Search

Abstract: The international Facility for Antiproton and Ion Research (FAIR) at the GSI Helmholtz Centre for Heavy Ion Research in Germany is composed of a chain of accelerators and storage rings that will, amongst others, produce, store and slow down antiprotons with unprecedented beam characteristics. One of these rings, the Ultra-low energy electrostatic Storage Ring (USR), will provide cooled beams of antiprotons at energies as low as 20keV with a small momentum spread of ∼10−4 and an emittance in the order of 1π mmmrad. Crossed-beam atomic physics experiment that will allow, for the first time, to investigate into the collision dynamics of antiprotons with different target gases on the level of differential cross sections, require very short antiproton pulses of 1–2ns duration. An “ultra-short pulse” operation mode was developed to enable these novel experiments. This paper describes two alternative schemes that were developed in the QUASAR Group and summarizes the changes required to enable the USR to operate in this mode. [ABSTRACT FROM AUTHOR]

Abstract: An electrostatic storage ring for low-energy ions with a design energy of 50keV is presently being set up at the Institut für Kernphysik der Johann Wolfgang Goethe-Universität Frankfurt am Main, Germany (IKF). This new device will provide a basis for new experiments on the dynamics of ionic and molecular collisions, as well as for high precision and time resolved laser spectroscopy. In this article, the design parameters of this instrument are reported. [Copyright &y& Elsevier]

The Antiproton Decelerator and cooling ring (AD) provides dense and cold beams of antiprotons to low energy experiments for the study of basic properties of antiprotons and antihydrogen. It combines stochastic cooling (at 3.5 and 2 GeV/c) with electron cooling at 0.3 and 0.1 GeV/c. In 2002 the AD gave beam during more than 1900 h to its three experiments (ASACUSA, ATHENA and ATRAP) with beam properties meeting, and often exceeding design specification. Stochastic cooling with cool-down times of 18 s works as aimed for in the design. Electron cooling using the “old LEAR cooler” reaches the very small equilibrium emittances required but still takes more time (12 s instead of 6 s anticipated in the 1996 design). However the increase in cycle length is made up for by the higher deceleration efficiency. ASACUSA has very successfully continued the program of antiprotonic helium 3 spectroscopy and ATHENA and ATRAP have reported last autumn the synthesis of copious numbers of cold antihydrogen atoms. [Copyright &y& Elsevier]