| Paper | Title | Page |
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| MOPC110 | Commissioning of the Heidelberg Cryogenic Trap for Fast Ion Beams (CTF) | 319 |
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| At the MPI für Kernphysik, a cryogenic electrostatic heavy-ion storage ring (CSR) is being developed. As a cryogenic test facility (CTF), an electrostatic ion beam trap is nearing completion. It will store ions between two electrostatic mirrors, confining them radially by two einzel lenses set apart by 30 cm. This linear, open design leaves room for testing beam diagnostic devices developed for the CSR, e.g. split ring electrodes and a residual gas monitor. As for the CSR, parts of the vacuum system will be brought in direct contact with superfluid helium, to achieve an operating temperature of 2-10 K. Under these conditions, we expect residual gas pressures in the 10-15 mbar range, and storage times on the order of minutes for light molecular ions. We will present first results from the commissioning of the CTF, especially the temperatures and residual gas pressures reached in the trap, as well as experiences with the position stability of the mechanical suspension of the trap electrodes in cryogenic operation. | ||
| MOPC137 | The Cryogenic Storage Ring Project at Heidelberg | 394 |
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| At the Max-Planck-Institut für Kernphysik in Heidelberg a next generation electrostatic storage ring at cryogenic temperatures is under development. The main perspective of this unique cryogenic storage ring (CSR) is the research on ions, molecules and clusters up to bio molecules in the energy range of 20 keV -300 keV at low temperatures down to 2 Kelvin. The achievement of this low temperature for all material walls seen by the ions in the storage ring not only causes a strong reduction of black body radiation incident onto the stored particles, but also acts as a large cryopump, expected to achieve a vacuum of better than 1·10-15 mbar (corresponding to 1·10-13 mbar room temperature äquivalent). The low temperature and the extreme low vacuum will allow novel experiments to be performed, such as rotational and vibrational state control of molecular ions and their interaction with ultra-low energy electrons and laser radiation. A 20 W at 2 K refrigerator was designed and successfully commissioned. A connection with the fully assembled cryogenic prototype ion trap is under way. In this paper the concept and the status of the cryogenic storage ring will be presented. | ||
| TUPC097 | Beam Diagnostics for the Prototype of the Cryogenic Storage Ring CSR | 1287 |
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| The Cryogenic Storage Ring CSR at the MPI-K Heidelberg will be a 35m circumference, electrostatic ring, which is mainly dedicated to Molecular- and Atomic Physics experiments. To reach the low pressures (10-15 mbar), which are necessary to achieve the required long liftetimes of the stored ions, the complete ring has to be operated at a temperature below 4K (2K in sections), which means, that it will be installed inside a large cryostat. To prove the novel cryogenics and vacuum concept of the CSR, we have built up a prototype, which is basically a segment of the CSR, housing an electrostatic ion trap. The ion trap is in the first instance used for vacuum measurements and equipment tests in the XHV range, in a later stage, it shall be an experimental facility of its own. Test operation of the Prototype is currently starting. Since the boundary conditions in the CSR are highly demanding for the beam diagnostics system, we have to perform some tests of the CSR diagnostics devices in our Prototype setup. The Poster will describe these devices and present first experimental results. | ||
| TUPP093 | Crystalline Beam Simulations | 1747 |
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| A new program code was elaborated for the simulation of crystalline beams on the S-LSR storage ring (Kyoto Univ., Japan) under action of the cooling system. For the investigation of ordered proton beams, which recently were observed in first time on S-LSR, a special molecular dynamics technique was used. This article presents results of the numerical simulation and comparison with experimental data. | ||
| THPP050 | Recent Status of Laser Cooling for Mg Realized at S-LSR | 3476 |
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At an ion storage and cooler ring, S-LSR, a laser cooling has been applied to the 40 keV 24Mg+ ion beam guiding a laser with the wave length of 280nm parallel to the ion beam together with the deceleration by an induction voltage. Up to now, the longitudinal temperature has been cooled down to 3.6 Kelvin for the ion number of 3x104 although the transverse one still remains around 500 Kelvin. The longitudinal temperature is limited by the heat transfer from the transverse degree of freedom through intra-beam scattering, which becomes stronger according to increase of ion number. It is found that the equilibrium longitudinal temperature is linearly coupled with the transverse one* for our experimental condition up to now. In the present paper, recent experimental data will be presented together with the procedure of beam diagnosis with the use of optical methods using a spontaneous emission of the Mg ions. Possible approach to realize the resonant coupling through synchro-betatron coupling** is also to be presented.
* M. Tanabe et al., To be published in Applied Physics Express (APEX). |
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| THPP053 | One-dimensional Ordering of Protons by the Electron Cooling | 3485 |
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| One of the main subjects of the compact cooler ring, S-LSR at Kyoto University is the physics of the ultra cold ion beam, such as the ordered beam and the crystalline beam, using the electron and laser cooling. The one-dimensional ordering of protons has been studied at S-LSR, while the ordering the highly charged heavy ions has been found at ESR and CRYRING. Abrupt jumps in the momentum spread and the Schottky noise power have been observed for protons at a particle number of around 2000. The beam temperature was 0.17 meV and 1 meV in the longitudinal and transverse directions at the transition, respectively. The normalized transition temperature of protons is close to those of heavy ions at ESR. The lowest longitudinal beam temperature below the transition was 0.3 K. It is close to the longitudinal electron temperature. The dependence of the ordering conditions on the betatron tune and the transverse beam temperature have been also studied. These results will be presented in the presentation. |