Annual report / Institut für Kernphysik and COSY Research 1999
Annual report / Institut für Kernphysik and COSY Research 1999
This report lists the 1999 activities of the IKP jointly performed with our partners of CANU and colleagues from other universities and international laboratories as well as experiments that IKP scientists have carried out at external research facilities. The focus of the accelerator development was...
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Personal Name(s): | Baur, G. (Editor) |
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Filges, D. (Editor) / Kilian, Kurt (Editor) / Maier, Rudolf (Editor) / Rossen, P. von (Editor) / Seyfarth, Hellmut (Editor) / Sistemich, K. (Editor) / Speth, J. (Editor) / Ströher, H. (Editor) / Freiesleben, H. (Editor) | |
Contributing Institute: |
Publikationen vor 2000; PRE-2000; Retrocat |
Imprint: |
Jülich
Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag
2000
|
Physical Description: |
249 p. |
Document Type: |
Report Book |
Research Program: |
Addenda |
Series Title: |
Berichte des Forschungszentrums Jülich
3744 |
Link: |
OpenAccess OpenAccess |
Publikationsportal JuSER |
This report lists the 1999 activities of the IKP jointly performed with our partners of CANU and colleagues from other universities and international laboratories as well as experiments that IKP scientists have carried out at external research facilities. The focus of the accelerator development was on polarized beams. With the beginning of the year, TOF was the first external experiment to be run with polarized protons. During the course of the year the number of polarized protons accelerated to the flat-top was raised to2 $\cdot$ 10$^{9}$, gaining one order of magnitude in intensity compared to the previous year. A new tuning technique has been developed to more efficiently reduce the influence of the depolarizing resonances. lt allowed to substantially improve the preservation of polarization during acceleration. At this point, we gratefully acknowledge the strong support by the EDDA collaboration whose detector was the key for this accomplishment. External proton beams with a pulse length of 1 $\mu$s were developed to provide the basis for target-moderator studies by the JESSICA collaboration which will investigate the underlying physics to optimize future neutron spallation sources. To relieve the situation with regard to the tight floor space a concept was worked out for a new external beam line to the so called East Hall of the cyclotron building. This half could harbor besides others the planned TETHYS experiment. The basic research in connection with the European Spallation Source was further advanced. The NESSI collaboration completed a whole series of experiments concerning the target geometry and target material as well as neutron and charged particle production cross sections and multiplicities. In parallel investigations for a superconducting alternative to a pulsedproton linac for the spallation source were performed. A superconducting fest cavity has been prepared by the industry for delivery and first tests at CERN verified the compliance with the original main specifications. The TOF-collaboration investigated, among other things, the bremsstrahlung in proton-proton collisions using the first external polarized proton beam at a momentum of 800 MeV/c. The TOF-detector acted in this measurement simultaneously as a precise polarimeter due to its symmetrical structure and large acceptance. The $\eta$-production was studied at excess energies of 15 and 40 MeV. A clear signal for the $\eta$-meson was extracted in a prelirninary analysis. The components for the TOF-calorimeter, that will extend the capabilities of this detector, were completed. The study of the p d $\rightarrow$ $^{3}$He $\eta$ reaction by GEM revealed an unusual forward/backward peaking of the angular distribution in comparison to the threshold data which demands further polarization measurements for clarification. The measured cross section data of the GEM collaboration for the reaction p d $\rightarrow$ $^{3}$He $\pi$° bridge the gap between the near threshold data and those in the $\Delta$-resonance region, but are not theoretically understood as yet.C0SY-11 continued its successful investigation of open and hidden strangeness by studying single meson, $K^{+}K^{-}$, and $K^{+}$-hyperon production at their respective thresholds. Measurements for the production of $\eta$, $\eta'$ with a deuterium target have been started. [...] |