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6 GeV light source project cost estimating procedure

Description: To maintain uniformity in estimating the cost requirements of the various components of the 6 GeV Light Source, the following procedure will be used by all the task groups. The procedure uses a Work Breakdown Structure (VBS) to break down the project into manageable, easy to estimate, components. The project is first broken down into major tasks or categories. Then each major division is continuously subdivided until the desired level of detail is achieved. This can be shown best by using the example of the WBS of the Aladdin Upgrade Project, excerpts of which are included in Appendix A.
Date: October 23, 1985
Partner: UNT Libraries Government Documents Department

Performance of the TLS at SRRC

Description: 3-year operation experiences of the 1.3 GeV synchrotron radiation facility at SRRC are presented. Two insertion devices (W20 and U10p) are installed in the storage ring; more are under construction. Single bunch instabilities were measured and ring impedance calculated. Both transverse and longitudinal coupled bunch instabilities were observed and corresponding feedback system constructed. The transverse feedback system is now routinely operated. A fast global orbit feedback system is in the development stage. Lifetime is about 5 hours at 200 mA; plans to increase lifetime are proposed. At present, the machine can be operated at nominal design energy 1.3 GeV with full energy injection and ramped up to 1.5 GeV at 200 mA.
Date: October 1, 1996
Creator: Liu, Y.C.; Chen, J.R.; Chang, C.H.; Hsu, K.T. & Kuo, C.C
Partner: UNT Libraries Government Documents Department

Innovations in the design of mechanical components for a beamline -- The SRl`95 Workshop 2 summary

Description: The Synchrotron Radiation Instrumentation 1995 Conference (SRI`95) was hosted by the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). Of the many workshops within the conference, the SRI`95 Workshop 2 was ``Innovations in the Design of Mechanical Components of a Beamline``. The workshop was attended well with over 140 registrants. The following topics were discussed. Industry`s perspective on the status and future was provided by Huber Diffrationtechnik, Oxford Instruments, and Kohzu Seiko Ltd. on goniometers/diffractometers, advanced manufacturing technique of high heat load components, such as the APS photon shutter, and the specialties of monochromators provided to the third-generation synchrotrons, respectively. This was followed by a description of the engineering of a dual function monochromator design for water-cooled diamond or cryogenically cooled silicon monochromators by CMC CAT/APS. Another category was the nagging problem of sensitivity of the photon beam position monitors (XBPM) to bending magnet radiation (``BM contamination``) and the undulator magnet gap changes. Problem descriptions and suggested solutions were provided by both the Advanced Light Source (ALS) and the APS. Other innovative ideas were the cooling schemes (enhanced cooling of beamline components using metallic porous meshes including cryo-cooled applications); Glidcop photon shutter design using microchannels at the ALS; and window/filter design, manufacture and operational experiences at CHESS and PETRA/HASYLAB. Additional discussions were held on designing for micromotions and precision in the optical support systems and smart user filter schemes. This is a summary of the presentations at the Workshop. 5 refs., 5 figs.
Date: December 31, 1995
Creator: Kuzay, T.M. & Warwick, T.
Partner: UNT Libraries Government Documents Department

Long wavelength end-effect undulator radiation (Transition Undulator Radiation)

Description: As first pointed out by K.-J. Kim, 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 1/{gamma}, 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 ({ital Classical Electrodynamics}) results in a closed form exact expression for the low frequency limit of this novel radiation effect, Transition Undulator Radiation or TUR. 3 refs., 3 figs.
Date: January 29, 1996
Creator: Kincaid, B.M.
Partner: UNT Libraries Government Documents Department

Recent x-ray observations of intermediate BL Lac objects

Description: We present recent ROSAT, ASCA and SAX observations of intermediate BL Lac objects (IBLs), i.e. BL Lacs which are located between high-energy and low-energy peaked BL Lac objects with respect to log (S<sub>x</sub>/S<sub>r</sub>). Both, the statistical properties of IBLs from the RGB sample and a detailed broad band X-ray spectral analysis of two objects (1424+2401, 1055+5644), point towards a continuous distribution of synchrotron emission peak frequencies among BL Lac objects.
Date: June 1, 1998
Creator: Brinkmann, W; Laurent-Muehleisen, S & Siebert, J
Partner: UNT Libraries Government Documents Department

Two-Color Experiments Combining the UV-Storage Ring Free Electron Laser and SA5 IR Beamline at Super-ACO

Description: This article reviews pump-probe experiments with a storage ring based free-electron laser pump, and synchrotron radiation as a broadband spectroscopic probe.
Date: July 19, 1999
Creator: Nahon, Laurent; Renault, Eric; Couprie, Marie-Emmanuelle; Nutarelli, Daniele; Garzella, David; Billardon, Michel et al.
Partner: UNT Libraries Government Documents Department

Estimates of dispersive effects in a bent NLC Main Linac

Description: An alternative being considered for the Next Linear Collider (NLC) is not to tunnel in a straight line but to bend the Main Linac into an arc so as to follow a gravitational equipotential. The authors begin here an examination of the effects that this would have on vertical dispersion, with its attendant consequences on synchrotron radiation and emittance growth by looking at two scenarios: a gentle continuous bending of the beam to follow an equipotential surface, and an introduction of sharp bends at a few sites in the linac so as to reduce the maximum sagitta produced.
Date: October 31, 2000
Creator: Michelotti, Michael Syphers and Leo
Partner: UNT Libraries Government Documents Department

Synchrotron radiation interferences between small dipoles at LEP

Description: Synchrotron Radiation interferences between small dipoles in the very low (visible) frequency range have been studied at the LEP diagnostic mini-wiggler. Their understanding allowed a substantial brightness gain by adequate layout modifications. The phenomenon is described analytically in terms of time coherence effects. This serves as a basis for further detailed numerical simulations of the experiment by means of stepwise ray-tracing, and allows precise interpretation of the spectral, polarization and intensity measurements collected at LEP. It also provides guidelines for SR diagnostic at injection energy in LHC.
Date: June 1, 1997
Creator: Bovet, C., Burns, A., Meot, F., Placidi, M., Rossa, E., de Vries, J.
Partner: UNT Libraries Government Documents Department


Description: The mechanical design considerations are discussed with respect to the currently installed X-13 and future X-29 MGU. Comparisons to the previous 2 generations of variable small-gap undulator evolution in the NSLS X-ray ring are made and design improvements noted. The design requirements and mechanical difficulties for holding, positioning and driving the magnetic arrays are explored. Structural, thermal and electrical considerations which influenced the design are then analyzed. The mechanical performance of the MGU currently installed at X-13 is examined and future installations and enhancements are presented.
Date: September 5, 2002
Partner: UNT Libraries Government Documents Department

Ring Energy Selection and Extra Long Straight Sections for the Advanced Photon Source

Description: Recommended criteria are given for the performance of Advanced Photon Source (APS), taking into consideration undulator tunability criteria and their relationship to the storage ring energy and undulator gap, length of straight sections.
Date: April 1987
Creator: Brown, G.; Cho, Y.; Hastings, J.; Krinsky, S.; Moncton, D. E.; Shenoy, G. K. et al.
Partner: UNT Libraries Government Documents Department

Insertion Device and Beam Line Plans for the Advanced Photon Source : a Report and Recommendations by the Insertion Device and Beam Line Planning Committee

Description: In the 7-GeV Advanced Photon Source (APS) Conceptual Design Report (CDR), fifteen complete experimental beam lines were specified in order to establish a representative technical and cost base for the components involved. In order to optimize the composition of the insertion devices and the beam line, these funds are considered a ''Trust Fund.'' The present report evaluates the optimization for the distribution of these funds so that the short- and long-term research programs will be most productive, making the facility more attractive from the user's point of view. It is recommended that part of the "Trust Fund" be used for the construction of the insertion devices, the front-end components, and the first-optics, minimizing the cost to potential users of completing a beam line. In addition, the possibility of cost savings resulting from replication and standardization of high multiplicity components (such as IDs, front ends, and first-optics instrumentation) is addressed.
Date: February 1987
Creator: Boyce, R.; Hewitt, R.; Morrison, T. I.; Shenoy, G. K.; Thomlinson, W. & Viccaro, P. J.
Partner: UNT Libraries Government Documents Department

An Overview of the Characteristics of the 6-GeV Synchrotron Radiation : a Preliminary Guide for Users

Description: In this document we present the characteristics of the electromagnetic radiation from various types of sources on a 6-GeV storage ring. The sources include bending magnets, undulators and wigglers. The characteristics are compared with those of other synchrotron sources when operated at their design specifications. The influence of positron beam size on the brilliance is discussed, along with the power distribution from these sources. The goal of this document is to provide users with enough information on the behavior of radiation from a 6-GeV storage ring so that a dialogue can be established with the accelerator physicists and engineers to achieve an optimal design.
Date: October 1985
Creator: Shenoy, G. K. & Viccaro, P. J.
Partner: UNT Libraries Government Documents Department

Installation of a Synchrotron Radiation Beamline Facility at the J. Bennett Johnston Center. Final Report

Description: The Johnston Center presents a unique opportunity for scientists and engineers at southern institutions to initiate and carry out original research using synchrotron radiation ranging from visible light to hard x-rays. The Science and Engineering Alliance proposes to carry out a comprehensive new synchrotron radiation research initiative at CAMD in carefully phased steps of increasing risks. (1) materials research on existing CAMD beam lines and end stations; (2) design, construction and installation of end stations on existing CAMD beam lines, and research with this new instrumentation; (3) design, construction and operation of dedicated synchrotron radiation beam lines that covers the full spectral range of the CAMD storage ring and expanded research in the new facility.
Date: March 21, 2000
Creator: Gooden, R.
Partner: UNT Libraries Government Documents Department

Evolving bunch and retardation in the impedance formalism

Description: The usual expression for the longitudinal wake field in terms of the impedance is exact only for the model in which the source of the field is a rigid bunch. To account for a deforming bunch one has to invoke the complete impedance, a function of both wave number and frequency. A computation of the corresponding wake field would be expensive, since it would involve integrals over frequency and time in addition to the usual sum over wave number. We treat the problem of approximating this field in an example of current interest, the case of coherent synchrotron radiation (CSR) in the presence of shielding by the vacuum chamber.
Date: May 22, 2003
Creator: Warnock, Robert & Venturini, Marco
Partner: UNT Libraries Government Documents Department


Description: Profiling instruments are well-suited to the measurement of grazing incidence optics, such as those found in synchrotron radiation beam lines. Slope measuring profilers, based upon the principle of the pencil beam interferometer, have proven to be especially useful in measuring the figure and slope errors on cylindrical aspheres. The Long Trace Profiler, in various configurations, is the most widely used of this class of profiler. Current performance provides slope measurement accuracy at the microradian level and height measurements accurate to 25 nm over 1 meter trace lengths.
Date: January 14, 2003
Creator: TAKACS,P.Z.
Partner: UNT Libraries Government Documents Department

Determination of ionization energies of CnN (n=4-12): Vacuum-ultraviolet (VUV) photoionization experiments and theoretical calculations

Description: Results from single photon vacuum ultraviolet photoionization of astrophysically relevant CnN clusters, n = 4 - 12, in the photon energy range of 8.0 eV to 12.8 eV are presented. The experimental photoionization efficiency curves, combined with electronic structure calculations, provide improved ionization energies of the CnN species. A search through numerous nitrogen-terminated CnN isomers for n=4-9 indicates that the linear isomer has the lowest energy, and therefore should be the most abundant isomer in the molecular beam. Comparison with calculated results also shed light on the energetics of the linear CnN clusters, particularly in the trends of the even-carbon and the odd-carbon series. These results can help guide the search of potential astronomical observations of these neutral molecules together with their cations in highly ionized regions or regions with a high UV/VUV photon flux (ranging from the visible to VUV with flux maxima in the Lyman- region) in the interstellar medium.
Date: June 10, 2010
Creator: Kostko, Oleg; Zhou, Jia; Sun, Bian Jian; Lie, Jie Shiuan; Chang, Agnes H.H.; Kaiser, Ralf I. et al.
Partner: UNT Libraries Government Documents Department

Monitoring performance of the Advanced Light Source

Description: Providing high quality light to users in a consistent and reliable manner is one of the main goals of the accelerator physics group at the Advanced Light source (ALS). To meet this goal considerable time is spent monitoring the performance of the machine. At the Group's weekly meeting the performance of the accelerator over the previous week's run is reviewed. This paper describes the parameters that are monitored to optimize the performance of the ALS.
Date: June 13, 2001
Creator: Byrne, Warren E.; Lampo, Edward J. & Samuelson, Bruce C.
Partner: UNT Libraries Government Documents Department

Concentration of synchrotron beams by means of monolithic polycapillary x-ray optics

Description: Capillary Optics have proven to be a valuable tool for concentrating synchrotron radiation. Single tapered capillaries are used at several facilities. However, most of these optics collect only over a small area. this can be overcome by using larger capillary structures. Polycapillary optics can deflect x-rays by larger angles than other x-ray optics that use only one or two reflections. Conventional x-ray optics that achieve similar deflections, are much more energy selective than capillaries. Therefore, capillaries achieve very short focal distances for a wide range of energies. The measurements shown here represent first tests performed with polycapillaries of large input diameter. The performance with respect to transmission efficiency and spot size was evaluated for a set of four very different prototypes. It is shown that a significant gain may be achieved if a spot size of the order of 0.1 mm is required. Further, some characteristics of the different optics are discussed.
Date: August 1, 1995
Creator: Ullrich, J.B.; Klotzko, I.L.; Huang, K.G.; Owens, S.M.; Aloisi, D.C.; Hofmann, F.A. et al.
Partner: UNT Libraries Government Documents Department

Trapped modes in the PEP-II B-Factory Interaction Region

Description: The design of the PEP-II B-Factory Interaction Region is based primarily on beam-stay-clear requirements and on synchrotron radiation background considerations (masks are required to shield the detector beam pipe from all sources of synchrotron radiation). A complicated 3-dimensional structure results from these requirements. A high intensity beam traversing this structure will generate wake fields that lead to energy deposition on the beam pipe, as well as to decelerating and deflecting forces acting back on the beam. Computation of wake fields and impedances in frequency-domain and time-domain using 2-D and 3-D electromagnetic codes revealed the existence of trapped modes in the interaction region, which if not controlled could enhance the higher order model heating of the beam pipe. We will present the simulation results and the design strategy to avoid resonant conditions between these trapped modes and the bunch train frequency.
Date: April 1, 1995
Creator: Henestroza, E.; Heifets, S. & Zolotorev, M.
Partner: UNT Libraries Government Documents Department

Techniques for synchronization of X-Ray pulses to the pump laser in an ultrafast X-Ray facility

Description: Accurate timing of ultrafast x-ray probe pulses emitted from a synchrotron radiation source with respect to the signal initiating a process in the sample under study is critical for the investigation of structural dynamics in the femtosecond regime. We describe schemes for achieving accurate timing of femtosecond x-ray synchrotron radiation pulses relative to a pump laser, where x-rays pulses of &lt;100 fs duration are generated from the proposed LUX source based on a recirculating superconducting linac. We present a description of the timing signal generation and distribution systems to minimize timing jitter of the x-rays relative to the experimental lasers.
Date: May 6, 2003
Creator: Corlett, J.N.; Doolittle, L.; Schoenlein, R.; Staples, J.; Wilcox, R. & Zholents, A.
Partner: UNT Libraries Government Documents Department