Utility load management programs, including direct load control and interruptible load programs, constitute a large installed base of controllable loads that are employed by utilities as system reliability resources. In response to energy supply shortfalls expected during the summer of 2001, the California Public Utilities Commission in spring 2001 authorized new utility load management programs as well as revisions to existing programs. This report provides an independent review of the designs of these new programs for a large utility (Southern California Edison) and suggests possible improvements to enhance the “price responsiveness” of the customer actions influenced by these programs. The report also proposes a new program to elicit a mass-market demand response to utility price signals.

An elliptically polarizing undulator (EPU) has been assembled, tested, and installed in the Advanced Light Source (ALS) storage ring. It is a 2 m long pure permanent magnet device with a 5.0 cm period capable of providing polarized radiation of any ellipticity. This paper reports on the program of magnetic measurements and field tuning, and final magnetic and drive system performance. A summary of measurement results, calculated radiation spectral performance, and a description of the magnetic shimming procedure used for field tuning are included

As first pointed out by K.-J. Kim (KIM K.-J.,Phys. Rev. Lett.,76 (1996) 1244) undulator radiation contains a broad-band component in the long-wavelength region. This radiation is due to the change in longitudinal velocity of an electron upon entering and leaving an undulator. The radiation pattern is a hollow cone, peaked in the forward direction, with an opening angle of approximately 1γ, with a spectrum covering a wide range, including the infra-red and the visible. The radiation is radially polarized, analogous to transition radiation, and exhibits interference effects between the entrance and exit ends of the undulator, similar to the interference effects observed for transition radiation from a thin slab of material. A straightforward application of formulas from Jackson (JACKSON J. D.,Classical Electrodynamics, 2nd edition (J.Wiley & Sons, N.Y.) 1975) results in a closed-form exact expression for the low-frequency limit of this novel radiation effect, Transition Undulator Radiation or TUR.

At Lawrence Berkeley Laboratory’s Advanced Light Source, three 4.6 m long undulators have been completed, tested, and installed. A fourth is under construction. The completed undulators include two 5.0 cm period length, 89 period devices (U5.0s) which achieve a 0.85 T effective field at a 14 mm minimum gap and a 8.0 cm period length, 55 period device (U8.0) that reaches a 1.2 T effective field at a 14 mm minimum gap. The undulator under construction is a 10.0 cm period length, 43 period device (U10.0) that is designed to achieve 0.98 T at a 23 mm gap. Undulator magnetic gap variation (rms) is within 25 μm over the periodic structure length. Reproducibility of the adjustable magnetic gap has been measured to be within ±5 μm. Gap adjusting range is from 14 to 210 mm, which can be scanned in 1 min. The 5.1 m long vacuum chambers are flat in the vertical direction to within 0.74 mm and straight in the horizontal direction to within 0.08 mm over the 4.6 m magnetic structure sections. Vacuum chamber base pressures after UHV beam conditioning are in the mid-10−11 Torr range and storage ring operating pressures with full current are in the low 10−10 Torr range. Measurements show that the uncorrelated magnetic field errors are 0.23% and 0.20% for the two U5.0s and the U8.0, respectively, and that the field integrals are small over the 1 cm×6 cm beam aperture. Device description, fabrication, and measurements are presented.

The radiation from the 5 cm period undulator at the Advanced Light Source (ALS) has been characterized using a transmission grating spectrometer. Spectral and angular distributions of radiation were measured for deflection parameter K values between 0.45 and 2.12 at low storage ring current (0.1–0.5 mA). From the calibration of the spectrometer, the absolute flux density of the undulator harmonics has been determined together with the spectral linewidth. The electron-beam emittance was determined by analyzing the angular distribution of the redshifted fundamental. Comparison has been made with radiation calculations based upon the measured magnetic-field data of the undulator. Including field errors, electron-beam emittance, and energy spread, good agreement is found between theoretically and experimentally determined harmonic widths and peak brightness.

Insertion devices for the Advanced Light Source (ALS) incorporate up to 3000 magnet blocks each for pole energization. In order to minimize field errors, these magnets must be measured, sorted and assigned appropriate locations and orientations in the magnetic structures. Sorting must address multiple objectives, including pole excitation and minimization of integrated multipole fields from minor field components in the magnets. This is equivalent to a combinatorial minimization problem with a large configuration space. Multi-stage sorting algorithms use ordering and pairing schemes in conjunction with other combinatorial methods to solve the minimization problem. This paper discusses objective functions, solution algorithms and results of application to magnet block measurement data

The first insertion device of the Advanced Light Source (ALS), a U5.0 undulator, has been carefully adjusted and qualified with a specially designed magnetic measurement system. The magnetic field of the undulator has been fully mapped at a series of gaps with very high accuracy. Based upon these measured field data, we evaluate the radiation spectral quality of this device in terms of an ideal sinusoidal device and examine the field error effects. Moreover, the statistical correlation between the field errors and radiation degradation is examined by using the large quantity of magnetic field data sets accumulated in the process of adjusting and qualifying the U5.0 undulator

The end structures for the ALS U5.0 undulators utilize a system of dual permanent magnet rotors intended to establish gap independent field performance. They may also be used for tuning of the first and second magnetic field integrals of these devices. The behavior of these structures has been studied by means of two dimensional modeling with the POISSON Group of computer codes. A parametric study of the magnetic field distribution and first and second integrals of the fields has been conducted. In parallel, magnetic measurements of the final completed structures have been performed using an automated Hall probe measurement system. Results of the modeling and measurements are compared. Implications for tuning of the ends of the devices within the context of the electron beam parameters of the ALS are discussed.<>

LBL -3475 1 UC-406 Lawrence Berkeley Laboratory UNIVERSITY OF CALIFORNIA Accelerator & Fusion Research Division Presented at the NATO Advanced Study Institute, Maratea, Italy, June 28- 1Llly 10, 1992, and to be pUbli shed in the Proceedings The Properties of Undulator Radiation M.R Howells and B.M. Kincaid September 1993 Prepared for the U.S. Department of Energy under Contract Number DE·AC03-76SF00098

Allowable magnetic field errors for the 4.6 m long insertion devices for the Advanced Light Source (ALS) are extremely small and are driven by electron beam and radiation requirements. Detailed measurements and adjustments of each insertion device are performed to qualify them for installation in the ALS. To accomplish this, a high speed, precision magnetic measurement facility has been designed and built. Hall probe mapping equipment, capable of completing a 2500 sample, 6 m scan with precision axial position monitoring using a laser interferometer in under one minute, is used to obtain both local and integrated field information. A 5.5 m long, 1 cm wide coil is used to measure the field integral through an entire insertion device. This paper describes magnetic measurement equipment, and results of measurements on IDA, the first of the ALS insertion devices.< >

The first three undulators, each 4.6 m in length, for the Advanced Light Source (ALS) at Lawrence Berkeley Laboratory (LBL), are near completion and are undergoing qualification tests before installation into the storage ring. Two devices have 5.0-cm period lengths, 89 periods, and achieve an effective field of 0.85 T at the 14 mm minimum magnetic gap. The other device has a period length of 8.0 cm, 55 periods, and an effective field of 1.2 T at the minimum 14 mm gap. Measurements on the first 5 cm period device show the uncorrelated field errors to be 0.23%, which is less than the required 0.25%. Measurements of gap control show reproducibility of ±5 microns or better. The first vacuum chamber, 5.0 m long, is flat to within 0.53 mm over the 4.6 m magnetic structure section and a 4×10-11 Torr pressure was achieved during vacuum tests. Device description, fabrication, and measurements are presented

The U5.0 and U8.0 undulators for the Advanced Light Source incorporate 4.6-m-long, hybrid- configuration magnetic structures. The structures consist of modules with half-period pole assemblies mounted on 0.8-m-long aluminum mounts, which are in turn attached to continuous steel backing beams. The vertical and longitudinal alignment tolerances for the poles of these structures are 25 microns and 50 microns, respectively, over the entire 4.6-m length of the devices. To meet these tolerances, the modules were first aligned individually using an automated coordinate measurement machine and shimming techniques. Several adjustment iterations were required for each module. Averaging and 3D linear least-squares fitting techniques were employed to establish statistically based error reference planes. Graphical spread sheets were used to create representations of vertical and longitudinal pole position errors for alignment.

The U5.0 Undulator, an 89 period, 5 cm period length, 4.6 m long insertion device has been designed, is being fabricated, and is scheduled for completion in early 1992. This undulator will be the first high brightness source, in the 50 to 1,500 eV range, for the Advanced Light Source at the Lawrence Berkeley Laboratory. A hybrid magnetic configuration using Nd–Fe–B permanent magnet material and vanadium permendur poles has been selected to achieve the field quality needed to meet performance requirements. The magnetic structure is modular with each half consisting of five assembly sections, which provide the periodic structure, and end structures, for entrance and exit correction, mounted on a steel backing beam. Each assembly section consists of 35 half-period pole assemblies bolted to a mount. The required 0.837 T effective peak field at a 1.4 cm gap has been verified with model measurements. Vertical field integral correction is accomplished with the end structures, each having an arrangement of permanent magnet rotors which will be adjusted to minimize electron beam missteering over the undulator operating field range. To reduce the effect of environmental fields, the steel backing beams are connected through parallel, low-reluctance, Ni–Fe hinges. The magnetic structure is connected through four rollernuts to the drive system that provides gap adjustment with an arrangement of roller screws, chain drives, a gear reduction unit, and a stepper motor driven by a closed loop control system. Magnetic structure and drive system support are from a 2.4 m high structure which includes a support base with four vertical supports. The vacuum chamber design is a two-piece machined and welded 5083-H321 aluminum construction of 5.1 m length. Pumping is with a combination of ion, titanium sublimation pump and nonevaporable getter pumps. Magnetic design, subsystem design, and fabrication progress are presented.

A knowledge of the position, size, and stability of the source and the angle of emission of synchrotron radiation (SR) from the storage ring are essential for optimizing the operation of storage ring, insertion devices and monochromators. Berkeley’s Advanced Light Source (ALS) has a natural emittance of 3.4×10−9 mrad, and has beam sizes σh and σv (assuming a 10% emittance ratio into the vertical direction) in bending magnet 1 (BM1) of 44 and 83 μm, respectively. Simple diffractive optical calculations show that imaging this beam using visible light optics is not feasible and imaging must be performed using photon energies greater than 50 eV. This will be the same for all third generation low emittance storage rings. The synchrotron radiation diagnostics at ALS will consist of an imaging system for 200 eV photons and a ‘‘white beam’’ port with a streak camera to obtain the timing information. The imaging system will employ two crossed spherical mirrors in a Kirkpatrick–Baez configuration, to eliminate astigmatism. Use of 1:1 imaging will eliminate coma, resulting in an image of the source which is only limited by the residual aberrations of the optics. Real time imaging of the beam is deemed feasible by the use of a high resolution charged coupled device (CCD), and the associated electronics necessary to read the CCD. The design of the imaging system of the diagnostic beamline for ALS and the detection system will be discussed with a view toward applications in other third generation SR sources.

The Advanced Light Source (ALS) is a synchrotron radiation facility based on a low-emittance, 1.5-GeV electron storage ring presently under construction at the Lawrence Berkeley Laboratory, U.S.A. Plans are under way to develop a polarized photon facility at the ALS, exploiting the natural polarization properties of the bend magnet synchrotron radiation. The radiation emitted in the plane of the storage ring is linearly polarized, while above and below the plane it is elliptically polarized. We will utilize these properties to obtain circularly polarized soft x rays. A participating research team (PRT A018) has been formed and is proceeding with the design of a high-resolution beamline in the soft x-ray energy region 100–1500 eV. Intense beams of monochromatic, tunable, pulsed, circularly polarized photons will become available. We will discuss the physical characteristics of this polarized soft x-ray source. New investigations in biology, materials science, physics, and chemistry will become accessible. Initial experiments using circularly polarized photons in the soft x-ray region are planned in the areas of differential scattering and absorption from chiral molecules and probing the electronic and magnetic properties of magnetic systems. This work was supported by the U.S. Department of Energy (DE-AC03-76SF00098).

Author(s): Schlachter, Alfred S.; Cramer, S.; Hunt, A.J.; Kim, K.J.; Kincaid, B.M.; Maestre, M.F.; Marx, J.N.; Nygren, D.R.; Ross, P.N.; Stohr, J.; Wong, M.