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Explosive bonding technology is a good choice to join dissimilar materials, such as 304L stainless steel and GlidCop AL-15, and is used extensively in making the advanced photon source (APS) high-heat-load beamline and front-end components. It is a bonding method in which the controlled energy of a detonating explosive is used to create a metallurgical bond between two or more similar or dissimilar materials. In recent years, special explosive bonding units with rectangular box-type joints were developed for the APS new high-heat-load beamline components. Based on this new technique, the box form of the component could be built in two halves first, then welded together. Therefore, beamline designers have more freedom to optimize the cooling surface geometry.

A great majority of the Advanced Photon Source (APS) users have chosen an undulator as the only source for their insertion device beamline. Compared with a wiggler source, the undulator source has a much smaller horizontal divergence, providing us with an opportunity to optimize the beamline front-end design further. In this paper, the particular designs and specifications, as well as the optical and bremsstrahlung ray-tracing analysis of the new APS front ends for undulator-only operation are presented.

Third-generation synchrotron sources generate strong X-­ray beams. The beam's interaction with biomaterials gives rise to concerns related to thermal damage and radiation damage. Of the two issues, the thermal interaction is conducive to rigorous analysis from first principles, although this has not been performed to date in a comprehensive manner. In this study, the interaction of the X-ray beam emanating from a third-generation synchrotron with a typical frozen biocrystal is theoretically studied, focusing specifically on the resulting unsteady (time-dependent) and steady heat-transfer phenomena. A unique regime map is developed to explain and to identify, on the basis of Fourier and Biot numbers as governing parameters, the applicable mathematical models that predict the subsequent thermal behavior. Depending on the values of these parameters, some simplified but realistic `generic' solutions are generated that are suitable for that particular domain of applicability. Classical heat-transfer theory was used to describe the third-generation X-ray beam and biomaterial thermal interaction. Besides the generalized approach presented, numerous illustrative cases were solved and the resulting temperature levels are explicitly presented. Overall, the resulting thermal behavior of the system, i.e. peak and local temperature distribution, during both early transient development and for sustained long-time steady-state conditions, depends on a number of factors including the amount of energy absorbed, convective heat-transfer film coefficient and gas temperature, the sample size and shape, and the thermophysical properties of the sample and cooling gas. Results of the analysis revealed the strong influence that convection has on the transient and final steady-state temperature of the sample and the impact of internal heat conduction. The characteristic timescales of the important and dominant thermal processes with respect to the two types of thermal models are clearly identified.

Copper mesh, compressed and formed into porous matrices of various shapes and sizes, has been routinely used in high heat load/flux component cooling with water at the Advanced Photon Source (APS) to significantly enhance the heat transfer performance. Now the same mesh configuration is being applied to the cryogenic cooling of optical components, such as the monochromators, mirrors and multilayers with liquid nitrogen in single phase. Two-phase heat transfer is avoided to prevent flow-induced noise (vibrations and jitter) in the ultrasensitive optical components. Hence there is a great need to understand the limits of single-phase heat transfer with copper mesh using liquid nitrogen. Recently an extensive experimental program has been undertaken to investigate the heat transfer limits in conductive porous matrices with liquid nitrogen as the coolant. This paper presents the data obtained, compares the data with existing single- and two-phase correlations, and interprets the results for cryo-cooled optical component cooling applications.

XRAP is a computer code developed for analysis of optical elements in synchrotron radiation facilities that can generate BM (bending magnet) and ID (insertion device) spectra and calculate their absorption in media, such as variable thickness windows/filters and crystals, and provide a finite difference engine for fast but sophisticated thermal and stress analyses for optical elements, such as filters and windows. After a thermal stress analyses, XRAP performs a buckling check. For complex geometries, an interface is provided directly to a finite element code. XRAP features a user‐friendly graphical interface that is based on the X‐window system.

A set of precision, vertical, white‐beam slits has been designed for an undulator/wiggler beamline at the Advanced Photon Source (APS). The slit, a knife‐edge‐type precision device, is required to have very small thermal distortion during operation with beam. The traditional slit consists of a cooling block and an OFHC cooling channel inside the block. The design consists of one large block and an OFHC cooling tube (filled with copper mesh) brazed inside the large block. This design will accommodate the x‐ray source from both undulators and wigglers. Due to the powerful x‐ray heat flux coming from APS Undulator A, it is an exceedingly difficult problem to reduce the thermal distortion to less than 50 μm as required by some users.

The support-system designs for the Advanced Photon Source (APS) front ends are complete and will be installed in 1994. These designs satisfy the positioning and alignment requirements of the front-end components to be installed inside the storage-ring tunnel, including the photon beam position monitors, fixed masks, photon and safety shutters, filters, windows, and differential pumps. Other components include beam transport pipes and ion pumps. The designs comprise 3-point kinematic mounts and single-axis supports to satisfy various multi-direction positioning requirements from coarse to ultra-precise. The confined space inside the storage-ring tunnel has posed engineering challenges in the design of these devices, in view of the fact that some components weigh as much as 500 kg. These challenges include designing for mobility during commissioning and initial alignment, mechanical and thermal stability, and precise low-profile vertical and horizontal positioning. As a result, novel stages and kinematic mounts have been constructed using modular and standard designs. This paper will discuss the diverse group of support systems, including specifications and performance data of the prototypes.

Analyses and evaluation of the life cycle number and crack propagation rate were performed on oxygen-free high-conductivity copper X-ray beamline components based on data available in the literature. Recommendations are made with respect to the safe use of materials in high-heat-load beamline component design. The available literature is critically reviewed for low-cycle fatigue properties at the elevated temperatures typically found in synchrotron operations.

The third generation synchrotron facilities such as the 7-GeV Advanced Photon Source generate X-ray beams with very high heat load and heat flux levels. Certain front end and beamline components will be required to sustain total heat loads of 3.8 to 15 kW and heat flux levels exceeding 400 W/mm 2 even during the first phase of this project. Grazing geometry and enhanced heat transfer techniques in the design of such components reduce the heat flux levels below the 30 W/mm 2 level, which is sustainable by the special copper materials routinely used in the component design. Although the resulting maximum surface temperatures are sustainable, structural stresses and fatigue issues remain important concerns. Cyclic thermal loads have a propensity to cause spallation and thermal striping. As such, the steady-state part of the problem is much easier to understand and handle than the time-dependent part. Ease of bonding as well as ultrahigh vacuum and radiation compatibility are additional constraints on material selection for these components. The two copper materials, which are very commonly used in synchrotron components, are the traditional oxygen-free high-conductivity copper (OFHC) and the newer dispersion-strengthened copper, Glidcop. New materials are also appearing in heat sinks or heat spreaders that are bonded to the base copper in some fashion. These are either partially transparent to X-rays and have engineered volumetric heating and/or are very thermally conductive to spread the thermal load in a preferred way. These materials are reviewed critically for high-heat-load or high-heat-flux applications in synchrotrons.

The first fixed mask is one of the critical elements on the insertion device front ends of the beamlines at the Advanced Photon Source now under construction at Argonne National Laboratory. The heat flux from the undulators will be very large. We simulated the X-ray beam at several locations to ensure that the worst possible case was considered. The maximum temperature (about 180°C) occurs when the beam hits the center of the horizontal surface. The maximum effective stress (about 313 MPa) occurs when the X-ray beam hits at or near the corners.

In the first phase of construction, sixteen insertion-device beamline front ends and sixteen bending-magnet beamline front ends will be built by 1995 for the Advanced Photon Source (APS). Designs for these front ends have been completed. In this paper, the particular designs and specifications as well as the optical and bremsstrahlung ray-tracing analysis for the APS front ends are presented.

Cooling methods and thickness selection of filters and windows are investigated. Safety criteria previously proposed are used to design the filter and window parameters at the Advanced Photon Source. Results are presented on power absorption as well as analytical results from thermal and structural analyses.

To fully understand the behavior of windows after buckling so as to precisely predict failure, this paper first reviews test data and then examines the postbuckling behavior of thin-shell structures under thermal or mechanical load. The paper presents postbuckling analyses of beryllium windows subjected to X-ray thermal loads and investigates the possibility of incorporating elastic buckling into window designs.

A synthetic-diamond-based X-ray transmitting beam-position monitor has been studied using focused white beam at the National Synchrotron Light Source X-25 wiggler beamline. Of particular interest are the possibilities to design an integral window and filter/photon beam-position monitor for the Advanced Photon Source high-heat-flux insertion-device beamlines. The preliminary measurements were taken using two synthetic-diamond blade samples with different thicknesses and cooling configurations. The monitor (consisting of a vacuum vessel, an ion pump, a water-cooling base, a blade mounting block, and electric feedthroughs) was mounted on a three-dimensional ( x , y , φ ) stepping-motor-driven stage with a 0.064-μm stepping size and a 0.1-μm linear encoder resolution. An infrared camera system was used to monitor and record the diamond blade surface temperature field through a sapphire window and test results are presented.

The photon shutter is a critical component of the beamline front end for the 7 GeV Advanced Photon Source (APS) project, now under construction at Argonne National Laboratory (ANL). The shutter is designed to close in tens of milliseconds to absorb up to 10 kW heat load (with high heat flux). Our shutter design uses innovative enhanced heat transfer tubes to withstand the high heat load. Although designed to be lightweight and compact, the very fast movement of the shutter gives rise to concern regarding vibration and dynamic sensitivity. To guarantee long-term functionality and reliability of the shutter, the dynamic behavior should be fully studied. In this paper, the natural frequency and transient dynamic analysis for the shutter during operation are presented. Through analysis of the vibration characteristics, as well as stress and deformation, several options in design were developed and compared, including selection of materials for the shutter and structural details.

The advent of third generation synchrotron radiation sources, like the Advanced Photon Source (APS), will provide significant increases in brilliance over existing synchrotron sources. The APS X-ray undulators will increase the brilliance in the 3–40 keV range by several orders of magnitude. Thus, the design of the photon beam position monitor is a challenging engineering task. The beam position monitors must withstand the high thermal load, be able to achieve submicron spatial resolution while maintaining their stability, and be compatible with both undulators and wigglers. A preliminary APS prototype photon beam position monitor consisting of a CVD-diamond-based, tungsten-coated blade was tested on the APS/CHESS undulator at the Cornell High Energy Synchrotron Radiation Source (CHESS) and on the NSLS X-13 undulator beamline. Results from these tests, as well as the design of this prototype APS photon beam position monitor, will be discussed in this paper.

Recent advances in chemical vapor deposition (CVD) technology have made available thin, free-standing polycrystalline diamond foils that can be used as the window material on high heat load synchrotron X-ray beamlines. Diamond windows have many advantages that stem from the exceptionally attractive thermal, structural, and physical properties of diamond. Numerical simulations indicate that diamond windows can offer an attractive and at times the only alternative to beryllium windows for use on the third generation X-ray synchrotron radiation beamlines. Utilization, design, and fabrication aspects of diamond windows for high heat load X-ray beamlines are discussed, and analytical and numerical results are presented to provide a basis for the design and testing of such windows.

The photon shutter is one of the critical elements on the front end of the beamlines at the Advanced Photon Source (APS) now under construction at Argonne National Laboratory (ANL). The conceptual design of the photon shutter uses an enhanced heat transfer tube developed at ANL. Due to large thermal loads on the shutter, inclined geometry is used in the design to spread the footprint of the X-ray beam. Even then, thermal loads are very critical. To address the thermal and thermomechanical issues, analytical studies have been applied to a simplified model of the shutter tube. Both closed-form solutions and ANSYS finite element analysis are conducted using both a uniform and a Gaussian heat flux. Results for maximum deflections and stresses are obtained and compared with the available stress/fatigue data for the materials proposed for the shutter design.

The conceptual designs for the insertion device (ID) and bending magnet (BM) front ends have been completed for the 7 GeV Advanced Photon Source (APS) under construction at Argonne National Laboratory. These designs satisfy the generic front end functions. However, the high power and high heat fluxes imposed by the X-ray sources of the 7 GeV APS have presented various design engineering challenges for the front end. Consideration of such challenges and their solutions have led to novel and advanced features including modularized systems, enhanced heat transfer concepts in the fixed mask and the photon shutter designs, a radiation safety philosophy based on multiple photon shutters for a fail-safe operation, a submicron resolution beam position monitor for beam monitoring and ring feedback information, and minimal beam filtering concepts to deliver maximized beam power and spectra to the experimenters. The criteria and special features of the front end design are discussed in this paper.

It is well established that Si and SiC have very desirable thermophysical properties (principally, high thermal conductivity, and low thermal expansion) at cryogenic temperatures. Thus, cryocooled optics are a potentially good candidate for the first optical crystal of the third generation synchrotron machines, which will have very high heat flux levels. Currently, there is a great deal of interest, both experimental and analytical in such cryocooled crystals. The analytical studies involve cut micro‐ or capillary channel crystals. As opposed to machined channels, porous matrices provide significant advantages. Such matrices are known to effect superior heat transfer. They operate very quietly. Data available in the open literature suggest that surface heat flux levels up to ∼8 kW/cm2 are possible. For cryogens for which the boiling heat transfer heat flux is a rather low value in conventional geometries, the enhancement available with such matrices is very significant. Cryogens are poor thermal conductors themselves. At cryogenic temperatures, the Si and/or SiC matrix itself becomes highly conductive: Thus, the matrix distributes the surface heat flux into the full volume effectively offsetting the poor conductivity of the coolant. In addition, the tortuous path of the coolant through the matrix increases the dwell time resulting in better heat transfer, however, at the expense of an increased pressure drop. In this study, a first optics crystal model of Si with a Si and/or SiC porous matrix as its heat exchanger and subject to prototypic synchrotron loads is analyzed, and the feasibility limits of the cooling possible with liquid nitrogen in single phase are delineated.

A novel X-ray beam-position detection device that we call a position-sensitive photoconductive detector (PSPCD) is designed to have synthetic diamond as its substrate material. We proved that it is feasible to use synthetic diamond to make a hard X-ray position-sensitive detector based on the photoconductivity principle and that it acts as a solid-state ion chamber. Experiments on different PSPCD samples using synthetic diamond with a high-heat-flux white undulator beam, as well as with monochromatic hard X-ray beams, have been performed at the Advanced Photon Source. Recent test results with the PSPCD in the quadrant configuration as an X-ray beam-position monitor and in a multipixel array as an X-ray beam profiler are presented in this paper.

Explosive bonding is a bonding method in which the controlled energy of a detonating explosive is used to create a metallurgical bonding between two or more similar or dissimilar materials. Since 1991, a number of explosive bonding joints have been designed for high‐thermal‐load ultrahigh‐vacuum (UHV) components in the Advanced Photon Source. A series of standardized explosive bonded joint units has also been designed and tested, such as oxygen‐free copper (OFHC) to stainless‐steel vacuum joints for slits and shutters, GlidCop (GlidCop is a trademark of SCM Metal Products, Inc.) to stainless‐steel vacuum joints for fixed masks, and GlidCop to OFHC thermal and mechanical joints for shutter face plates, etc. The design and test results for the explosive bonding units to be used in the Advanced Photon Source front ends and beamlines will be discussed in this paper.

The Advanced Photon Source (APS) has initiated a design standardization and modularization activity for the APS synchrotron radiation beamline components. These standard components are included in components library, subcomponents library, and experimental station library. This paper briefly describes these standard components using both technical specifications and sideview drawings.

A concept that uses a variable thickness window for a synchrotron radiation beamline is proposed here for third‐generation synchrotron x‐ray facilities that can generate a very bright x‐ray beam in a very small area. The finite difference method is used to perform the variable thickness heat‐transfer analysis and variable thickness plane stress analysis. Application of the variable thickness window to an advanced photon source beamline is presented.

The pin‐fin configuration is widely used in high‐heat‐flux applications. Recently, the pin‐fin design with liquid‐metal coolant was also applied to synchrotron‐radiation beamline devices. This article investigates the pressure drop in a pin‐post crystal with liquid gallium as the coolant. Because the pin‐post configuration is a relatively new concept, information in the literature on pin‐post mirrors or crystals is rare, and information on the pressure drop in pin‐post mirrors with liquid metal as the coolant is even rarer. Because the cross flow in cylinder‐array geometry is very similar to that of the pin post, the pressure drop correlation data for the cross flow of fluid with various fluid characteristics or properties through a tube bank are studied so that the results can be scaled to the pin‐fin geometry with liquid metal as the coolant. The emphasis of this article is on the influence of two variables on the pressure drop: viscosity and density of fluid. The difference and correlation of the press...

The analytical results and design considerations for a cryogenically cooled advanced photon source (APS) silicon monochromator are presented. The high conductivity and low thermal expansion coefficient of silicon at cryogenic temperatures are advantages that are used to solve the high‐heat‐flux problem from undulator radiation. The APS monochromator features a machined slot with variable thicknesses below the surface. This configuration is designed to reduce absorption by the crystal and decrease the maximum temperature of the crystal. The transmitted power through the crystal is absorbed by a second element that can be cooled by standard cooling techniques. Different parameters and configurations are analyzed to maximize the performance of the monochromator and minimize the total absorbed power by the crystal.

A set of precision horizontal and vertical white‐beam slits has been designed for the Advanced Photon Source x‐ray undulator beamlines at Argonne National Laboratory. There are several new design concepts applied in this slit set, including a grazing‐incidence knife‐edge configuration to minimize the scattering of x rays downstream, enhanced heat transfer tubing to provide water cooling, and a secondary slit to eliminate the thermal distortion on the slit knife edge. The novel aspect of this design is the use of two L‐shaped knife‐edge assemblies, which are manipulated by two precision X‐Z stepping linear actuators. The principal and structural details of the design for this slit set are presented in this paper.

A set of horizontal and vertical white‐beam slits has been designed for the Advanced Photon Source wiggler/undulator beamlines at Argonne National Laboratory. While this slit set can handle the high heat flux from one APS undulator source, it has a large enough aperture to be compatible with a wiggler source also. A grazing‐incidence, knife‐edge configuration has been used in the design to eliminate downstream x‐ray scattering. Enhanced heat transfer technology has been used in the water‐cooling system. A unique stepping parallelogram driving structure provides precise vertical slit motion with large optical aperture. The full design detail is presented in this paper.

A generic vibratory-response modeling program has been developed as a tool for designing high-precision optical positioning systems. Based on multibody dynamics theory, the system is modeled as rigid-body structures connected by linear elastic elements, such as complex actuators and bearings. The full dynamic properties of each element are determined experimentally or theoretically, then integrated into the program as inertial and stiffness matrices. Utilizing this program, the theoretical and experimental verification of the vibratory behavior of a double-multilayer monochromator support and positioning system is presented. Results of parametric design studies that investigate the influence of support floor dynamics and highlight important design issues are also presented. Overall, good matches between theory and experiment demonstrate the effectiveness of the program as a dynamic modeling tool.

Copper mesh, compressed and formed into porous matrices of various shapes and sizes, has been routinely used in high heat load/flux component cooling at the Advanced Photon Source (APS) to significantly enhance the heat transfer performance. Substantial research has been performed at the APS over the last eight years in order to better quantify and optimize the selection of the mesh copper matrix attributes (porosity, wire size, core size, bonding technique, etc.) for various water-cooled component applications in single phase. The same mesh configuration can also be applied in cryogenic cooling of optical components, such as monochromators, mirrors and multilayers, with liquid nitrogen. This paper reviews the experimental data and the analytical calculations, compares the data with existing single- and two-phase correllations, and interprets the results for a cryogenically cooled monochromator.

A novel laser Doppler linear encoder system (LDLE) has been developed at the Advanced Photon Source, Argonne National Laboratory. A self-aligning 3-D multiple-reflection optical design was used for the laser Doppler displacement meter (LDDM) to extend the encoder system resolution. The encoder is compact [about 70 mm(H) x 100 mm(W) x 250 mm(L)] and it has sub-Angstrom resolution, 100 mm/sec measuring speed, and 300 mm measuring range. Because the new device affords higher resolution, as compared with commercial laser interferometer systems, and yet cost less, it will have good potential for use in scientific and industrial applications.

A generic vibratory response-modeling program has been developed as a tool for designing high-precision optical positioning systems. The systems are modeled as rigid-body structures connected by linear non-rigid elements such as complex actuators and bearings. The full dynamic properties of each non-rigid element are determined experimentally or theoretically, then integrated into the program as inertial and stiffness matrices. Thus, it is possible to have a suite of standardize structural elements for modeling many different positioning systems that use standardized components. This paper will present the application of this program to a double-multi-layer monochromator positioning system that utilizes standardized components. Calculated results are compared to experimental modal analysis results.

Optical support systems actuated by multi-degree-of$reedom, high-precision positioning stages are used for beamlinecomponents at the Advanced Photon Source (APS) at Argonne National Laboratory. Positioning precision and stability fr these components is critical as they interface with a high-brilliance synchrotron radiation beam. Stability may be compromised by seismic and facility-borne vibrations traveling through the ground and/or vibrations from flow/structureinteractions in the cooling systems ofthe mounted optical components. A study was undertaken to develop accurate modelsthat predict support system response to vibratory excitations. The dynamic properties ofthe complex linkages and joints thatcomprise the positioning systems are not easily described by simple formulations. In this article, improved models fbr thesedevices have been developed via theoretical, computational and experimental techniques. Linkage component models aiintegrated into a multi-body system model, which is then used to predict the dynamic response of the optical positioningassembly. Predicted mode shapes and natural frequencies compare well with experimental findings. These models can nowthen be used to facilitate future design improvements for the next-generation beamlines.Keywords: multibody systems, positioning stability, optics, vibration isolation, synchrotron radiation

A compact and high-heat-load absorber for the SPring-8 X-ray undulator beamline has been developed and installed. It consists of an upper heat-absorber part and a lower photon duct part, which are configured together in a water-cooled GlidCop body. The absorber part has a horizontal notch shape and the photon duct part forms a rectangular open channel under the absorber part. Two types of absorber are designed: one, with wire mesh channels, is 486 mm long, 70 mm high and 64 mm wide; the other, with smooth-bore channels, is 610 mm long, 75 mm high and 70 mm wide. Thermal and stress analyses show that they withstand the 12.3 kW heat load and the maximum heat flux of 940 W mm−2 at normal incidence.

At the Advanced Photon Source (APS), a state-of-the-art synchrotron radiation facility at Argonne National Laboratory (ANL), high-precision optical positioning systems are needed to conduct a wide range of experiments using the high-brilliance X-ray beam. Precision may be compromised by low-level, low- frequency vibrations from flow-structure interactions in the cooling systems and from facility-based disturbances propagating through the floor. To predict the vibratory response of the positioning systems, a linearized multibody formulation has been developed. It has been applied to specific example cases--an optical table and a mirror support system--used at the experimental stations of the APS. Comparisons of resonant frequency and mode shape predictions based on the theoretical formulation with experimental measurements illustrate the crucial importance of properly modeling the kinematic joints and components that comprise these multibody structures. Improved experimental and theoretical methods have been introduced to estimate their dynamic properties. The results obtained by theory compare well with experimental findings. The proposed methodology is precise and generic in predicting the coupled multidimensional, multi-degree-of-freedom vibratory motion of the positioning systems for the given positioning configurations. It is easily adaptable to numerous systems at the APS and similar facilities.

At the Advanced Photon Source (APS), each insertion-device (ID) beamline front end has two X-ray beam position monitors (XBPMs) to monitor the X-ray beam position for both vertical and horizontal directions. Performance challenges for a conventional photoemission-type XBPM during operations are contamination of the signal from the neighbouring bending-magnet sources and the sensitivity of the XBPM to the insertion-device gap variations. Problems are exacerbated because users change the ID gap during their operations, and hence the percentage level of the contamination in the front-end XBPM signals varies. A smart XBPM system with a high-speed digital signal processor has been built at the Advanced Photon Source for the ID beamline front ends. The new version of the software, which uses an artificial-intelligence method, provides a self-learning and self-calibration capability to the smart XBPM system. The structure of and recent test results with the system are presented in this paper.

Several novel design developments have been established for the Advanced Photon Source (APS) insertion device (ID) X-ray beam position monitor (XBPM) to improve its performance: --- optimized geometric configuration of the monitor’s sensory blades; --- smart XBPM system with an intelligent digital signal processor, which provides a self-learning and calibration function; and --- Transmitting XBPM with prefiltering in the commissioning windows for the front end. In this write-up, we summarize the recent progress on the XBPM development for the APS ID front ends.

This paper reports a thermo-mechanical study of a beamline filter for undulator/wiggler operations.It is deployed in conjunction with the current commissioning window assembly on the APS insertion device (ID) front ends. The beamline filter at the APS will eventually be used in windowless operations also. Hence survival and reasonable life expectancy of the filters under intense ID heat flux are crucial to the beamline operations. To accommodate various user requirements, the filter is configured to be a multi- choice type and 'smart' to a low only those filter combinations that will be safe to operate with a given ring current and beamline insertion device gap. However, this paper addresses only the thermo-mechanical analysis of individual filter integrity and safety in all combinations possible. The current filter design is configured to have four filter frames in a cascade with each frame holding five filters. This allows a potential 625 total filter combinations. Thermal analysis for all of these combinations becomes a mammoth task considering the desired choices for filter materials, filter thicknesses, undulator gaps, and the beam currents. The paper addresses how this difficult task has been reduced to a reasonable effort and computational level. Results from thermo-mechanical analyses of the filter combinations are presented both in tabular and graphical format.

The vibratory response of a typical mirror support/positioning system used at the experimental stations of the advanced photon source (APS) project at Argonne National Laboratory is investigated. Positioning precision and stability are especially critical when the supported mirror directs a high-intensity beam aimed at a distant target. Stability may be compromised by low level, low frequency seismic and facility-originated vibrations traveling through the ground and/or vibrations caused by flow-structure interactions in the mirror cooling system. The example case system has five positioning degrees of freedom through the use of precision actuators and rotary and linear bearings. These linkage devices results in complex, multi-dimensional vibratory behavior that is a function of the range of positioning configurations. A rigorous multibody dynamical approach is used for the development of the system equations. Initial results of the study, including estimates of natural frequencies and mode shapes, as well as limited parametric design studies, are presented. While the results reported here are for a particular system, the developed vibratory analysis approach is applicable to the wide range of high-precision optical positioning systems encountered at the APS and at other comparable facilities.

Ozone is generated in the APS experimental stations whenever the x-ray beam has a chance to interact with air. Ozone concentrations in an experimental station have to be below a certain defined limit (current OSHA regulations specify 0.08 ppm as the maximum limit) before an experimenter can reenter the hutch. This limit is said to be currently under study for a downward adjustment. One method of depleting the ozone generated in an experimental station is mitigation through either adsorption or direct destruction. In recent tests, both methods were tried using commercially available units. Test results and some analytical predictions are presented.

Synchrotron x-ray windows are vacuum separators and are usually made of thin beryllium metal. Filters are provided upstream of the window to filter out the soft x-rays to protect the window from overheating and failing. The filters are made of thin carbon products or sometimes beryllium, the same material as the window. Because the window is a vacuum separator, understanding its potential structural failure under thermal load is very important. Current structural failure models for the brazed windows and filters under thermal stresses are not very accurate. Existing models have been carefully examined and found to be inconsistent with the actual failure modes of windows tested. Due to the thinness of the filter/window, the most likely failure mode is thermal buckling. In fact, recent synchrotron tests conducted in Japan on window failures bear out this position. In this paper, failure criteria for filters/windows are proposed, and analyses are performed and compared with the experimental results from various sources. A consistent result is found between the analysis and reported experiments.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A new ultra-high-vacuum (UHV) compatible coaxial water cooling structure has been designed for the Advanced Photon Source high-power bending-magnet front-end photon shutters. Laser- beam thermal-simulation test results show that this new cooling structure can provide more than 1.56 kW total power cooling capacity with 12.3 W/mm2 maximum surface heat flux. The maximum surface temperature is lower than 116 degree(s)C.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The photon shutters (PS) on the insertion device front end of the beamlines at theAdvanced Photon Source (APS) are designed to fully intercept powerful 7-GeV undula-tor radiation. Traditional materials (oxygen-free copper and Glidcop) are used in theirconstruction. Initially, the APS proposes to operate the storage ring at 100 mA. In laterphases of operation, the APS will operate the storage ring at 300 mA. The heat fluxfrom the undulators is enormous. For example, in the later phase of the project, thefirst photon shutter (PSi) placed at a distance of 17 rn from the Undulator A sourcewill be subjected to 1400 W/rnrn2 at normal incidence with a total power of 11.4 kW.The PS uses an enhanced heat transfer mechanism developed at Argonne NationalLaboratory, which increases the convective heat transfer coefficient to about 3 W/crn2. oc withsingle phase water as the coolant. To be able to handle the expected three-foldincrease in the intense heat flux, some low-Z materials (such as beryllium or graphite),which can absorb the xra,rs through their thickness, are now considered as the facingmaterial on the absorber base plate of the PS.Our analysis ofPSl indicates that the face plate made ofeither graphite or berylliumretains its integrity in most of the cases. The maximum effective stress of the absorberplate (made of annealed OFHC) exceeds the yield strength (50 MPa) except in the caseof an absorber with a 10-mm graphite face plate.

One of the most critical components on the Advanced Photon Source (APS) insertion device (ID) beamline front ends is the first photon shutter. It operates in two modes to fully intercept the high total power and high-heat-flux ID photon beam in seconds (normal mode) or in less than 100 ms (emergency fast mode). It is designed to operate in ultra high vacuum (UHV). The design incorporates a multi-channel rectangular bar, bent in a `hockey stick' configuration, with two-point suspension. The flanged end is an articulated bellows with rolling hinges. The actuation end is a spring-assisted, pneumatic fail-safe flexural pivot type. The coolant (water) channels incorporate brazed copper foam to enhance the heat transfer, a tube technology particular to the APS. The design development, and material aspects, as well as the extensive thermal and vibrational analyses in support of the design, are presented in this paper.

The powerful beams of x-ray radiation generated by insertion devices at high power synchrotron facilities deposit substantial amounts of localized heat in the front end and optical components that they intercept. X-ray beams from undulator sources in particular are confined to very narrow solid angles and therefore impose very high absorbed heat fluxes. This paper is devoted to a detailed study of the design of windows for the Advanced Photon Source undulators and wigglers emphasizing alternative design concepts material considerations and cooling techniques necessary for handling the high heat load of the insertion devices. Various designs are thermally and structurally analyzed by numerically simulating full-power operating conditions. This analysis also has relevance to the design and development of other beam line components which are subjected to the high heat loads of insertion devices. Key indices: synchrotron radiation high heat load insertion devices undulators wigglers beryllium window. 2.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Advanced Photon Source (APS) to be constructed at Argonne National Laboratory (ANL) utilizes magnetic devices which generate X-ray beams with very intense heat flux levels. The Fixed Mask Assembly (FMA) is the first component to interact with the X-ray beam. Two sets of a pair of FMA channels vertically and horizontally disposed contain the beam rather than define it. They are subject to very large heat fluxes during containment. In current practice the FMA channels are made of heavy seamless copper have rectangular cross-sections and are cooled internally with water. Channels are set at grazing angles ranging from 1 to 6 degrees with respect to the beam depending on the type of insertion device. APS insertion devices will impose higher heat fluxes on FMAs. Therefore a need exists to improve the FMA engineering keeping in mind the current design criteria and philosophy of FMAs. A comparative investigation of the conventionally achievable heat transfer coefficient h" with water and the wall conductance of a heavy wall copper tube reveals that major resistance is on the coolant side. Therefore there exists a significant opportunity to improve heat transfer in the tubes by enhancement of the coolant side. To this end an experimentally and analytically based research program has been adopted at the APS for investigating enhanced cooling methods and techniques. Currently a variety of copper wool filled tubes as well as a© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Fixed Mask Assembly (FMA) is the first component to interact with the photon beam. Two sets of a pair of FMA channels, vertically and horizontally disposed, contain the beam rather than define it. They are subject to very large heat fluxes during containment. In current practice, the FMA channels are made of heavy, seamless copper, have rectangular cross-sections, and are cooled internally with water. Channels are set at grazing angles ranging from 1 to 6 degrees with respect to the beam, depending on the type of insertion device. APS insertion devices will impose higher heat fluxes on FMAs. Therefore, a need exists to improve the FMA engineering, keeping in the mind the current design criteria and philosophy of FMAs. Preliminary analysis of current heat transfer practice indicates that the major resistance to heat transfer is on the coolant side. Therefore, FMA cooling would benefit from enhanced heat transfer on the coolant side. With this principle in mind, an experimental program has been undertaken to explore the feasibility of using high-performance copper tube configurations which are expected to yield heat transfer coefficients, h, '' in single phase flow systems 2 to 5() times higher than equivalent plain tubes. In this report, the experimental scope and a preliminary analysis of high-performance copper tube configurations are described.

A compact filter/mask/window assembly has been designed for undulator beamline commissioning activity at the Advanced Photon Source beamlines. The assembly consists of one 300-{mu}m graphite filter, one 127-{mu}m CVD diamond filter and two 250-{mu}m beryllium windows. A water-cooled Glidcop fixed mask with a 4.5-mm {times} 4.5-mm output optical aperture and a 0.96-mrad {times} 1.6-mrad beam missteering acceptance is a major part in the assembly. The CVD diamond filter which is mounted on the downstream side of the fixed mask is designed to also function as a transmitting x-ray beam position monitor. The sum signal from the latter can be used to monitor the physical condition of the graphite filter and prevent any possible chain reaction damage to the beryllium windows downstream. In this paper, the design concept as well as the detailed structural design of the commissioning window are presented. Further applications of the commissioning window commissioning window components are also discussed.

A modular filter has been designed for the white‐beam undulator/wiggler beamlines at the Advanced Photon Source. For a typical hard x‐ray application, the filter assembly consists of four filter banks, and each bank has five beam apertures. Therefore a maximum of 625 filter combinations is mechanically possible. To prevent any mistaken setup, which could either damage the filter itself or downstream optical components, a programmable logic controller (PLC) based protection system has been designed. Fuzzy logic was used in this system to limit the memory size and improve the system performance. Ten different storage‐ring beam currents and ten insertion‐device gap setups have been chosen to cover a large dynamic operation range. Aspects of the system fuzzy logic design as well as an example of the calculated results for the control database are presented in this paper.