Dedicated Synchrotron Radiation Source Research Articles

Electrons, photons and ions at Daresbury

Daresbury Laboratory has now been in existence for over 20 years. Early high energy physics work utilized electron and photon beams from the 5 GeV electron synchrotron NINA and use was made of the synchrotron radiation emitted by the circulating electron beam for a range of studies. Following the closure of NINA, activities at the Laboratory centred on a 2 GeV electron storage ring used as a dedicated synchrotron radiation source and a 20 MV tandem Van de Graaff accelerator which provides a wide range of accelerated ions for nuclear structure studies. Both machines have been in regular and effective use for several years and have established international reputations in their respective fields.

The European Synchrotron Radiation Facility

A new design study for the European Synchrotron Radiation Facility (ESRF) has been carried out in the past year by the European Synchrotron Radiation Project Group. The aim was to extend the work done in 1979 and 1982, under the auspices of the European Science Foundation, towards a very high brilliance, hard X-ray machine. The guidelines for the design of a dedicated Synchrotron Radiation Source in the X-ray region were laid out in 1982 by the ESRF study group and confirmed at a ESRP workshop in 1983. It was concluded then that a low emittance storage ring with a large number of straight sections for wigglers and undulators, and the capability for also providing bending magnet sources in the 1 A wavelength region should be built. The possibility of deciding on the number of a given type of device at a late stage in the project, or indeed at any time during operation, was deemed to be an important design feature.

Absolute measurement of undulator radiation in the extreme ultraviolet

The spectral brightness of undulator radiation emitted by the model PMU-1 incorporated in the SOR-RING, the dedicated synchrotron radiation source in Tokyo, has been studied in the extreme ultraviolet region from 21.6 to 72.9 eV as a function of the electron energy γ, the field parameter K, and the angle of observation ϴ in the absolute scale. A series of measurements covering the first and the second harmonic component of undulator radiation was compared with the fundamental formula λ n= λ 0 2nγ 2 ( 1+K 2 2 +γϴ 2 and the effects of finite emittance were studied. The brightness at the first peak was smaller than the theoretical value, while an enhanced second harmonic component was observed.

Optimization of parameters of a dedicated synchrotron radiation source for technology

The problems of optimizing the parameters of a storage ring used as a source of synchrotron radiation (SR) for a multiplicity of sub-micron technology applications are considered. The storage ring lattice optimized for the minimum emittance of the electron beam provides for installation of undulators and wigglers to generate the high-power beams of ultra-violet (λ = 1200−2000 A ̊ ) , soft X-ray (λ = 40−10 A ̊ ) and X-ray (λ = 4−2 A ̊ ) radiation. A number of design features are proposed, viz magnets with three different levels of magnetic field, a SR beam sweep for wigglers and undulators, quadrupole lenses made of two pieces, etc., which are optimal in the storage ring used as a dedicated SR source for technology.

Observation of Undulator Radiation. I. Operation Studies and Visual Observation

A 19-pole permanent magnet undulator has been tested by inserting it into a straight section from outside the vacuum chamber of the SOR-RING, a dedicated synchrotron radiation source operated between 0.2 and 0.38 GeV. It was confirmed that the undulator field did not seriously disturb stable operation by observing the shift of the closed orbit and the shift of the betatron numbers. Some results of visual observation of the radiation are presented. The polarization character was studied on the rainbow circle with a polarizer and some theoretical results by Kitamura were confirmed. It was found that the interfering synchrotron radiations along the straight section of the storage ring make a series of rainbows even without the undulator field.

Status of the SOR-RING and the experimental program for 1979/80

General features and a brief operational history of the SOR-RING, a 400 MeV dedicated synchrotron radiation source constructed in 1974 in Tokyo, and the status as of fall 1979 are presented. The experimental program to be performed during the fiscal year 1979/1980 is summarized.

Lattice of Photon Factory Storage Ring

The lattice of the storage ring of KEK Photon Factory (dedicated synchrotron radiation source) is described. The design principle is the availability of straight sections for the wiggler and the flexibility of optics. The final design is checked with respect to the disturbance of beam dynamics by momentum error and magnetic imperfections.

The SRS: Progress Report on the Dedicated Synchrotron Radiation Source at Daresbury; and Operation of a 600 MeV Booster

Design of the 2 GeV Storage Ring is virtually complete and construction will be finished in April 1980. The injector, a 600 MeV 10 Hz synchrotron, has been commissioned and its performance is reported.

Progress report on the 2GeV synchrotron radiation source (SRS) at Daresbury

In May 1975 the proposal by the Science Research Council to construct a 2GeV electron storage ring at Daresbury Laboratory was approved. The storage ring is to be a dedicated Synchrotron Radiation Source (SRS) devoted to experiments in all fields of science using ultraviolet and X-radiation. Construction has now started and completion is planned for late 1979. The new source will be installed in existing buildings built to house the 5 GeV electron synchrotron NINA, which ceased operation on 1st April 1977 and is now being removed. The field in the normal bending magnets is 1.2 T, and the initial objective is a circulating beam current of 500 mA. It is planned to raise this later to 1 A. The storage ring will provide intense fluxes of photons up to about 20 keV from normal ports and up to 100 keV from 5 T superconducting transverse 3-pole wiggler magnets, of which two are planned. Up to 12 beam ports are envisaged, of which six to eight should be in operation by 1983. Detailed plans for the first six ports are now being prepared. Beam lines up to 80 m long will be available for X-ray topography experiments. The VUV lines are being designed to give best possible access for experimenters, free from hazard from high energy bremsstrahlung. Injection is from a 600 MeV synchrotron, itself fed by a 15 MeV linear accelerator. All major components of the injection system have beem ordered and completion is planned for May 1978. Detail design of the storage ring is now in progress; prototypes are being tested of the 500 MHz rf cavity, a special multipole magnet, the dipole magnet vacuum chamber (with beam port and backward tangent recess) and other components. Development of the control system is well advanced and it will be used for commissioning the injection system. The paper briefly describes the source and outlines the plans for the initial beam lines. It reports on the progress of construction and development work.

Fast Extraction of Electrons from INS Synchrotron for Injection to SOR-RING

A fast extraction system has been developed, which is used for taking out electron beams of 300 MeV from the 1.3 GeV INS synchrotron and injecting them into the SOR-RING, or a 300 MeV electron storage ring used as a dedicated synchrotron radiation source. The system consists of a fast kicker magnet of lumped-circuit type fed by a pulse-forming-network, and a septum magnet. The fast kicker magnet is excited through a spark gap of triggertron type with average time jitter of switching within ±5 ns for 5×105 operations in free flowing dry nitrogen gas. A pulsed magnetic field of 410 G with a risetime of 50 ns and a duration of 80 ns was obtained when the exciting current was 490 A. The extraction efficiency was estimated to be about 60%.