The design of a planar pure permanent magnet undulator is presented. The design requirements and mechanical difficulties for holding, positioning, and driving the magnetic arrays are explored. The structural, thermal, and electrical considerations that influenced the design are then analyzed. And finally detailed magnetic measurements are presented.

The NSLS X28C white‐light beamline is being outfitted with a focusing mirror in order to increase, as well as control, the x‐ray intensity at the sample position. The new mirror is a 50 mm × 100 mm × 1100 mm single crystal silicon cylindrical 43.1mm radius substrate bendable to a toroid from infinite to 1200 m radius. The unique feature of this mirror system is the dual use of Indalloy 51 as both a mechanism for heat transfer and a buoyant support to negate the effects of gravity. The benefit of the liquid metal support is the ability to correct for minor slope errors that take the form of a parabola. A bobber mechanism is employed to displace the fluid under the mirror +/− 1.5 mm. This allows RMS slope error correction on the order of 2 urad. The unique mounting of the mirror ensures the contributions to slope error from errant mechanical stresses due to machining tolerances are virtually non‐existent. After correction, the surface figure error (measured minus ideal) is <= 0.5 urad rms.

Advanced Design Consulting developed control software entitled IDcontrol for its state-of-the-art Apple II insertion devices (ID). These IDs feature 8 controllable axes: four servo motors control the gap and taper of two main girders, and four servo motors control the photon polarization-state by manipulating four sub-girders. IDcontrol simultaneously positions all 8 axes with high precision in real-time using 0.1 micron linear encoders attached directly to the girders and sub-girders. Helical and Inclined Plane phase modes are supported with automated mode switching. Magnetic-field-correction- coil current and girder taper are adjustable as functions of gap, phase, and phase mode. IDcontrol continuously monitors redundant encoder velocity and position data for maximal reliability, encoder failure detection, and damage prevention. Combined with ADC's Graphical User Interface (GUI) entitled IDgui, IDcontrol manipulates the ID, provides user notification and automated recovery from errors, management of correction data, and isometric visualization of the ID's girders. The functionality of both IDcontrol and IDgui has been demonstrated at MAX lab and the results will be discussed.

This end station has been specially engineered to solve the problem of the limited optical access typically associated with magnetic fields and synchrotron radiation measurement stations. An octupole magnet provides a fully variable direction vector field. A cryogenically cooled manipulation transfer system is provides the necessary flexibility to address a wide variety of magnetic samples. The whole system is ultra high vacuum compatible with a base pressure of 5 x 10(-10) mbar. The eight water-cooled magnets, spaced equidistantly over the surface of a sphere, allow the application of the field in any direction. These high current magnets generate a field in the area of the sample of I T. A photodiode detector travels along a +/- 90 [deg] are perpendicular to the beam axis. This motion, coupled with the entire system rotation of +/- 90 [deg] and incoming light polarization allows for the diode to be placed anywhere on a hemisphere perpendicular to the beam for any light polarization. The system also has provisions for cooling the sample with LHe and sample positioning in X, Y, Z, and rotation about the Z axis with micron resolution.

The existing 15-year-old hybrid wiggler at the NSLS has been replaced by a state-of-the-art, cryo-ready in-vacuum undulator optimized for a dedicated macromolecular crystallography program. The device is a 1m long, 18mm period, hybrid PM-type with a minimum operating gap of 5.6mm, and has provision for cryo-cooling to 150K. Unlike the original SPring-8 cryo-PM undulator proposal, we use a new high-remanence, high-temperature grade of NdFeB (NEOMAX 42AH with Br=1.3T and Hcj=24 We) that can be baked to 100 degrees C to be UHV-ready in case of cooling system failure. A novel optical gap measurement system using a LED-based product ensures gap accuracy of 2 micro meter. A friction stir welding technique is used for the first time in an accelerator UHV device to minimize stress and deformation of the magnet arrays due to temperature gradients. This paper describes design issues of the device and other considerations such as magnetic measurement at low temperature.

This paper summarizes the final magnetic measurement for a hybrid wiggler shown in Figure I installed at the Australian Synchrotron Project (ASP). This device uses an anti-symmetric, hybrid design with a period of 100 mm and 40 full-strength Vanadium-Permendur poles surrounded by Neodynium-Iron-Boron magnets (see table 1 for wiggler specification). It is designed to operate at two gaps with critical energies of 11.4 (14mm) and 9.6 keV (18.16mm) and to have a maximum gap with the field strength B-y <= 50 G. The wiggler's drive mechanism is capable of moving from minimum to maximum gap in 96 seconds. Table 2 shows minimum gap fourier analysis.End terminations are designed to maintain the electron trajectory on-axis. The straightness of the electron orbit is controlled by moving the poles vertically and horizontally. The integrated multipoles are controlled over the interval vertical bar x vertical bar < 25 mm and all gap sizes by moving the side magnets, installing correction magnets at the wiggler entrance and exit and using correction coils. All adjustments have been made using threaded fasteners. No shims have been used.