Polarized H[sup −] and D[sup −] Beams at COSY∕Jülich

Abstract

A polarized atomic-beam target for COSY-Jülich AIP Conf.Abstract. By advancing the components of the polarized negative ion source the number of polarized particles for injection into the cyclotron injector of the cooler synchrotron COSY at the IKP of the Forschungszentrum Jillich has been increased, since 2000, by a factor of three to 5,5x10^^ ff ions, delivered in a 20 milUseconds pulse with a repetition rate of 2 seconds. This report sums up briefly the characteristics of the ion source in its present mode of operation and describes the achievements towards higher beam intensities as well as for providing polarized H" and D" beams with high reUabUity.

Polarized Ion Sources

“…This exceeds the original design value of 30 µA. It was the result of the optimization of all source components [12].…”

Review of polarized ion sources (invited)

“…It was the result of the optimization of all source components. 11 A breakthrough decision was to develop a pulsed cesium beam matched to the short injection period of up to 20 ms for COSY, thus virtually eliminating the severe sputtering damage that had been an obstruction for reliable operation. Beam diagnostics, like beam scanner, faraday cups, and viewer, for the cesium beam were added to successfully shape the transverse phase space for optimal overlap with the atomic hydrogen or deuterium beam.…”

Measurement of polarization observables of the associated strangeness production in proton proton interactions

“…Both runs are analyzed together by assuming a weighted mean beam polarization of (79.3 ˘2.0)%. For the data taking the direction of the beam polarization was changed by switching the polarization in the H ´ion source [14] with every spill, which has a typical length of 100 s.…”