum ionizing particles in a previous characterization of the detector. The RPC was part of the setup of the FAIR Phase 0 experiment that focused on measuring for the first time, in spring 2022, nucleon–nucleon short-range correlations (SRC) inside an exotic nucleus (16C). The excellent timing precision of this detector will allow the measurement of the forward emitted proton momentum with a resolution of around 1%. In beam measurements show an RPC efficiency above 95% and a time precision better than 100 ps (including the contribution of a reference scintillator and the momentum spread of the particles) for forward emitted particles. [ABSTRACT FROM AUTHOR]

The proposed international Facility for Antiproton and Ion Research (FAIR) at GSI-Darmstadt, will be a source of exotic radionuclidic beam and is expected to be operational in 2016. The facility will deliver 2 GeV/u to 45 GeV/u beam covering the entire range of the periodic table with the intensities three orders of magnitude higher than that available anywhere in the world today. This facility will serve all areas of fundamental sciences including nuclear physics, physics at extreme density conditions like neutron stars, plasma and laser physics, hadron physics and applied areas in chemistry, biology and material sciences. In this article, we discuss briefly the FAIR facility, with special emphasis on Indian participation. [ABSTRACT FROM AUTHOR]

Abstract: The electron–ion scattering experiment ELISe is part of the installations envisaged at the new experimental storage ring at the International Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. It offers an unique opportunity to use electrons as probe in investigations of the structure of exotic nuclei. The conceptual design and the scientific challenges of ELISe are presented. [Copyright &y& Elsevier]

Recent developments in precision mass spectrometry of radioactive isotopes (RI) and some selected related physics subjects are reviewed. In the last decades, besides conventional technologies in RI beam experiments, mass spectrometry of short-lived nuclei has significantly boosted its performance in terms of sensitivity and precision. Whereas single-path measurements are still employed for studies of the most rarely produced short-lived nuclides, though at a moderate precision level, modern methods are based on the storage of freshly produced exotic nuclei for a period of time. One of the biggest achievements in this direction so far is the Penning-trap mass spectrometry, where the highest mass accuracies of typically 1 0 − 8 are routinely obtained for radioactive nuclei. New precise mass values contribute to the developments of nuclear structure and nuclear astrophysics as well as are used for testing fundamental interactions and symmetries. Having the goal to study the most exotic short-lived nuclei in the vicinity of the neutron and proton drip lines, new highly efficient and fast techniques, such as multi-reflection time-of-flight spectrometers (MR-TOF) and mass spectrometry based on heavy-ion storage rings, are steadily gaining importance. Thanks to their fast measurement schemes both, MR-TOFs and storage rings, have successfully proven their high potential by accessing short-lived nuclei, where the mass accuracies down to 1 0 − 7 and even below were reported. Currently, the MR-TOF systems dedicated to mass measurements are in operation or in a planning phase at basically all RI beam facilities. The storage rings for radioactive beams are in use at three accelerator complexes, namely GSI in Darmstadt, Germany, IMP in Lanzhou, P. R. China, and RIKEN in Saitama, Japan. Although the progress of RI beam facilities was enormous in the last decades and new, more powerful facilities are expected to come in operation in the coming few years, some regions on the nuclidic chart will remain inaccessible for experiments. Therefore, the properties of such nuclides, in particular heavy neutron-rich nuclei, will have to be determined through theoretical calculations. It is an important quest to use the new precision masses for constraining and further developing of reliable nuclear theory. There are various models to describe atomic (nuclear) ground-state masses ranging from macroscopic approaches with microscopic corrections to ab-initio calculations based on nucleon–nucleon interactions. In this review article we focus on recent experimental challenges and findings as well as on the cutting-edge experimental technologies and mass formula theories. [ABSTRACT FROM AUTHOR]

Adjacent to the existing accelerator complex of the GSI Helmholtz Centre for Heavy Ion Research at Darmstadt, Germany, the Facility for Antiproton and Ion Research (FAIR) substantially expands research goals and technical possibilities. It will provide worldwide unique accelerator and experimental facilities allowing for a large variety of unprecedented fore-front research in hadron, nuclear and atomic physics as well as applied sciences which will be described briefly in this paper. The start version of FAIR, the so-called Modularized Start Version, will deliver first beams in 2017/2018. As an example the paper presents research efforts on strangeness at FAIR using heavy ion collisions, exotic nuclei from fragmentation and antiprotons to tackle various topics in this area. In particular hypernuclei and metastable exotic multi-hypernuclear objects will be investigated. [ABSTRACT FROM AUTHOR]