T. Dickel

High-performance multiple-reflection time-of-flight mass spectrometers for research with exotic nuclei and for analytical mass spectrometry

A class of multiple-reflection time-of-flight mass spectrometers (MR-TOF-MSs) has been developed for research with exotic nuclei at present and future accelerator facilities such as GSI and FAIR (Darmstadt), and TRIUMF (Vancouver). They can perform highly accurate mass measurements of exotic nuclei, serve as high-resolution, high-capacity mass separators and be employed as diagnostics devices to monitor the production, separation and manipulation of beams of exotic nuclei. In addition, a mobile high-resolution MR-TOF-MS has been developed for in situ applications in analytical mass spectrometry ranging from environmental research to medicine. Recently, the MR-TOF-MS for GSI and FAIR has been further developed. A novel RF quadrupole-based ion beam switchyard has been developed that allows merging and splitting of ion beams as well as transport of ions into different directions. It efficiently connects a test and reference ion source and an auxiliary detector to the system. Due to an increase in the kinetic energy of the ions in the time-of-flight analyzer of the MR-TOF-MS, a given mass resolving power is now achieved in less than half the time-of-flight. Conversely, depending on the time-of-flight, the mass resolving power has been increased by a factor of more than two.

The Soreq Applied Research Accelerator Facility (SARAF) - Overview, Research Programs and Future Plans

Abstract.The Soreq Applied Research Accelerator Facility (SARAF) is under construction in the Soreq Nuclear Research Center at Yavne, Israel. When completed at the beginning of the next decade, SARAF will be a user facility for basic and applied nuclear physics, based on a 40 MeV, 5 mA CW proton/deuteron superconducting linear accelerator. Phase I of SARAF (SARAF-I, 4 MeV, 2 mA CW protons, 5 MeV 1 mA CW deuterons) is already in operation, generating scientific results in several fields of interest. The main ongoing program at SARAF-I is the production of 30 keV neutrons and measurement of Maxwellian Averaged Cross Sections (MACS), important for the astrophysical s-process. The world leading Maxwellian epithermal neutron yield at SARAF-I (

Design of a new time-of-flight detector for isochronous mass spectrometry in the collector ring at FAIR

5 \times 10^{10}

Research Programs And Plans At The Soreq Applied Research Accelerator Facility - SARAF

5×1010 epithermal neutrons/s), generated by a novel Liquid-Lithium Target (LiLiT), enables improved precision of known MACSs, and new measurements of low-abundance and radioactive isotopes. Research plans for SARAF-II span several disciplines: precision studies of beyond-Standard-Model effects by trapping light exotic radioisotopes, such as 6He, 8Li and 18, 19, 23Ne, in unprecedented amounts (including meaningful studies already at SARAF-I); extended nuclear astrophysics research with higher energy neutrons, including generation and studies of exotic neutron-rich isotopes relevant to the rapid (r-) process; nuclear structure of exotic isotopes; high energy neutron cross sections for basic nuclear physics and material science research, including neutron induced radiation damage; neutron based imaging and therapy; and novel radiopharmaceuticals development and production. In this paper we present a technical overview of SARAF-I and II, including a description of the accelerator and its irradiation targets; a survey of existing research programs at SARAF-I; and the research potential at the completed facility (SARAF-II).

SHE Research with Rare-Isotope Beams, Challenges and Perspectives, and the New Generation of SHE Factories

The masses of exotic nuclei can be measured in ion storage rings by determination of their revolution time in the ring. At the current FRS-Experimental Storage Ring (ESR) facility one method to perform such measurements is the isochronous mass spectrometry (IMS). With the IMS masses of exotic nuclei with lifetimes as short as a few tens of can be measured. To determine these masses the revolution time of the ions in the isochronous ring is measured by a time-of-flight (TOF) detector. To achieve a high mass resolution the performance of the detector is crucial and has been improved significantly. The future Collector Ring (CR) at FAIR will be different compared to the current ESR not only in circumference but also in terms of beam dimensions and intensities. Based on extensive simulations, a new double detector system has been designed for improved IMS at the CR. It is adapted to the beam emittance of the ions in the CR and applies two TOF detectors so that the velocity can be measured in addition for every individual ion. This allows one to obtain correct mass values even for ions which are not perfectly isochronous. Improvements of almost a factor 2 for the timing accuracy with at least 95% detection efficiency will be achieved, even though the active area of the detector had to be increased by a factor of four to adapt to the larger emittance in the CR.

Thermaization and extraction of

The Soreq Applied Research Accelerator Facility (SARAF) is under construction at the Soreq Nuclear Research Center, Yavne, Israel. When completed at the beginning of the next decade, SARAF will be a user facility based on a 40 MeV, 5 mA CW proton/deuteron superconducting linear accelerator. Phase I of SARAF (4 MeV, 2 mA CW protons, 5 MeV 1 mA pulsed deuterons) is already in operation. By use of a novel liquid lithium jet target (LiLiT), we generated up to 5×10^10 epithermal neutrons/sec, mainly for nuclear astrophysics research of slow neutron capture processes (s-process). We present a survey of research programs and plans at the completed SARAF, which span several disciplines: Precision studies of beyond-Standard-Model effects by trapping light exotic isotopes, such as 6He, 8Li and Ne isotopes, in unprecedented amounts (including meaningful studies already at Phase I); extended nuclear astrophysics research with higher energy neutrons, including generation and studies of exotic neutron-rich isotopes relevant to the rapid (r-) process; high energy neutrons cross section measurements for basic nuclear physics and material science research, including neutron induced radiation damage; neutron based imaging and therapy; and novel radio-pharmaceuticals development and production.

^{238}

SHE research at GSI is strongly inspired by the ideas of Walter Greiner. He developed the theoretical concept of cold heavy-ion fusion, the use of magic nuclei for SHE production which was successful to create super heavy elements at GSI. Later the concept of magic nuclei for SHE production has been applied to hot fusion at JINR Dubna. A large region of super heavy elements extending even beyond element 114 has been discovered. The discovery of the spherical SHE is still waiting. New ideas to surpass the present limit at Z = 118 and to access the region of spherical SHE are needed. In this paper the perspectives for SHE production with rare-isotope beams will be discussed in the light of the new generation of SHE factories with intense beams. New experimental developments such as a setup for spectroscopic studies at the GSI SuperFRS and a next-generation in-flight separator with direct isotope identification will be addressed.

U projectile and fission fragments produced at 1000 MeV/u in the prototype cryogenic stopping cell for the LEB

M. P. Reiter1, A.-K. Rink1, F. Amjad2, S. Ayet 2, J. Bergmann 1, P. Dendooven 3, T. Dickel2, M. Diwisch1, J. Ebert1, A. Estrade2, F. Farinon2, H. Geissel 1,2, F. Greiner1, E. Haettner 2, F. Heisse2, C. Hornung1, C. Jesch1, N. Kalantar-Nayestanaki 3, R. Knoebel 2, J. Kurcewicz2, J. Lang1, W. Lippert1, I. Miskun2, I. Moore4, I. Mukha2, C. Nociforo2, M. Petrick1, M. Pfuetzner 2, S. Pietri2, W. R. Plaß1,2, I. Pohjalainen4, A. Prochazka 2, S. Purushothaman 2, M. Ranjan3, S. Rinta-Antila4, C. Scheidenberger 1,2, M. Takechi 2, Y. Tanaka2, H. Weick2, J. S. Winfield2, X. Xu2, and M. Yavor 5

Recent Technical Improvements for the Multiple-Reflection Time-of-Flight Mass Spectrometer at the FRS Ion Catcher

S. Ayet1,2, J. Ebert1, T. Dickel1,2, W. R. Plaß1,2, J. Bergmann1, H. Geissel1,2, E. Haettner2, C. Hornung1, C. Jesch1, J. Lang1, W. Lippert1, A. R. Pikhtelev3, S. Purushothaman2, M. P. Reiter1, A.-K. Rink1, C. Scheidenberger1,2, and M. I. Yavor4 1Justus-Liebig-Universität, Gießen, Germany; 2GSI, Darmstadt, Germany; 3Institute of Energy Problems of Chemical Physics of the Russian Academy of Science, Chernogolovka, Russia; 4Institute for Analytical Instrumentation of the Russian Academy of Sciences, St. Petersburg, Russia