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A description is given of the upgraded photon tagging facility at the MAX IV Laboratory. Two magnetic spectrometers are used to momentum analyze post-bremsstrahlung electrons. The tagged photon range extends from 10 to 180 MeV with an energy resolution of about 300 keV. The system has been operated at rates up to 4×106 photons s-1 MeV −1. Different diagnostic tools are described as well as the experimental program.

One of the primary goals of the 700MeV MAX III synchrotron radiation source is to test and gain experience with new magnet and accelerator technology. Each magnet cell is machined out of two solid iron blocks that are then sandwiched together after coil and quadrupole installation. The MAX III ring makes extensive use of combined function magnets to obtain a compact lattice. In order to obtain flexibility in machine tuning pole face current strips are used in the main dipoles, which also contain the horizontally defocusing gradients. Commissioning finished in 2007 and MAX III is now going into user operation. Over the last year, MAX III has been characterized in order to both obtain calibrated models for operation purposes as well as evaluating the magnet technology. The characterization results will be described in this paper. (Less)

A method of realigning the quadrupole magnets in storage rings to achieve minimum dipole corrector strengths is described. The corrector strengths after realignment are mainly determined by Beam Position Monitor offsets relative to the quadrupole magnets they have been calibrated against and the extent to which magnet dipole errors stay constant during the realignment. The accuracy to which quadrupole misalignments can be determined is mainly limited by dipole errors not originating from quadrupole displacements and the accuracy to which BPM offsets can be determined. After realigning a ring by the described method, any subsequent realignment with the aim to compensate for long-term magnet movements can be performed with greater accuracy. The method was applied at the MAX III storage ring and the magnet positions were then measured in the conventional way with a laser tracker. The difference between the two methods is discussed. Finally, the realignment result was compared with simulated results for two different MAX III test cases.

Two examples of low-emittance light-source lattices are discussed. Both use similar building blocks consisting of 7-bend achromats. The small emittances generated by these lattices are further reduced by the introduction of insertion devices (IDs), resulting in beam emittance values ranging from 0.2 to 0.9 nm rad, depending on the number of achromats chosen. The two examples discussed here are rings with 12 and 20 achromats. The performances of any intermediate number of achromats can easily be estimated. A higher number of achromats of this type seems to result in an uncomfortably small dynamic aperture. The Touschek losses and Intra Beam Scattering (IBS) effect are calculated together with some means to reduce their impact. To calculate this impact, certain technical solutions are assumed, which are described. Other technical solutions could naturally be chosen. The impact of emittance on brilliance is also discussed and the brilliance curves for the two cases are presented and compared with the zero-emittance case ("ultimate source"). (C) 2008 Elsevier B.V. All rights reserved. (Less)

In an earlier paper we reported on a new septum magnet design with a magnetic flux filter [1]. Now the first septum magnet is in operation as an injection septum magnet for the MAX I storage ring. We describe the actual mechanical construction and the field measurements of the new magnets. The fine structure of the septum nose needed several trials in the construction until we found the final solution. The measured residual stray fields in the ring tube are even smaller than was expected from the model calculations.

The MAX-IV storage rings are being studied at MAX-Lab. In this paper, we present the magnetic measurements of the soft bending magnet prototype. The magnet is introduced in the matching section of the 3 GeV storage ring lattice [Tarawneh, Proceedings of European Particle Accelerator Conference, July 2004, Lucerne, Switzerland] mainly to reduce the power of the synchrotron radiation hitting the upstream superconducting insertion devices.

At MAX-LAB the next synchrotron light source MAX-IV is currently studied (Proceedings of the seventh European Particle Accelerator Conference, EPAC 02, Paris, France, 2002). In this paper, we present a possible lattice with horizontal emittance of 1.2 nm rad at an energy of 3 GeV. The possibilities to realise the main magnetic system with high gradient integrated magnets are studied with 2D and 3D magnetic field programs. The dynamic properties for the lattice are also studied and some higher order corrections are discussed.

We are currently investigating a device capable of generating continuous, coherent radiation down in the Angstrom region in sub-ps pulses in a relatively compact set-up. By placing a cascaded optical klystron (OK) in the return path of a 3 GeV Race Track Microtron operating in Energy Recovery mode Harmonic Generation can be performed in several stages in parallel. A four stage OK can generate Angstrom radiation from a 266 nm seed. The demands on the electron optics are severe, but the requirements on the electron beam are not extreme. The layout of a possible facility is presented and the basic concepts are discussed below. (C) 2003 Elsevier Science B.V. All rights reserved.

A new 250 MeV energy electron pulse-stretcher mode is designed where the MAX I ring is injected from a new linac system (Nucl. Instr. and Meth. A 490 (2002) 592). For the new slow extraction, we will try to achieve a lower emittance in the extraction plane by using a different extraction method. Injection and slow extraction are simulated.

New magnetic DC septa are designed for the upgraded Max I and the new Max III storage rings, respectively. The new septum is made magnetically symmetric with a magnetic flux filter in the septum nose. The residual stray fields in the ring tube become almost linear and the usually strong stray fields close to the septum sheet are eliminated. If necessary a final correction of the linear part could be done in the injection straight.

A 1.5 GeV third generation storage ring optimised for the VUV and soft X-ray spectral region is currently being built at MAX-lab. The magnet lattice, ring architecture and production choices are optimised to fit within rather tight boundary conditions without sacrificing performance. In this paper, the magnet lattice, light characteristics, injection and technical solutions for the ring are presented.

The accelerator system MAX has now for a couple of years produced a stretched electron beam of up to 95 MeV energy in stretcher mode and stored currents around 250 mA at 550 MeV energy in storage mode. This paper gives the current status of the pulse stretcher. Changes of hardware and operation conditions, compared to the design, are given together with experiences gained.