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After termination of the LEAR facility in 1996 and the restriction of the CERN antiproton program to Trap experiments, stored antiprotons at low and medium energies are no longer available for experiments. FAIR at GSI (Darmstadt) will provide intense stored antiproton beams in less than a decade from now. This has renewed the interest in polarized antiprotons originally proposed for LEAR. In August 2007, an International Workshop was organized at the Cockcroft Institute (Daresbury) and methods to polarize stored antiprotons were discussed. In June 2008, a Heraeus Seminar at the Physikzentrum in Bad Honnef dealing with the same subject took place. The results of these workshops will be presented with some historical remarks and an account of the recent developments. [ABSTRACT FROM AUTHOR]

This paper summarizes the attempts and ideas for generating polarized antiproton beams. Such beams are needed for the study of the—largely unknown—spin dependence of nucleon-antinucleon interaction. Emphasis is on spin dependent attenuation of antiprotons on a polarized hydrogen target as the only experimentally tested method. [ABSTRACT FROM AUTHOR]

The talks related to gas targets and ion sources are summarized. The main areas of interest were hydrogen and deuterium gas targets for storage rings, fed by atomic beam sources, and pulsed ion sources for injection into synchrotrons, both for the hydrogen isotopes and for fully stripped 3He. Impressive progress has been achieved in the last few years. [ABSTRACT FROM AUTHOR]

Proposed in 1990 the HERMES experiment aimed at the measurement of spin-dependent observables in deep-inelastic scattering of electrons on few-nucleon targets. It relied on the availability of polarized stored electrons and on gas targets of sufficient density and polarization. Data were taken from 1995 to 2007. This paper describes how these key techniques were developed and applied during the run. [ABSTRACT FROM AUTHOR]

The design and operation of the polarized hydrogen and deuterium gas target internal to the HERA 27.5 GeV polarized electron ring is described. The target has been employed to measure the spin structure of the nucleon, using beams of electrons and positrons, both polarized and unpolarized. The various components of the target system will be described and the operation summarized. The target was removed in November 2005, after 10 years of successful running. It will be utilized in preparation of the PAX experiment at FAIR (Darmstadt) for spin filtering studies of protons and antiprotons. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The state of the art of polarized gas targets for storage rings is reviewed. The storage cell technique is inevitable for producing densities with sufficient luminosity for electron scattering experiments. Different sources of polarized atoms for jets and storage cell targets are compared. Remarkable progress has been achieved over the last 15 years, which has led to a vast amount of experimental results with high statistics and good systematic precision. For hydrogen or deuterium gas targets based on atomic beam sources and cold storage cells an areal density of 1014 atoms/cm2 with high polarization has been achieved. For a next generation experiment this figure could be considerably enhanced. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

The International Workshop PST99, devoted to Rudolf Fleischmann, was conducted at Erlangen from September 29 to October 2, 1999, and attended by about 120 scientists from nine countries. The program consisted of three parallel sessions on polarized ion sources and gas targets, polarized electron sources and polarized solid targets. In addition, the plenary sessions included reports on spin experiments and applications, and summary talks of all three topics. The workshop provided an overview of existing sources and targets at operating facilities and highlighted the developments necessary for a new generation of spin experiments. [ABSTRACT FROM AUTHOR]