The cryogenic storage ring CSR

Journal Article · Wed Jun 15 00:00:00 EDT 2016 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4953888· OSTI ID:22597965

Hahn, R. von; Becker, A.; Berg, F.; Blaum, K.; Fadil, H.; Fellenberger, F.; Froese, M.; George, S.; Göck, J.; Grieser, M.; Grussie, F.; Guerin, E. A.; Herwig, P.; Karthein, J.; Krantz, C.; Kreckel, H.; Lange, M.; Laux, F.; Lohmann, S.; Menk, S. ^[1] ; others, and

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1. Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany)

An electrostatic cryogenic storage ring, CSR, for beams of anions and cations with up to 300 keV kinetic energy per unit charge has been designed, constructed, and put into operation. With a circumference of 35 m, the ion-beam vacuum chambers and all beam optics are in a cryostat and cooled by a closed-cycle liquid helium system. At temperatures as low as (5.5 ± 1) K inside the ring, storage time constants of several minutes up to almost an hour were observed for atomic and molecular, anion and cation beams at an energy of 60 keV. The ion-beam intensity, energy-dependent closed-orbit shifts (dispersion), and the focusing properties of the machine were studied by a system of capacitive pickups. The Schottky-noise spectrum of the stored ions revealed a broadening of the momentum distribution on a time scale of 1000 s. Photodetachment of stored anions was used in the beam lifetime measurements. The detachment rate by anion collisions with residual-gas molecules was found to be extremely low. A residual-gas density below 140 cm{sup −3} is derived, equivalent to a room-temperature pressure below 10{sup −14} mbar. Fast atomic, molecular, and cluster ion beams stored for long periods of time in a cryogenic environment will allow experiments on collision- and radiation-induced fragmentation processes of ions in known internal quantum states with merged and crossed photon and particle beams.

• OSTI ID: 22597965
• Journal Information: Review of Scientific Instruments, Vol. 87, Issue 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANIONS
BEAM OPTICS
CATIONS
CRYOSTATS
DENSITY
ENERGY DEPENDENCE
FRAGMENTATION
HELIUM
ION BEAMS
ION PAIRS
KEV RANGE 100-1000
KEV RANGE 10-100
KINETIC ENERGY
LIQUIDS
PARTICLE BEAMS
PHOTONS
QUANTUM STATES
SPECTRA
STORAGE RINGS
TEMPERATURE RANGE 0273-0400 K