[en] The National Institute for Nuclear Physics and High-Energy Physics NIKHEF is constructing AmPS, a pulse stretcher ring, as an extension to its existing electron linac facility. The project is primarily funded to produce continuous electron beams for nuclear physics experiments. The first beam for nuclear physics experiments is expected by mid 1992. AmPS is designed for energies between 300 and 1000 MeV and circulating currents up to 200 mA. Synchrotron radiation will be generated in each of the 32 bending magnets of the ring. At least two of its long straights are well suited to install either wavelength shifters (wigglers) and/or undulators. For nuclear physics AmPS will be operated for 2500 hours per year, an additional 2000 hours per year for dedicated SR use seems feasible. AmPS will provide SR beams from the VUV to the soft x-ray region; with appropriate insertion devices extension is possible up to the medium energy x-ray region. Its SR brilliance can be made fully competitive with new generation sources by adding 32 quadrupoles to its lattice

[en] The beam optical system of a Polarized Electron Source (PES) is described. The PES is used for nuclear physics experiments with internal gas targets on the MEA-AmPS acceleration facility at NIKHEF. The PES beam optical system consists of a 100 keV photoelectron gun, a 100 keV beam line, and a 400 keV post-accelerator. Both the electrostatic and the beam trajectory calculations in the gun have been performed with the SAM code. To calculate the beam envelope in the PES beam line the MAD code was used. The input for MAD was obtained from beam trajectory calculations in the gun, extrapolated for a beam with non-zero initial emittance. Results of the beam line performance test are given

[en] AmPS, an electron Pulse Stretcher/Storage Ring will start delivering nearly continuous electron beams of maximum 900 MeV in Spring 1992. The extracted beam (using the machine in Stretcher Mode) as well as the stored beam (in conjunction with an internal gas-jet target) will be used for nuclear physics purposes for about 2500 hours/year. For the remaining time of the year AmPS could be used as a dedicated Photon Source covering the spectrum from infrared up to soft X-rays. The synchrotron radiation properties of the actual machine are presented together with a design for a modified ring lattice. The modification only requires the addition of focusing elements to the actual machine so the characteristics in 'nuclear physics' mode are not affected. The new lattice will allow AmPS to be operated in a low-emittance mode (ε=4.5x10^-9 rad.m at 900 MeV) providing a SR brilliance from its bending magnets of 2x10¹⁴ photons/s/mrad²mm²/ 100 mA/0.1% BW. Further enhancement of the brilliance can be achieved by the implementation of multiple undulators. The ring can accommodate such insertion devices in one of its 32 m long straights. (author). 3 refs.; 3 figs.; 3 tabs

[en] AmPS, an electron Pulse Stretcher/Storage Ring will start delivering nearly continuous electron beams of maximum 900 MeV in Spring 1992. The extracted beam (using the machine in Stretcher Mode) as well as the stored beam (in conjunction with an internal gas-jet target) will be used for nuclear physics purposes for about 2500 hours/year. For the remaining time of the year AmPS could be used as a dedicated Photon Source covering the spectrum from infrared up to soft X-rays. The synchrotron radiation properties of the actual machine are presented together with a design for a modified ring lattice. Enhancement of the brilliance can be achieved by the implementation of multipole undulators. (author) 3 refs.; 3 figs.; 3 tabs

[en] AmPS has been built to enhance substantially the main specifications of the 1 % duty factor 550 MeV electron accelerator facility MEA. The maximum energy will be raised to 0.9 GeV while the duty factor increases from 1 % to approximately 100 %. To this purpose the ring AmPS was added to the facility. Simultaneously the linac was upgraded both in current and energy. Two modes of operation for the ring are implemented: a Pulse Stretcher mode with 3 turn injection creating an external beam, and a Storage Mode with multi turn injection for internal target physics. The commissioning of the ring started in April 1992. Within two months 10 % duty factor beams could be delivered for electron scattering experiments. Meanwhile the performance of the machine has been improved dramatically. The actual performance of the ring is presented and is compared with the initial design goals

[en] In order to increase the duty factor (d.f.) of the present 500 MeV electron lican from 2.5% to > 90%, it is proposed to add a pulse stretcher to the facility. By replacing 4 of the 12 existing 4 MW klystrons by 25 MW types, the injection energy will be increased to E = 700 MeV. A peak current of 40 mA will be injected during three turns with 365 pps. to yield an extracted beam current of 40 μA. The machine operates near a third order resonance. The chromaticity is non-zero. Extraction proceeds by changing the cavity frequency (2856 MHz); this will push the beam into the unstable region of the phase space. An energy compressor will reduce the momentum spread of the injected beam to absolute value of dp/p = 0.1%

No abstract available

[en] AmPS is a 900 MeV electron pulse stretcher and storage ring. Installation started early 1991 and commissioning is foreseen from Spring 1992 on. The rig contains 170 magnetic elements: dipoles, quadrupoles, sextupoles, steering magnets and magnetic septa. Apart from the 2 septum-magnet yokes all magnets are fully laminated. The magnets were designed with help of the Poisson code and by using conformal mapping methods. A prototype was made of each type of magnet, mainly to optimize the pole end chamfering. The required low harmonic content could be obtained by simple cuts of the pole ends. The steering magnets combine horizontal and vertical steering and have been designed for a low harmonic content as well. The injection septum with a septum thickness of 3 mm operates at a maximum current of 1,075 A. This septum is indirectly cooled. A novel electrical isolation technique is applied which also ensures a good thermal contact between the conductor and the yoke. The extraction septum is directly cooled. A computerized x-y-z field mapping device was developed as well as an inexpensive rotating coil measurement system. The design, both magnetically and mechanically, the constructional aspects and the measurement results of the magnets are presented together with a description of the measurement set-up

[en] This paper presents an initial design of a high luminosity (10³² cm^-2s^-1 e⁺ e^- collider which will cover the energy range of 400 to 800 MeV. The primary physics goal of such a machine would be the production of large numbers of φ(1020)-mesons, allowing detailed studies of a.o. CP violation in the K-bar K system. The intention is to use the existing 500 MeV electron-linac of NIKHEF to inject electrons and positrons into a two ring collider. One interaction region is foreseen in a dispersion free mini-beta insertion. On the basis of a specific lattice critical items will be discussed which may limit the performance of the storage ring

[en] The construction of a combined electron stretcher and storage ring operating at energies up to 0.9 GeV has recently started in Amsterdam. The ring will improve the specifications of the existing Medium Energy Accelerator (MEA) Facility of the Institute for Nuclear Physics and High Energy Physics Research (NIKHEF). This manuscript presents a summary of the vacuum system design of the ring. In order to achieve a 1 h beam life-time the vacuum pressure with a stored beam will have to be in the low 10^-8 mbar range. The major gas source is due to synchrotron radiation causing desorption from the stainless steel vacuum chamber walls. Because of the beam induced r.f. fields smoothness of the magnet vessels, monitors, beampipes and bellows is essential. Clearing electrodes are foreseen in order to avoid instabilities caused by ions produced by the beam in the residual gas. (author)