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Sample records for advanced light sources

  1. Advanced light source

    NASA Astrophysics Data System (ADS)

    Sah, R. C.

    1983-03-01

    The Advanced Light Source (ALS) is a new synchrotron radiation source which was proposed by Lawrence Berkeley Laboratory. The ALS will be a key component in a major new research facility, the National Center for Advanced Materials. The ALS will consist of an electron linear accelerator, a booster synchrotron, a 1.3-GeV electron storage ring, and a number of photon beam lines. Most of all photon beam lines will originate from wiggler and undulator magnets placed in the 12 long straight sections of the ALS. A very low electron beam emittance will provide photon beams of unsurpassed spectral brilliance from specially-designed undulators, and a high radiofrequency will produce very short pulse lengths.

  2. Advanced Light Source elliptical wiggler

    NASA Astrophysics Data System (ADS)

    Hoyer, E.; Akre, J.; Humphries, D.; Marks, S.; Minamihara, Y.; Pipersky, P.; Plate, D.; Schlueter, R.

    1995-02-01

    A 3.5-m-long elliptical wiggler, optimized to produce elliptically polarized light in the 50 eV to 10 keV range, is currently under design and construction at the Advanced Light Source at Lawrence Berkeley Laboratory. Calculations of spectral performance show that the flux of circularly polarized photons exceeds 1013 photons/s over the 50 eV to 10 keV operating range for current of 0.4 A and 1.5 GeV electron energy. This device features vertical and horizontal magnetic structures of 14 and 141/2 periods, respectively. The period length is 20.0 cm. The vertical structure is a hybrid permanent magnet design with tapered pole tips that produce a peak field of 2.0 T. The horizontal structure is an iron core electromagnetic design, shifted longitudinally 1/4 period, that is tucked between the upper and lower vertical magnetic structure sections. A maximum peak oscillating field of 0.095 T at a frequency up to 1 Hz will be achieved by excitation of the horizontal poles with a trapezoidal current waveform. The vacuum chamber is an unconventional design that is removable from the magnetic structure, after magnetic measurements, for UHV processing. The chamber is fabricated from non-magnetic stainless steel to minimize the effects of eddy currents. Device design is presented.

  3. Advanced Light Source Activity Report 2000

    SciTech Connect

    Greiner, A.; Moxon, L.; Robinson, A.; Tamura, L.

    2001-04-01

    This is an annual report, detailing activities at the Advanced Light Source for the year 2000. It includes highlights of scientific research by users of the facility as well as information about the development of the facility itself.

  4. Advanced Light Source Activity Report 2002

    SciTech Connect

    Duque, Theresa; Greiner, Annette; Moxon, Elizabeth; Robinson, Arthur; Tamura, Lori

    2003-06-12

    This annual report of the Advanced Light Source details science highlights and facility improvements during the year. It also offers information on events sponsored by the facility, technical specifications, and staff and publication information.

  5. LIGHT SOURCE: Conceptual design of Hefei advanced light source

    NASA Astrophysics Data System (ADS)

    Li, Wei-Min; Wang, Lin; Feng, Guang-Yao; Zhang, Shan-Cai; Wu, Cong-Feng; Xu, Hong-Liang; Liu, Zu-Ping

    2009-06-01

    The conceptual of Hefei Advanced Light Source, which is an advanced VUV and Soft X-ray source, was developed at NSRL of USTC. According to the synchrotron radiation user requirements and the trends of SR source development, some accelerator-based schemes were considered and compared; furthermore storage ring with ultra low emittance was adopted as the baseline scheme of HALS. To achieve ultra low emittance, some focusing structures were studied and optimized in the lattice design. Compromising of emittance, on-momentum and off-momentum dynamic aperture and ring scale, five bend acromat (FBA) was employed. In the preliminary design of HALS, the emittance was reduced to sub nm · rad, thus the radiation up to water window has full lateral coherence. The brilliance of undulator radiation covering several eVs to keVs range is higher than that of HLS by several orders. The HALS should be one of the most advanced synchrotron radiation light sources in the world.

  6. The Advanced Light Source: Technical Design

    SciTech Connect

    Authors, Various

    1984-05-01

    The Advanced Light Source (ALS) is a synchrotron radiation source consisting of a 50-MeV linear accelerator, a 1.3-GeV 'booster' synchrotron, a 1.3-GeV electron storage ring, and a number of photon beam lines, as shown in Figure 1. As an introduction to a detailed description of the Advanced Light Source, this section provides brief discussions on the characteristics of synchrotron radiation and on the theory of storage rings. Appendix A contents: Introduction to Synchrotron-Radiation Sources; Storage Ring; Injection System; Control System; Insertion Devices; Photon Beam Lines; and References.

  7. Advanced controls for light sources

    NASA Astrophysics Data System (ADS)

    Biedron, S. G.; Edelen, A. L.; Milton, S. V.

    2016-09-01

    We present a summary of our team's recent efforts in developing adaptive, artificial intelligence-inspired techniques specifically to address several control challenges that arise in machines/systems including those in particle accelerator systems. These techniques can readily be adapted to other systems such as lasers, beamline optics, etc… We are not at all suggesting that we create an autonomous system, but create a system with an intelligent control system, that can continually use operational data to improve itself and combines both traditional and advanced techniques. We believe that the system performance and reliability can be increased based on our findings. Another related point is that the controls sub-system of an overall system is usually not the heart of the system architecture or design process. More bluntly, often times all of the peripheral systems are considered as secondary to the main system components in the architecture design process because it is assumed that the controls system will be able to "fix" challenges found later with the sub-systems for overall system operation. We will show that this is not always the case and that it took an intelligent control application to overcome a sub-system's challenges. We will provide a recent example of such a "fix" with a standard controller and with an artificial intelligence-inspired controller. A final related point to be covered is that of system adaptation for requirements not original to a system's original design.

  8. Monitoring performance of the Advanced Light Source

    SciTech Connect

    Byrne, Warren E.; Lampo, Edward J.; Samuelson, Bruce C.

    2001-06-13

    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.

  9. An Upgrade for the Advanced Light Source

    SciTech Connect

    Chemla, Daniel S.; Feinberg, Benedict; Hussain, Zahid; Kirz, Janos; Krebs, Gary F.; Padmore, Howard A.; Robin, David S.; Robinson, Arthur L.; Smith, Neville V.

    2004-09-01

    One of the first third-generation synchrotron light sources, the ALS, has been operating for almost a decade at Berkeley Lab, where experimenters have been exploiting its high brightness for forefront science. However, accelerator and insertion-device technology have significantly changed since the ALS was designed. As a result, the performance of the ALS is in danger of being eclipsed by that of newer, more advanced sources. The ALS upgrade that we are planning includes full-energy, top-off injection with higher storage-ring current and the replacement of five first-generation insertion devices with nine state-of-the art insertion devices and four new application-specific beamlines now being identified in a strategic planning process. The upgrade will help keep the ALS at the forefront of soft x-ray synchrotron light sources for the next two decades.

  10. Advanced Light Source beam diagnostics systems

    SciTech Connect

    Hinkson, J.

    1993-10-01

    The Advanced Light Source (ALS), a third-generation synchrotron light source, has been recently commissioned. Beam diagnostics were very important to the success of the operation. Each diagnostic system is described in this paper along with detailed discussion of its performance. Some of the systems have been in operation for two years. Others, in the storage ring, have not yet been fully commissioned. These systems were, however, working well enough to provide the essential information needed to store beam. The devices described in this paper include wall current monitors, a beam charge monitor, a 50 ohm Faraday cup, DC current transformers, broad-hand striplines, fluorescence screens, beam collimators and scrapers, and beam position monitors. Also, the means by which waveforms are digitized and displayed in the control room is discussed.

  11. Operator scheduling at the Advanced Light Source

    SciTech Connect

    Miller, B.

    1998-06-01

    Scheduling Operations staff at the Advanced Light Source (ALS) has evolved from 5 shifts/week for commissioning operations in 1992 to the present 24 hour/day, 21 shift coverage as the ALS went to full operation for users. A number of schedules were developed and implemented in an effort to accommodate changing ALS shift coverage requirements. The present work schedule and the lessons learned, address a number of issues that are useful to any facility that is operating 24 hours/day, 7 days/week.

  12. Scientific opportunities at the advanced light source

    NASA Astrophysics Data System (ADS)

    Robinson, A. L.

    1989-04-01

    The Advanced Light Source (ALS) is a national user facility for the production of high-brightness and partially coherent X-ray and ultraviolet synchrotron radiation. Now under construction at the Lawrence Berkeley Laboratory with a projected completion date of September 1992, the ALS is based on a low-emittance electron storage ring optimized for operation at 1.5 GeV with insertion devices in eleven long straight sections. It will also have up to 48 bending-magnet ports. Scientific opportunities in materials science, surface science, chemistry, atomic and molecular physics, life science and other fields are reflected in Letters of Interest received for the establishment of beamlines.

  13. Advanced Light Source beam position monitor

    SciTech Connect

    Hinkson, J.

    1991-10-28

    The Advanced Light Source (ALS) is a synchrotron radiation facility nearing completion at LBL. As a third-generation machine, the ALS is designed to produce intense light from bend magnets, wigglers, and undulators (insertion devices). The facility will include a 50 MeV electron linear accelerator, a 1.5 GeV booster synchrotron, beam transport lines, a 1--2 GeV storage ring, insertion devices, and photon beam lines. Currently, the beam injection systems are being commissioned, and the storage ring is being installed. Electron beam position monitors (BPM) are installed throughout the accelerator and constitute the major part of accelerator beam diagnostics. The design of the BPM instruments is complete, and 50 units have been constructed for use in the injector systems. We are currently fabricating 100 additional instruments for the storage ring. In this paper I discuss engineering fabrication, testing and performance of the beam pickup electrodes and the BPM electronics.

  14. Superbend upgrade on the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Robin, D.; Krupnick, J.; Schlueter, R.; Steier, C.; Marks, S.; Wang, B.; Zbasnik, J.; Benjegerdes, R.; Biocca, A.; Bish, P.; Brown, W.; Byrne, W.; Chen, J.; Decking, W.; DeVries, J.; DeMarco, W. R.; Fahmie, M.; Geyer, A.; Harkins, J.; Henderson, T.; Hinkson, J.; Hoyer, E.; Hull, D.; Jacobson, S.; McDonald, J.; Molinari, P.; Mueller, R.; Nadolski, L.; Nishimura, H.; Nishimura, K.; Ottens, F.; Paterson, J. A.; Pipersky, P.; Portmann, G.; Ritchie, A.; Rossi, S.; Salvant, B.; Scarvie, T.; Schmidt, A.; Spring, J.; Taylor, C.; Thur, W.; Timossi, C.; Wandesforde, A.

    2005-02-01

    The Advanced Light Source (ALS) is a third generation synchrotron light source at Lawrence Berkeley National Laboratory (LBNL). There was an increasing demand for additional high brightness hard X-ray beamlines in the 7-40 keV range, so in August 2001, three 1.3 T normal conducting bending magnets were removed from the storage ring and replaced with 5 T superconducting magnets (Superbends). The radiation produced by these Superbends is an order of magnitude higher in photon brightness and flux at 12 keV, making them excellent sources of hard X-rays for protein crystallography and other hard X-ray applications. The Superbends did not compromise the performance of the facility in the VUV and soft X-ray regions of the spectrum. The Superbends will eventually feed 12 new beam lines, greatly enhancing the facility's capability and capacity in the hard X-ray region. The Superbend project is the biggest upgrade since the ALS storage ring was commissioned in 1993. In this paper we present an overview of the Superbend project, its challenges and the resulting impact on the ALS.

  15. Advanced Light Source: Activity report 1993

    SciTech Connect

    Not Available

    1994-11-01

    The Advanced Light Source (ALS) produces the world`s brightest light in the ultraviolet and soft x-ray regions of the spectrum. The first low-energy third-generation synchrotron source in the world, the ALS provides unprecedented opportunities for research in science and technology not possible anywhere else. This year marked the beginning of operations and the start of the user research program at the ALS, which has already produced numerous high quality results. A national user facility located at Lawrence Berkeley Laboratory of the University of California, the ALS is available to researchers from academia, industry, and government laboratories. This report contains the following: (1) director`s message; (2) operations overview; (3) user program; (4) users` executive committee; (5) industrial outreach; (6) accelerator operations; (7) beamline control system; (8) insertion devices; (9) experimental systems; (10) beamline engineering; (11) first results from user beamlines; (12) beamlines for 1994--1995; (13) special events; (14) publications; (15) advisory panels; and (16) ALS staff.

  16. Status of the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Marx, Jay N.

    1991-01-01

    The Advanced Light Source (ALS) now under construction at the Lawrence Berkeley Laboratory will be a national user facility for the production ofhigh-brightness and partially coherent soft x-ray and ultraviolet synchrotron radiation. The ALS is based on a low-emittance electron storage ring optimized for operation at 1. 5 GeV with insertion devices in 10 long straight sections and 24 premier bend-magnet ports. High-brightness photon beams from less than 10 eV to more than 2 keY will be produced by undulators thereby providing many research opportunities in materials and surface science biology atomic physics and chemistry. Wigglers and bend magnets will provide high-flux broad-band radiation at energies to 10 keY. 2.

  17. Research opportunities at the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Robinson, A. L.; Schlachter, A. S.

    1991-05-01

    The Advanced Light Source (ALS), now under construction at the Lawrence Berkeley Laboratory, is a third-generation synchrotron radiation facility based on a low-emittance, 1.5-GeV electron storage ring with ten long straight sections available for insertion devices and, initially, 24 bend-magnet ports. Undulators will provide high-brightness radiation at photon energies from below 10 eV to above 2 keV; wiggler and bend-magnet radiation will extend the spectral coverage with high fluxes to above 10 keV. Scheduled to begin operations as a US Department of Energy national user facility in the spring of 1993, the ALS will support an extensive research program in which soft X-ray and ultraviolet radiation is used to study matter in all its varied gaseous, liquid and solid forms. Participating research teams to implement the initial scientific program have been selected.

  18. An ALS (Advanced Light Source) handbook

    SciTech Connect

    Not Available

    1988-11-01

    This booklet aims to provide the prospective user of the Advanced Light Source with a concise description of the radiation a researcher might expect at his or her experimental station. The focus is therefore on the characteristics of the light that emerges from insertion devices and bending magnets and on how components of the beam lines further alter the properties of the radiation. The specifications and operating parameters of the ALS injection system and storage ring are of only peripheral interest. To this end, Sections 3 and 5 and most of Section 4 are devoted to summary presentations, by means of performance plots and tabular compilations, of radiation characteristics at the ALS--spectral brightness, flux, coherent power, resolution, time structure, etc.--assuming a representative set of four undulators and one wiggler and a corresponding set of five beam lines. As a complement to these performance summaries, Section 1 is a general introductory discussion of synchrotron radiation and the ALS, and Section 2 provides a compendious introduction to the characteristics of synchrotron radiation from bending magnets, wigglers, and undulators. In addition, Section 4 briefly introduces the theory of diffraction grating and crystal monochromators. 15 refs., 28 figs., 5 tabs.

  19. Undulators at the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Hoyer, E.; Akre, J.; Chin, J.; Gath, W.; Hassenzahl, W. V.; Humphries, D.; Kincaid, B.; Marks, S.; Pipersky, P.; Plate, D.; Portmann, G.; Schlueter, R.

    1995-02-01

    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.

  20. Status report on the Advanced Light Source control system

    SciTech Connect

    Magyary, S.; Chin, M.; Fahmie, M.; Lancaster, H.; Molinari, P.; Robb, A.; Timossi, C.; Young, J.

    1991-11-11

    This paper is a status report on the ADVANCED LIGHT SOURCE (ALS) control system. The current status, performance data, and future plans will be discussed. Manpower, scheduling, and costs issues are addressed.

  1. Advanced light source, User`s Handbook, Revision 1

    SciTech Connect

    1995-07-01

    The Advanced Light Source (ALS) is a national facility for scientific research and development located at the Lawrence Berkeley National Laboratory (LBNL) of the University of California. Its purpose is to generate beams of very bright light in the ultraviolet and soft x-ray regions of the spectrum. The facility is open to researchers from industry, universities, and government laboratories.

  2. Survey, alignment, and beam stability at the Advanced Light Source

    SciTech Connect

    Krebs, G.F.

    1997-10-01

    This paper describes survey and alignment at the Lawrence Berkeley Laboratories Advanced Light Source (ALS) accelerators from 1993 to 1997. The ALS is a third generation light source requiring magnet alignment to within 150 microns. To accomplish this, a network of monuments was established and maintained. Monthly elevation surveys show the movement of the floor over time. Inclinometers have recently been employed to give real time information about magnet, vacuum tank and magnet girder motion in the ALS storage ring.

  3. Environmental Science Program at the Advanced Light Source

    SciTech Connect

    Nico, Peter; A; Anastasio, Cort; Dodge, Cleveland; Fendorf, Scott; Francis, A.J.; Hubbard, Susan; Shuh, David; Tomutsa, Liviu; Tufano, Kate; Tyliszczak, Tolek; Werner, Michelle; Williams, Ken

    2006-04-05

    The Advanced Light Source (ALS) has a variety of capabilities that are applicable to very different types of environmental systems. Shown are the basic descriptions of four of the approximately 35 beam lines at the ALS. The complimentary capabilities of these four beam lines allow for investigations that range from a spatial scale of a few nanometers to several millimeters. The Environmental Science Program at the Advanced Light Source seeks to promote and assist environmental research, particularly on the four beam lines described in this report. Several short examples of the types of research conducted on these beam lines are also described.

  4. Measurement of storage ring motion at the advanced light source

    SciTech Connect

    Krebs, G.F.

    1997-05-01

    The mechanical stability of the Advanced Light Source storage ring is examined over a period of 1.5 years from the point of view of floor motion. The storage ring beam position monitor stability is examined under various operating conditions.

  5. Advanced Light Source Activity Report 1997/1998

    SciTech Connect

    Greiner, Annette

    1999-03-01

    This Lawrence Berkeley National Laboratory, Advanced Light Source (ALS) activity report for 1997/98 discusses the following topics: Introduction and Overview; Science Highlights; Facility Report; Special Events; ALS Advisory Panels 1997/98; ALS Staff 1997/98 and Facts and Figures for the year.

  6. LIGHT SOURCE: Conceptual design of Hefei Advanced Light Source (HALS) injection system

    NASA Astrophysics Data System (ADS)

    Zhang, Shan-Cai; Wang, Lin; Feng, Guang-Yao; Wu, Cong-Feng; Li, Wei-Min; Xu, Hong-Liang; Liu, Zu-Ping

    2009-06-01

    The Hefei Advanced Light Source(HALS) is a super low emittance storage ring and has a very short beam life time. In order to run the ring stablely, top-up injection will be necessary. The injection system will greatly affect the quality of beam. This article first gives a physics design of the injecting system. Then the injecting system is tracked under different errors. The responses of storage beam and injecting beam are given in the article.

  7. Insertion devices for the Advanced Light Source at LBL

    SciTech Connect

    Hassenzahl, W.; Chin, J.; Halbach, K.; Hoyer, E.; Humphries, D.; Kincaid, B.; Savoy, R.

    1989-03-01

    The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory will be the first of the new generation of dedicated synchrotron light sources to be put into operation. Specially designed insertion devices will be required to realize the high brightness photon beams made possible by the low emittance of the electron beam. The complement of insertion devices on the ALS will include undulators with periods as short as 3.9 cm and one or more high field wigglers. The first device to be designed is a 5 m long, 5 cm period, hybrid undulator. The goal of very high brightness and high harmonic output imposes unusually tight tolerances on the magnetic field quality and thus on the mechanical structure. The design process, using a generic structure for all undulators, is described. 5 refs., 4 figs., 1 tab.

  8. The advanced light source at the Lawrence Berkeley laboratory

    NASA Astrophysics Data System (ADS)

    Jackson, Alan

    1991-05-01

    The Advanced Light Source (ALS), a national facility currently under construction at the Lawrence Berkeley Laboratory (LBL), is a third-generation synchrotron light source designed to produce extremely bright beams of synchrotron radiation, in the energy range from a few eV to 10 keV. The design is based on a 1-1.9 GeV electron storage ring (optimized at 1.5 GeV), and utilizes special magnets, known as undulators and wigglers (collectively referred to as insertion devices), to generate the radiation. In this paper we describe the main accelerator components of the ALS, the variety of insertion devices, the radiation spectra expected from these devices, and the complement of experiments that have been approved for initial operation, starting in April 1993.

  9. Status report on the Advanced Light Source control system, 1993

    SciTech Connect

    Young, J.; Brown, W. Jr.; Cork, C.

    1993-10-01

    The Advanced Light Source (ALS), under construction for the past seven years, has become operational. The accelerator has been successfully commissioned using a control system based on hundreds of controllers of our own design and high performance personal computers which are the operator interface. The first beamlines are being commissioned using a control system based on VME hardware and the Experimental Physics and Industrial Control System (EPICS) software. The two systems are being integrated, and this paper reports on the current work being done.

  10. The Advanced Light Source at Lawrence Berkeley Laboratory

    NASA Astrophysics Data System (ADS)

    Robinson, A. L.; Perera, R. C. C.; Schlachter, A. S.

    1992-01-01

    The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory (LBL), scheduled to be operational in the spring of 1993 as a U.S. Department of Energy national user facility, will be a next-generation source of soft x-ray and ultraviolet (XUV) synchrotron radiation. Undulators will provide the world's brightest synchrotron radiation at photon energies from below 10 eV to above 2 keV; wiggler and bend-magnet radiation will extend the spectral coverage with high fluxes above 10 keV. These capabilities will support an extensive research program in a broad spectrum of scientific and technological areas in which XUV radiation is used to study and manipulate matter in all its varied gaseous, liquid, and solid forms. The ALS will also serve those interested in developing the fabrication technology for microstructures and nanostructures, as well as for characterizing them.

  11. Design of the Advanced Light Source timing system

    SciTech Connect

    Fahmie, M.

    1993-05-01

    The Advanced Light Source (ALS) is a third generation synchrotron radiation facility, and as such, has several unique timing requirements. Arbitrary Storage Ring filling patterns and high single bunch purity requirements demand a highly stable, low jitter timing system with the flexibility to reconfigure on a pulse-to-pulse basis. This modular system utilizes a highly linear Gauss Clock with ``on the fly`` programmable setpoints to track a free-running Booster ramping magnet and provides digitally programmable sequencing and delay for Electron Gun, Linac, Booster Ring, and Storage Ring RF, Pulsed Magnet, and Instrumentation systems. It has proven itself over the last year of accelerator operation to be reliable and rock solid.

  12. Observations of collective effects at the Advanced Light Source

    SciTech Connect

    Byrd, J.M.; Barry, W.; Corlett, J.N.; Fox, J.; Teytelman, D.

    1995-10-01

    We present a summary of measurements of single beam collective effects in the Advanced Light Source (ALS). We describe measurements of coupled-bunch instabilities, including some recent results using the newly commissioned feedback systems and the results of an initial search for the fast ion instability. Single bunch effects include bunch lengthening, energy spread increase, HOM loss measurements, head-tail damping rates, current dependent tune shifts, and transverse mode coupling instability threshold. The longitudinal measurements are consistent with a broadband impedance {vert_bar}{Zeta}{sub {parallel}}/{eta}{vert_bar}{sub eff} = 0.22{plus_minus}0.07 {Omega} and transverse measurements indicate broadband impedances of {Zeta}{sub y,eff} = 155 k{Omega}/m and Z{sub x,eff} = 58 k{Omega}/m.

  13. Research opportunities in atomic physics at the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Schlachter, A. S.; Robinson, A. L.

    1989-09-01

    The Advanced Light Source (ALS) now under construction at the Lawrence Berkeley Laboratory is being planned as a national user facility for the production of high-brightness and partially coherent X-ray and ultraviolet synchrotron radiation. The ALS is based on a low-emittance electron storage ring optimized for operation at 1.5 GeV with insertion devices in 11 long straight sections and up to 48 bending-magnet ports. High-brightness photon beams from less than 10 eV to more than 1 keV will be produced by undulators, thereby providing many research opportunities in atomic and molecular physics and chemistry. Wigglers and bending magnets will provide high-flux broad-band radiation at energies to 10 keV.

  14. Performance of Advanced Light Source particle beam diagnostics

    SciTech Connect

    Hinkson, J.

    1993-05-01

    The Advanced Light Source (ALS), a third-generation synchrotron radiation facility, is complete. The particle beam diagnostics have been installed and tested. The beam injection systems have been running for two years. We have performance data on beam position monitors, beam intensity monitors, scintillators, beam collimators, a 50 {Omega} Faraday cup, and broad-band striplines and kickers used in the linac, transport lines, and the booster synchrotron. The single-turn monitoring capability of the booster beam position monitoring system has been particularly useful for studying beam dynamics. Beam diagnostics for the storage ring are being commissioned. In this paper we describe each instrument, show its performance, and outline how the instruments are controlled and their output data displayed.

  15. Scientific program of the advanced light source at LBL

    NASA Astrophysics Data System (ADS)

    Robinson, A. L.; Schlachter, A. S.

    1992-08-01

    Construction of the Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory is nearing completion, with operation as a US Department of Energy national user facility scheduled to begin in the spring of 1993. Based on a low-emittance, 1.5 GeV electron storage ring with ten long straight sections available for insertion devices and, initially, 24 bend-magnet ports, the ALS will be a third-generation source of soft X-ray and ultraviolet (collectively, the XUV) synchrotron radiation. Experimental facilities (insertion devices, beamlines, and end stations) will be developed and operated by participating research teams working with the ALS staff. The ability to exploit the high spectral brightness of the ALS was the main criterion for PRT selection. In the XUV spectral regions served by the ALS, a major benefit of high brightness will be the ability to achieve spatial resolution in the neighborhood of 200 Å in X-ray microscopy and holography and in spatially resolved spectroscopy. Other beneficiaries of high brightness include very-high-resolution spectroscopy, spectroscopy of dilute species, diffraction from very small samples, and time-resolved spectroscopy and diffraction.

  16. Science at the Speed of Light: Advanced Photon Source

    SciTech Connect

    Murray Gibson

    2009-06-03

    An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest x-ray beams in the Western Hemisphere, and the research carried out by scientists using those x-rays.

  17. Science at the Speed of Light: Advanced Photon Source

    ScienceCinema

    Murray Gibson

    2016-07-12

    An introduction and overview of the Advanced Photon Source at Argonne National Laboratory, the technology that produces the brightest x-ray beams in the Western Hemisphere, and the research carried out by scientists using those x-rays.

  18. The advanced light source: America`s brightest light for science and industry

    SciTech Connect

    Cross, J.; Lawler, G.

    1994-03-01

    America`s brightest light comes from the Advanced Light Source (ALS), a national facility for scientific research, product development, and manufacturing. Completed in 1993, the ALS produces light in the ultraviolet and x-ray regions of the spectrum. Its extreme brightness provides opportunities for scientific and technical progress not possible anywhere else. Technology is poised on the brink of a major revolution - one in which vital machine components and industrial processes will be drastically miniaturized. Industrialized nations are vying for leadership in this revolution - and the huge economic rewards the leaders will reap.

  19. Water cooled metal optics for the Advanced Light Source

    SciTech Connect

    McKinney, W.R.; Irick, S.C.; Lunt, D.L.J.

    1991-10-28

    The program for providing water cooled metal optics for the Advanced Light Source at Berkeley is reviewed with respect to fabrication and metrology of the surfaces. Materials choices, surface figure and smoothness specifications, and metrology systems for measuring the plated metal surfaces are discussed. Results from prototype mirrors and grating blanks will be presented, which show exceptionally low microroughness and mid-period error. We will briefly describe out improved version of the Long Trace Profiler, and its importance to out metrology program. We have completely redesigned the mechanical, optical and computational parts of the profiler system with the cooperation of Peter Takacs of Brookhaven, Continental Optical, and Baker Manufacturing. Most important is that one of our profilers is in use at the vendor to allow testing during fabrication. Metrology from the first water cooled mirror for an ALS beamline is presented as an example. The preplating processing and grinding and polishing were done by Tucson Optical. We will show significantly better surface microroughness on electroless nickel, over large areas, than has been reported previously.

  20. EDITORIAL: Special Issue on advanced and emerging light sources Special Issue on advanced and emerging light sources

    NASA Astrophysics Data System (ADS)

    Haverlag, Marco; Kroesen, Gerrit; Ferguson, Ian

    2011-06-01

    -based light sources. However, the progress in the last few years in LED and OLED sources has been even greater. In the editorial for the LS-11 conference by previous guest editor David Wharmby, it was stated that most LED lighting was still mostly used for signalling and decorative sources. In the three years that have passed, things have changed considerably and we now see LED light sources entering every application, ranging from street lighting and parking lots to shop lighting and even greenhouses. Currently LED prices for traditional lighting applications are high, but they are dropping rapidly. The papers published in this special issue give some indications of things to come. The paper by Jamil et al deals with the possibility of using silicon wafers as substrate material instead of the now commonly used (but more expensive) sapphire substrates. This is attractive from a cost price point of view, but leads to an increased lattice mismatch and therefore strain-induced defects. In this paper it is shown that when using intermediate matching layers it is possible to retain the same electrical and optical properties as with structures on sapphire. Another aspect that directly relates to cost is efficiency and droop in green InGaN devices, which is addressed in the paper by Lee et al. They show that by providing a flow of trymethylindium prior to the growth of the quantum wells it is possible to significantly increase the internal quantum efficiency of green LEDs. Improvement of the optical out-coupling of InGaN LEDs is discussed by Mak et al, and it is found that localized plasmon resonance of metallic nanoparticles (and especially silver) can help to increase the optical out-coupling in the wavelength region of interest. Nanoparticles in the form of ZnO nanorods are described by Willander et al as a possibility for phosphor-free wavelength conversion on polymer (O)LEDs. More advanced functions besides light emission can be achieved with OLEDs and this is demonstrated in

  1. Advanced Light Source activity report 1996/97

    SciTech Connect

    1997-09-01

    Ten years ago, the Advanced Light Source (ALS) existed as a set of drawings, calculations, and ideas. Four years ago, it stored an electron beam for the first time. Today, the ALS has moved from those ideas and beginnings to a robust, third-generation synchrotron user facility, with eighteen beam lines in use, many more in planning or construction phases, and hundreds of users from around the world. Progress from concepts to realities is continuous as the scientific program, already strong in many diverse areas, moves in new directions to meet the needs of researchers into the next century. ALS staff members who develop and maintain the infrastructure for this research are similarly unwilling to rest on their laurels. As a result, the quality of the photon beams the authors deliver, as well as the support they provide to users, continues to improve. The ALS Activity Report is designed to share the results of these efforts in an accessible form for a broad audience. The Scientific Program section, while not comprehensive, shares the breadth, variety, and interest of recent research at the ALS. (The Compendium of User Abstracts and Technical Reports provides a more comprehensive and more technical view.) The Facility Report highlights progress in operations, ongoing accelerator research and development, and beamline instrumentation efforts. Although these Activity Report sections are separate, in practice the achievements of staff and users at the ALS are inseparable. User-staff collaboration is essential as they strive to meet the needs of the user community and to continue the ALS's success as a premier research facility.

  2. The Advanced Light Source: A third-generation Synchrotron Radiation Source

    SciTech Connect

    Robinson, Arthur L.

    2002-08-14

    The Advanced Light Source (ALS) at the E.O. Lawrence Berkeley National Laboratory (Berkeley Lab) of the University of California is a ''third-generation'' synchrotron radiation source optimized for highest brightness at ultraviolet and soft x-ray photon energies. It also provides world-class performance at hard x-ray photon energies. Berkeley Lab operates the ALS for the United States Department of Energy as a national user facility that is available 24 hours/day around the year for research by scientists from industrial, academic, and government laboratories primarily from the United States but also from abroad.

  3. Imaging spectroscopic analysis at the Advanced Light Source

    SciTech Connect

    MacDowell, A. A.; Warwick, T.; Anders, S.; Lamble, G.M.; Martin, M.C.; McKinney, W.R.; Padmore, H.A.

    1999-05-12

    One of the major advances at the high brightness third generation synchrotrons is the dramatic improvement of imaging capability. There is a large multi-disciplinary effort underway at the ALS to develop imaging X-ray, UV and Infra-red spectroscopic analysis on a spatial scale from. a few microns to 10nm. These developments make use of light that varies in energy from 6meV to 15KeV. Imaging and spectroscopy are finding applications in surface science, bulk materials analysis, semiconductor structures, particulate contaminants, magnetic thin films, biology and environmental science. This article is an overview and status report from the developers of some of these techniques at the ALS. The following table lists all the currently available microscopes at the. ALS. This article will describe some of the microscopes and some of the early applications.

  4. X-ray micro-Tomography at the Advanced Light Source

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The X-ray micro-Tomography Facility at the Advanced Light Source has been in operation since 2004. The source is a superconducting bend magnet of critical energy 10.5KeV; photon energy coverage is 8-45 KeV in monochromatic mode, and a filtered white light option yields useful photons up to 50 KeV. A...

  5. Single-layer mirrors for advanced research light sources

    NASA Astrophysics Data System (ADS)

    Störmer, M.; Horstmann, C.; Siewert, F.; Scholze, F.; Krumrey, M.; Hertlein, F.; Matiaske, M.; Wiesmann, J.; Gaudin, J.

    2010-06-01

    X-ray mirrors are needed for beam guidance, beam alignment and monochromatisation at third-generation synchrotron light sources (PETRA III) and forthcoming Free-Electron Lasers (LCLS, European XFEL). Amorphous carbon coatings are currently used as total reflection mirrors at FLASH to guide the photon beam to the various beamlines. These coatings were prepared by means of magnetron sputtering. The new GKSS sputtering facility for the deposition of single and multilayer mirrors with a length of up to 1500 mm and a width of up to 120 mm is in operation. In this contribution we present the results of this new deposition system. A major advantage is that it is now possible to prepare one, two or more mirrors with similar properties over the whole deposition length. The mirror properties were investigated by means of X-ray reflectometry and interference microscopy. The performance of the mirrors is analyzed, considering X-ray reflectivity, film thickness and surface roughness. The uniformity of these properties over the whole deposition length of 1500 mm is demonstrated. The results obtained will be discussed and compared with former results.

  6. Single-layer mirrors for advanced research light sources

    SciTech Connect

    Stoermer, M.; Horstmann, C.; Siewert, F.; Hertlein, F.; Matiaske, M.; Wiesmann, J.; Gaudin, J.

    2010-06-23

    X-ray mirrors are needed for beam guidance, beam alignment and monochromatisation at third-generation synchrotron light sources (PETRA III) and forthcoming Free-Electron Lasers (LCLS, European XFEL). Amorphous carbon coatings are currently used as total reflection mirrors at FLASH to guide the photon beam to the various beamlines. These coatings were prepared by means of magnetron sputtering. The new GKSS sputtering facility for the deposition of single and multilayer mirrors with a length of up to 1500 mm and a width of up to 120 mm is in operation. In this contribution we present the results of this new deposition system. A major advantage is that it is now possible to prepare one, two or more mirrors with similar properties over the whole deposition length. The mirror properties were investigated by means of X-ray reflectometry and interference microscopy. The performance of the mirrors is analyzed, considering X-ray reflectivity, film thickness and surface roughness. The uniformity of these properties over the whole deposition length of 1500 mm is demonstrated. The results obtained will be discussed and compared with former results.

  7. Vacuum system for the LBL Advanced Light Source (ALS)

    SciTech Connect

    Kennedy, K.; Henderson, T.; Meneghetti, J. )

    1989-03-01

    A 1.5 to 1.9 GeV synchrotron light source is being built at LBL. The vacuum system is designed to permit most synchrotron photons to escape the electron channel and be absorbed in an antechamber. The gas generated by the photons hitting the absorbers in the antechambers will be pumped by titanium sublimation pumps located directly under the absorbers. The electron channel and the antechamber are connected by a 10-mm-high slot that offers good electrodynamic isolation of the two chambers of frequencies affecting the store electron orbit. Twelve 10-meter-long vessels constitute the vacuum chambers for all the lattice magnets. Each chamber will be machined from two thick plates of 5083-H321 aluminum and welded at the perimeter. Machining both the inside and outside of the vacuum chamber permits the use of complex and accurate surfaces. The use of thick plates allows flanges to be machined directly into the wall of each chamber, thus avoiding much welding. 1 ref., 3 figs.

  8. Advanced light source at Lawrence Berkeley Laboratory (invited)

    NASA Astrophysics Data System (ADS)

    Cornacchia, M.

    1989-07-01

    The 1-2-GeV synchrotron radiation source will be a national user-based facility providing photon beams of unprecedented brightness in the ultraviolet and soft x-ray region of the electromagnetic spectrum. The facility design is optimized to emphasize the use of undulators to provide high-spectral brilliance in the few electron volt to 1-keV spectral range; wigglers provide high flux up to approximately 10 keV. Beam structure of a few tens of picoseconds will be available for time-resolved experiments. The facility is designed for operational flexibility and to assure rapid commissioning. The initial complement of experimental stations consists of five insertion devices (four undulators and our wiggler) and associated beamlines, and two white light beams from bend magnets. Six other straight sections are available for additional insertion devices, and the design provides for up to 48 ports for beams from bending magnets. The storage ring is optimized for operation at 1.5 GeV with a maximum energy of 1.9 GeV. The injection system includes a 1-Hz, 1.5-GeV booster synchrotron for full energy injection at the nominal operating energy of the storage ring. Filling time for the maximum stored current of 400 mA is expected to be 2 min, and the beam half-life will be about 6 h. Attention is being given to the severe requirements for beam stability and the need to independently control photon beam alignment. We describe the important characteristics of the facility, significant aspects of the technical design of accelerator systems, insertion devices and photon beamlines, and considerations related to addressing projected user needs in the development of the project.

  9. Annual meeting of the Advanced Light Source Users` Association

    SciTech Connect

    1995-02-01

    This report contains papers on the following topics: ALS Director`s Report; ALS Operations Update; Recent Results in Machine Physics; Progress in Beamline Commissioning and Overview of New Projects; The ALS Scientific Program; First Results from the SpectroMicroscopy Beamline; Soft X-ray Fluorescence Spectroscopy of Solids; Soft X-Ray Fluorescence Spectroscopy of Molecules; Microstructures and Micromachining at the ALS; High-Resolution Photoemission from Simple Atoms and Molecules; X-Ray Diffraction at the ALS; Utilizing Synchrotron Radiation in Advanced Materials Industries; Polymer Microscopy: About Balls, Rocks and Other ``Stuff``; Infrared Research and Applications; and ALS User Program.

  10. Advanced Light Source report. Volume 7, No. 1

    SciTech Connect

    Not Available

    1994-09-01

    The exceptional science already emerging from the user program at the ALS shows that the promises of ``unique research opportunities`` and ``experiments not possible anywhere else`` made at the inception of the ALS are indeed coming true. In less than a year of beamline operations, the ALS has produced numerous high-quality results and achieved an enviable level of performance. Since the beginning of 1994, the ALS has operated for 92% of its scheduled hours, an outstanding achievement for a new machine. The ALS` ability to deliver the brightest light in the world in the ultraviolet and soft x-ray regions of the spectrum has attracted a who`s who of synchrotron research to the experiment floor. These users have produced a variety of scientifically significant results during the ALS` first year of operation, a few of which are highlighted in this article.

  11. Light Source

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Research on food growth for long duration spacecraft has resulted in a light source for growing plants indoors known as Qbeam, a solid state light source consisting of a control unit and lamp. The light source, manufactured by Quantum Devices, Inc., is not very hot, although it generates high intensity radiation. When Ron Ignatius, an industrial partner of WCSAR, realized that terrestrial plant research lighting was not energy efficient enough for space use, he and WCSAR began to experiment with light emitting diodes. A line of LED products was developed, and QDI was formed to market the technology. An LED-based cancer treatment device is currently under development.

  12. Advanced Light Source First-Phase Scientific Program, 1993/1994

    SciTech Connect

    Not Available

    1992-08-01

    This composite document outlines ten different experiments planned for the beamline at the Advanced Light Source. Researchers from various parts of the country have detailed their methods and equipment to be used in experiments in biology and physics. X-ray spectroscopy and microscopy are the common topics to these experiments. (GHH)

  13. High-resolution VUV spectroscopy: New results from the Advanced Light Source

    SciTech Connect

    Schlachter, F.; Bozek, J.

    1996-06-01

    Third-generation synchrotron light sources are providing photon beams of unprecedented brightness for researchers in atomic and molecular physics. Beamline 9.0.1, an undulator beamline at the Advanced Light Source (ALS), produces a beam in the vacuum-ultraviolet (VUV) region of the spectrum with exceptional flux and spectral resolution. Exciting new results from experiments in atomic and molecular VUV spectroscopy of doubly excited autoionizing states of helium, hollow lithium, and photoelectron spectroscopy of small molecules using Beamline 9.0.1 at the ALS are reported.

  14. Thermophysical properties of saturated light and heavy water for Advanced Neutron Source applications

    SciTech Connect

    Crabtree, A.; Siman-Tov, M.

    1993-05-01

    The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor`s nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300{degrees}C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250{degrees}C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

  15. Thermophysical properties of saturated light and heavy water for advanced neutron source applications

    SciTech Connect

    Crabtree, A.; Siman-Tov, M.

    1993-05-01

    The Advanced Neutron Source is an experimental facility being developed by Oak Ridge National Laboratory. As a new nuclear fission research reactor of unprecedented flux, the Advanced Neutron Source Reactor will provide the most intense steady-state beams of neutrons in the world. The high heat fluxes generated in the reactor [303 MW(t) with an average power density of 4.5 MW/L] will be accommodated by a flow of heavy water through the core at high velocities. In support of this experimental and analytical effort, a reliable, highly accurate, and uniform source of thermodynamic and transport property correlations for saturated light and heavy water were developed. In order to attain high accuracy in the correlations, the range of these correlations was limited to the proposed Advanced Neutron Source Reactor's nominal operating conditions. The temperature and corresponding saturation pressure ranges used for light water were 20--300[degrees]C and 0.0025--8.5 MPa, respectively, while those for heavy water were 50--250[degrees]C and 0.012--3.9 MPa. Deviations between the correlation predictions and data from the various sources did not exceed 1.0%. Light water vapor density was the only exception, with an error of 1.76%. The physical property package consists of analytical correlations, SAS codes, and FORTRAN subroutines incorporating these correlations, as well as an interactive, easy-to-use program entitled QuikProp.

  16. RECENT BEAM MEASUREMENTS AND NEW INSTRUMENTATION AT THE ADVANCED LIGHT SOURCE

    SciTech Connect

    Sannibale, Fernando; Baptiste, Kenneth; Barry, Walter; Chin, Michael; Filippetto, Daniele; Jaegerhofer, Lukas; Julian, James; Kwiatkowski, Slawomir; Low, Raymond; Plate, David; Portmann, Gregory; Robin, David; Scarvie, Tomas; Stupakov, Gennady; Weber, Jonah; Zolotorev, Max

    2008-05-05

    The Advanced Light Source (ALS) in Berkeley was the first of the soft x-ray third generation light source ever built, and since 1993 has been in continuous and successful operation serving a large community of users in the VUV and soft x-ray community. During these years the storage ring underwent through several important upgrades that allowed maintaining the performance of this veteran facility at the forefront. The ALS beam diagnostics and instrumentation have followed a similar path of innovation and upgrade and nowadays include most of the modem and last generation devices and technologies that are commercially available and used in the recently constructed third generation light sources. In this paper we will not focus on such already widely known systems, but we will concentrate our effort in the description of some measurements techniques, instrumentation and diagnostic systems specifically developed at the ALS and used during the last few years.

  17. Recent Beam Measurements and New Instrumentation at the Advanced Light Source

    SciTech Connect

    Sannibale, F.; Baptiste, K.; Barry, W.; Chin, M.; Filippetto, D.; Jaegerhofer, L.; Julian, J.; Kwiatkowski, S.; Low, R.; Plate, D.; Portmann, G.; Robin, D.; Scarvie, T.; Stupakov, G.; Weber, J.; Zolotorev, M.; /LBL, Berkeley

    2012-04-11

    The Advanced Light Source (ALS) in Berkeley was the first of the soft x-ray third generation light source ever built, and since 1993 has been in continuous and successful operation serving a large community of users in the VUV and soft x-ray community. During these years the storage ring underwent through several important upgrades that allowed maintaining the performance of this veteran facility at the forefront. The ALS beam diagnostics and instrumentation have followed a similar path of innovation and upgrade and nowadays include most of the modem and last generation devices and technologies that are commercially available and used in the recently constructed third generation light sources. In this paper we will not focus on such already widely known systems, but we will concentrate our effort in the description of some measurements techniques, instrumentation and diagnostic systems specifically developed at the ALS and used during the last few years.

  18. First commissioning results for the elliptically polarizing undulator beamline at the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Young, A. T.; Feng, J.; Arenholz, E.; Padmore, H. A.; Henderson, T.; Marks, S.; Hoyer, E.; Schlueter, R.; Kortright, J. B.; Martynov, V.; Steier, C.; Portmann, G.

    2001-07-01

    A new facility at the Advanced Light Source, Lawrence Berkeley National Laboratory, for high resolution magnetic spectroscopy is described. Beamline 4.0.2 has an elliptically polarizing undulator (EPU) and a high resolution monochromator, covering the energy range from 90 to 1800 eV. In this paper, we present the first commissioning results from this beamline, including measurements of the spectral resolution, photon flux and polarization of the x-rays.

  19. Development of a microsecond X-ray protein footprinting facility at the Advanced Light Source

    PubMed Central

    Gupta, Sayan; Celestre, Richard; Petzold, Christopher J.; Chance, Mark R.; Ralston, Corie

    2014-01-01

    X-ray footprinting (XF) is an important structural biology tool used to determine macromolecular conformations and dynamics of both nucleic acids and proteins in solution on a wide range of timescales. With the impending shut-down of the National Synchrotron Light Source, it is ever more important that this tool continues to be developed at other synchrotron facilities to accommodate XF users. Toward this end, a collaborative XF program has been initiated at the Advanced Light Source using the white-light bending-magnet beamlines 5.3.1 and 3.2.1. Accessibility of the microsecond time regime for protein footprinting is demonstrated at beamline 5.3.1 using the high flux density provided by a focusing mirror in combination with a micro-capillary flow cell. It is further reported that, by saturating samples with nitrous oxide, the radiolytic labeling efficiency is increased and the imprints of bound versus bulk water can be distinguished. These results both demonstrate the suitability of the Advanced Light Source as a second home for the XF experiment, and pave the way for obtaining high-quality structural data on complex protein samples and dynamics information on the microsecond timescale. PMID:24971962

  20. The Advanced Light Source: A new tool for research in atomic and molecular physics

    NASA Astrophysics Data System (ADS)

    Schlachter, F.; Robinson, A.

    1991-04-01

    The Advanced Light Source at the Lawrence Berkeley Laboratory will be the world's brightest synchrotron radiation source in the extreme ultraviolet and soft x-ray regions of the spectrum when it begins operation in 1993. It will be available as a national user facility to researchers in a broad range of disciplines, including materials science, atomic and molecular physics, chemistry, biology, imaging, and technology. The high brightness of the ALS will be particularly well suited to high-resolution studies of tenuous targets, such as excited atoms, ions, and clusters.

  1. Analysis of insertion device magnet measurements for the Advanced Light Source

    SciTech Connect

    Marks, S.; Humphries, D.; Kincaid, B.M.; Schlueter, R.; Wang, C.

    1993-07-01

    The Advanced Light Source (ALS), which is currently being commissioned at Lawrence Berkeley Laboratory, is a third generation light source designed to produce XUV radiation of unprecedented brightness. To meet the high brightness goal the storage ring has been designed for very small electron beam emittance and the undulators installed in the ALS are built to a high degree of precision. The allowable magnetic field errors are driven by electron beam and radiation requirements. Detailed magnetic measurements and adjustments are performed on each undulator to qualify it for installation in the ALS. The first two ALS undulators, IDA and IDB, have been installed. This paper describes the program of measurements, data analysis, and adjustments carried out for these two devices. Calculations of the radiation spectrum, based upon magnetic measurements, are included. Final field integral distributions are also shown. Good field integral uniformity has been achieved using a novel correction scheme, which is also described.

  2. Analysis of insertion device magnet measurements for the advanced light source

    NASA Astrophysics Data System (ADS)

    Marks, Steve; Humphries, David E.; Kincaid, Brian M.; Schlueter, Ross D.; Wang, Chunxi

    1993-11-01

    The Advanced Light Source (ALS), which is currently being commissioned at Lawrence Berkeley Laboratory, is a third generation light source designed to produce XUV radiation of unprecedented brightness. To meet the high brightness goal the storage ring has been designed for very small electron beam emittance and the undulators installed in the ALS are built to a high degree of precision. The allowable magnetic field errors are driven by electron beam and radiation requirements. Detailed magnetic measurements and adjustments are performed on each undulator to qualify it for installation in the ALS. The first two ALS undulators, IDA and IDB, have been installed. This paper describes the program of measurements, data analysis, and adjustments carried out for these two devices. Calculations of the radiation spectrum, based upon magnetic measurements, are included. Final field integral distributions are also shown. Good field integral uniformity has been achieved using a novel correction scheme, which is also described.

  3. The Advanced Light Source at the Lawrence Berkeley Laboratory (ALS, LBL)

    SciTech Connect

    Jackson, A.

    1990-08-01

    The Advanced Light Source (ALS), a national facility currently under construction at the Lawrence Berkeley Laboratory (LBL), is a third-generation synchrotron light source designed to produce extremely bright beams of synchrotron radiation, in the energy range from a few eV to 10 keV. The design is based on a 1-1.9 GeV electron storage ring (optimized at 1.5 GeV), and utilizes special magnets, known as undulators and wigglers (collectively referred to as insertion devices), to generate the radiation. In this paper we describe the main accelerator components of the ALS, the variety of insertion devices, the radiation spectra expected from these devices, and the complement of experiments that have been approved for initial operation, starting in April 1993.

  4. Advanced light ion source extraction system for a new electron cyclotron resonance ion source geometry at Saclay.

    PubMed

    Delferrière, O; Gobin, R; Harrault, F; Nyckees, S; Sauce, Y; Tuske, O

    2012-02-01

    One of the main goal of intense light ion injector projects such as IPHI, IFMIF, or SPIRAL2, is to produce high current beams while keeping transverse emittance as low as possible. To prevent emittance growth induced in a dual solenoid low energy transfer line, its length has to be minimized. This can be performed with the advanced light ion source extraction system concept that we are developing: a new ECR 2.45 GHz type ion source based on the use of an additional low energy beam transport (LEBT) short length solenoid close to the extraction aperture to create the resonance in the plasma chamber. The geometry of the source has been considerably modified to allow easy maintenance of each component and to save space in front of the extraction. The source aims to be very flexible and to be able to extract high current ion beams at energy up to 100 kV. A specific experimental setup for this source is under installation on the BETSI test bench, to compare its performances with sources developed up to now in the laboratory, such as SILHI, IFMIF, or SPIRAL2 ECR sources. This original extraction source concept is presented, as well as electromagnetic simulations with OPERA-2D code. Ion beam extraction in space charge compensation regime with AXCEL, and beam dynamics simulation with SOLMAXP codes show the beam quality improvement at the end of the LEBT.

  5. Advanced light ion source extraction system for a new electron cyclotron resonance ion source geometry at Saclaya)

    NASA Astrophysics Data System (ADS)

    Delferrière, O.; Gobin, R.; Harrault, F.; Nyckees, S.; Sauce, Y.; Tuske, O.

    2012-02-01

    One of the main goal of intense light ion injector projects such as IPHI, IFMIF, or SPIRAL2, is to produce high current beams while keeping transverse emittance as low as possible. To prevent emittance growth induced in a dual solenoid low energy transfer line, its length has to be minimized. This can be performed with the advanced light ion source extraction system concept that we are developing: a new ECR 2.45 GHz type ion source based on the use of an additional low energy beam transport (LEBT) short length solenoid close to the extraction aperture to create the resonance in the plasma chamber. The geometry of the source has been considerably modified to allow easy maintenance of each component and to save space in front of the extraction. The source aims to be very flexible and to be able to extract high current ion beams at energy up to 100 kV. A specific experimental setup for this source is under installation on the BETSI test bench, to compare its performances with sources developed up to now in the laboratory, such as SILHI, IFMIF, or SPIRAL2 ECR sources. This original extraction source concept is presented, as well as electromagnetic simulations with OPERA-2D code. Ion beam extraction in space charge compensation regime with AXCEL, and beam dynamics simulation with SOLMAXP codes show the beam quality improvement at the end of the LEBT.

  6. Realizing the benefits of restored periodicity in the advanced light source

    NASA Astrophysics Data System (ADS)

    Robin, D.; Safranek, J.; Decking, W.

    1999-04-01

    An essential feature of third generation storage ring based light sources is the magnetic lattice is designed with a high degree of periodicity. Tracking simulations show that if the periodicity is perturbed (by focusing errors, for example), nonlinear resonances become excited, which causes a reduction in the dynamic aperture. Therefore it is important to have a method to measure and correct perturbed periodicity. In this paper we study the effect of broken and restored periodicity at an actual third generation light source: the Advanced Light Source at Lawrence Berkeley National Laboratory. First, we show that it is possible to accurately determine the storage ring optic and thus the perturbation of the periodicity by fitting measured orbit response matrices. This method allows us to determine individual field gradient errors in quadrupoles and closed orbit errors in sextupoles. By varying individual quadrupole field strengths it is possible to correct the optic, largely restoring the lattice periodicity. A comparison is made of the performance of the storage ring before and after the optic is corrected. Measurements of the electron beam tails and the synchrotron light image reveal a large suppression in resonance excitation after the optic is corrected. Correcting the optic also improves the injection efficiency.

  7. Enhanced Performance of the Advanced Light Source through Periodicity Restoration of the Linear Lattice

    NASA Astrophysics Data System (ADS)

    Robin, D.; Steier, C.; Safranek, J.; Decking, W.

    2002-01-01

    An essential feature of third generation storage ring based light sources is the magnetic lattice is designed with a high degree of periodicity. Tracking simulations show that if the periodicity is perturbed (by focusing errors for example), non-linear resonances become excited, which causes a reduction in the dynamic aperture. Therefore it is important to have a method to measure and correct perturbed periodicity. In this paper we study the effect of broken and restored periodicity at an actual third generation light source: the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory. First we show that it is possible to accurately determine the storage ring optic and thus the perturbation of the periodicity by fitting measured orbit response matrices. This method allows us to determine individual field gradient errors in quadrupoles and closed orbit errors in sextupoles. By varying individual quadrupole field strengths it is possible to correct the optic, largely restoring the lattice periodicity. A comparison is made of the performance of the ALS before and after the optic is corrected. Measurements of the electron beam tails and the synchrotron light image reveal a large suppression in resonance excitation after the optic is corrected. Correcting the optic also improves the injection efficiency and lifetime.

  8. Measurement of the Radiation Incident on NbFeB Insertion Devices at the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Krebs, Gary; Holmes, Michael

    1997-05-01

    The Lawrence Berkeley National Laboratories Advanced Light Source is a third generation light source containing NdFeB permanent magnet insertion devices.The lifetime of the permanent magnets in a radiation environment is of paramount importance. Measurements of the radiation incident on the insertion device magnets under various operating conditions are presented.

  9. Advanced Light Source Compendium of User Abstracts andTechnical Reports 1997

    SciTech Connect

    Cross, J.; Devereaux, M.K.; Dixon, D.J.; Greiner, A.; editors

    1998-07-01

    The Advanced Light Source (ALS), a national user facility located at Ernest Orlando Lawrence Berkeley National Laboratory of the University of California is available to researchers from academia, industry, and government laboratories. Operation of the ALS is funded by the Department of Energy's Office of Basic Energy Sciences. This Compendium contains abstracts written by users summarizing research completed or in progress during 1997, ALS technical reports describing ongoing efforts related to improvement in machine operations and research and development projects, and information on ALS beamlines planned through 1998.

  10. Fabrication and test of prototype ring magnets for the ALS (Advanced Light Source)

    SciTech Connect

    Tanabe, J.; Avery, R.; Caylor, R.; Green, M.I.; Hoyer, E.; Halbach, K.; Hernandez, S.; Humphries, D.; Kajiyama, Y.; Keller, R.; Low, W.; Marks, S.; Milburn, J.; Yee, D.

    1989-03-01

    Prototype Models for the Advanced Light Source (ALS) Booster Dipole, Quadrupole and Sextupole and the Storage Ring Gradient Magnet, Quadrupole and Sextupole have been constructed. The Booster Magnet Prototypes have been tested. The Storage Ring Magnets are presently undergoing tests and magnetic measurements. This paper reviews the designs and parameters for these magnets, briefly describes features of the magnet designs which respond to the special constraints imposed by the requirements for both accelerator rings, and reviews some of the results of magnet measurements for the prototype. 13 refs., 7 figs., 1 tab.

  11. A directly cooled grating substrate for ALS (Advanced Light Source) undulator beam lines

    SciTech Connect

    DiGennaro, R.; Swain, T.

    1989-08-01

    Design analyses using finite element methods are presented for thermal distortion of water-cooled diffraction grating substrates for a potential application at the LBL Advanced Light Source, demonstrating that refinements in cooling channel configuration and heat flux distribution can significantly reduce optical surface distortion with high heat loads. Using an existing grating substrate design, sensitivity of tangential slope errors due to thermal distortion is evaluated for a variety of thermal boundary conditions, including coolant flow rate and heat transfer film coefficients, surface illumination area and heat distribution profile, and location of the convection cooling surfaces adjacent to the heated region. 1 ref., 5 figs., 2 tabs.

  12. Successful Completion of the Top-off Upgrade of the Advanced Light Source

    SciTech Connect

    Steier, C.; Bailey, B.; Baptiste, K.; Barry, W.; Biocca, A.; Byrne, W.; Casey, P.; Chin, M.; Donahue, R.; Duarte, R.; Fahmie, M.; Gath, B.; Jacobson, S.; Julian, J.; Jung, J. Y.; Kritscher, M.; Kwiatkowski, S.; Marks, S.; McKean, P.; Mueller, R.

    2010-06-23

    An upgrade of the Advanced Light Source (ALS) to enable top-off operation has been completed during the last four years. The final work centered around radiation safety aspects, culminating in a systematic proof that top-off operation is equally safe as decaying beam operation. Commissioning and transition to full user operations happened in late 2008 and early 2009. Top-off operation at the ALS provides a very large increase in time-averaged brightness (by about a factor of 10) as well as improvements in beam stability. The following sections provide an overview of the radiation safety rationale, commissioning results, as well as experience in user operations.

  13. High Energy Laboratory Astrophysics Experiments using electron beam ion traps and advanced light sources

    NASA Astrophysics Data System (ADS)

    Brown, Gregory V.; Beiersdorfer, Peter; Bernitt, Sven; Eberle, Sita; Hell, Natalie; Kilbourne, Caroline; Kelley, Rich; Leutenegger, Maurice; Porter, F. Scott; Rudolph, Jan; Steinbrugge, Rene; Traebert, Elmar; Crespo-Lopez-Urritia, Jose R.

    2015-08-01

    We have used the Lawrence Livermore National Laboratory's EBIT-I electron beam ion trap coupled with a NASA/GSFC microcalorimeter spectrometer instrument to systematically address problems found in the analysis of high resolution X-ray spectra from celestial sources, and to benchmark atomic physics codes employed by high resolution spectral modeling packages. Our results include laboratory measurements of transition energies, absolute and relative electron impact excitation cross sections, charge exchange cross sections, and dielectronic recombination resonance strengths. More recently, we have coupled to the Max-Plank Institute for Nuclear Physics-Heidelberg's FLASH-EBIT electron beam ion trap to third and fourth generation advanced light sources to measure photoexcitation and photoionization cross sections, as well as, natural line widths of X-ray transitions in highly charged iron ions. Selected results will be presented.

  14. A Superbend X-Ray Microdiffraction Beamline at the Advanced Light Source

    SciTech Connect

    Tamura, N.; Kunz, M.; Chen, K.; Celestre, R.S.; MacDowell, A.A.; Warwick, T.

    2009-03-10

    Beamline 12.3.2 at the Advanced Light Source is a newly commissioned beamline dedicated to x-ray microdiffraction. It operates in both monochromatic and polychromatic radiation mode. The facility uses a superconducting bending magnet source to deliver an X-ray spectrum ranging from 5 to 22 keV. The beam is focused down to {approx} 1 um size at the sample position using a pair of elliptically bent Kirkpatrick-Baez mirrors enclosed in a vacuum box. The sample placed on high precision stages can be raster-scanned under the microbeam while a diffraction pattern is taken at each step. The arrays of diffraction patterns are then analyzed to derive distribution maps of phases, strain/stress and/or plastic deformation inside the sample.

  15. Soft x-ray spectromicroscopy development for materials science at the Advanced Light Source

    SciTech Connect

    Warwick, T.; Padmore, H.; Ade, H.; Hitchcock, A.P.; Rightor, E.G.; Tonner, B.P.

    1996-08-01

    Several third generation synchrotron radiation facilities are now operational and the high brightness of these photon sources offers new opportunities for x-ray microscopy. Well developed synchrotron radiation spectroscopy techniques are being applied in new instruments capable of imaging the surface of a material with a spatial resolution smaller than one micron. There are two aspects to this. One is to further the field of surface science by exploring the effects of spatial variations across a surface on a scale not previously accessible to x-ray measurements. The other is to open up new analytical techniques in materials science using x-rays, on a spatial scale comparable to that of the processes or devices to be studied. The development of the spectromicroscopy program at the Advanced Light Source will employ a variety of instruments, some are already operational. Their development and use will be discussed, and recent results will be presented to illustrate their capabilities.

  16. Intra-beam Scattering and Minimum Achievable Emittance in the Advanced Light Source

    SciTech Connect

    Bane, Karl LF

    2002-08-13

    Intra-beam scattering (IBS) potentially limits the minimum emittance of low-energy storage rings, and this effect strongly influences the choice of energy of damping rings for linear colliders. The Advanced Light Source (ALS) is the third-generation synchrotron light source operating in high-intensity, low-emittance beams at energies up to 2 GeV. It can operate with an emittance coupling of below 1%. We present measurements of the beam growth in three dimensions as a function of current, for normalized natural horizontal emittances approximately 1-10 mm-mrad at energies of 0.7-1.5 GeV, values comparable to the parameters in an NLC damping ring [1]. Using a dedicated diagnostic beamline with an x-ray scintillator imaging system, measurements of the transverse beamsize are made, simultaneously with bunch length measurements using an optical streak camera. The bunch volume growth as a function of bunch current is compared with theoretical estimates, for a parameter space of IBS, where very little experimental data exists so far.

  17. Measurements of Intra-Beam Scattering at Low Emittance in the Advanced Light Source

    SciTech Connect

    Byrd, J.; Corlett, J.; Nishimura, H.; Robin, D.; De Santis, S.; Steier, C.; Wolski, A.; Wu, Y.; Bane, K.; Raubenheimer, T.; Ross, M.; Sheppard, J.; Smith, T.; /SLAC

    2006-03-13

    The beam emittance at the interaction point of linear colliders is expected to be strongly influenced by the emittance of the beams extracted from the damping rings. Intra-beam scattering (IBS) potentially limits the minimum emittance of low-energy storage rings, and this effect strongly influences the choice of energy of damping rings [1]. Theoretical analysis suggests that the NLC damping rings will experience modest emittance growth at 1.98 GeV, however there is little experimental data of IBS effects for very low-emittance machines in the energy regime of interest. The Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory is a third-generation synchrotron light source operating with high-intensity, low-emittance beams at energies of approximately 1-2 GeV, and with emittance coupling capability of 1% or less. We present measurements of the beam growth in three dimensions as a function of current, for normalized natural horizontal emittance of approximately 1-10 mm-mrad at energies of 0.7-1.5 GeV, values comparable to the parameters in an NLC damping ring. Using a dedicated diagnostic beamline with an x-ray scintillator imaging system, measurements of the transverse beamsize are made, and bunch length measurements are made using an optical streak camera. Emittance growth as a function of bunch current is determined, and compared with preliminary calculation estimates.

  18. Backscatter tolerant squeezed light source for advanced gravitational-wave detectors.

    PubMed

    Chua, Sheon S Y; Stefszky, Michael S; Mow-Lowry, Conor M; Buchler, Ben C; Dwyer, Sheila; Shaddock, Daniel A; Lam, Ping Koy; McClelland, David E

    2011-12-01

    We report on the performance of a dual-wavelength resonant, traveling-wave optical parametric oscillator to generate squeezed light for application in advanced gravitational-wave interferometers. Shot noise suppression of 8.6±0.8 dB was measured across the detection band of interest to Advanced LIGO, and controlled squeezing measured over 5900 s. Our results also demonstrate that the traveling-wave design has excellent intracavity backscattered light suppression of 47 dB and incident backscattered light suppression of 41 dB, which is a crucial design issue for application in advanced interferometers.

  19. Photometric Calibration of an EUV Flat Field Spectrometer at the Advanced Light Source

    SciTech Connect

    May, M; Lepson, J; Beiersdorfer, P; Thorn, D; Chen, H; Hey, D; Smith, A

    2002-07-03

    The photometric calibration of ail extreme ultraviolet flat field spectrometer has been done at the Advanced Light Source at LBNL. This spectrometer is used to record spectrum for atomic physics research from highly charged ions in plasmas created in the Livermore electron beam ion traps EBIT-I and SUPEREBIT. Two calibrations were done each with a different gold-coated grating, a 1200 {ell}/mm and a 2400 {ell}/mm, that covered 75-300{angstrom} and 15-160{angstrom}, respectively. The detector for this calibration was a back thinned CCD. The relative calibration was determined for several different incident angles for both gratings. Within the scatter of the data, the calibration was roughly insensitive to the incidence angle for the range of angles investigated.

  20. Estimation of 1D proximity budget impacts due to light source for advanced node design

    NASA Astrophysics Data System (ADS)

    Peng, R. C.; Wu, Tony; Liu, H. H.

    2014-03-01

    The laser impacts on the proximity error are well known in many previous studies and papers. The proximity budget control is more and more important for advanced node design. The goal of this paper is to describe the laser spectral bandwidth and wavelength stability contributions to the proximity budget by considering general line/space and trench pattern design. We performed experiments and modeled the photolithography response using Panoramic Technology HyperLith simulation over a range of laser bandwidth and wavelength stability conditions to quantify the long term and short term stability contributions on wafer-to-wafer and field-to-field proximity variation. Finally, we determine the requirements for current system performance to meet patterning requirements and minimize the laser contribution on proximity error and within 4% of target CD Critical Dimension Uniformity (CDU) budget process requirement [2]. This paper also discusses how the wafer lithography drivers are enabled by ArFi light source technologies.

  1. The Advanced Light Source U8 beam line, 20--300 eV

    SciTech Connect

    Heimann, P.; Warwick, T.; Howells, M.; McKinney, W.; Digennaro, D.; Gee, B.; Yee, D.; Kincaid, B.

    1991-10-01

    The U8 is a beam line under construction at the Advanced Light Source (ALS). The beam line will be described along with calculations of its performance and its current status. An 8 cm period undulator is followed by two spherical collecting mirrors, an entrance slit, spherical gratings having a 15{degree} deviation angle, a moveable exit slit, and refocusing and branching mirrors. Internal water cooling is provided to the metal M1 and M2 mirrors as well as to the gratings. Calculations have been made of both the flux output and the resolution over its photon energy range of 20--300 eV. The design goal was to achieve high intensity, 10{sup 12} photons/sec, at a high resolving power of 10,000. The U8 Participating Research Team (PRT) is planning experiments involving the photoelectron spectroscopy of gaseous atoms and molecules, the spectroscopy of ions and actinide spectroscopy.

  2. The advanced light source — a new tool for research in atomic physics

    NASA Astrophysics Data System (ADS)

    Schlachter, A. S.

    1991-03-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory in Berkeley, California, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Undulators will generate high-brightness, partially coherent, plane polarized, soft x-ray and ultraviolet (XUV) radiation from below 10 eV to above 2 keV. Wigglers and bend magnets will generate high fluxes of x-rays to photon energies above 10 keV. The ALS will have an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms.

  3. The advanced light source: A new tool for research in atomic physics

    NASA Astrophysics Data System (ADS)

    Schlachter, A. S.

    1990-09-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory in Berkeley, California, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Undulators will generate high-brightness, partially coherent, plane polarized, soft-x-ray and ultraviolet (XUV) radiation from below 10 eV to above 2 keV. Wigglers and bend magnets will generate high fluxes of x-rays to photon energies above 10 keV. The ALS will have an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms.

  4. Calibration of a microchannel plate based extreme ultraviolet grazing incident spectrometer at the Advanced Light Source.

    PubMed

    Bakeman, M S; van Tilborg, J; Sokollik, T; Baum, D; Ybarrolaza, N; Duarte, R; Toth, C; Leemans, W P

    2010-10-01

    We present the design and calibration of a microchannel plate based extreme ultraviolet spectrometer. Calibration was performed at the Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL). This spectrometer will be used to record the single shot spectrum of radiation emitted by the tapered hybrid undulator (THUNDER) undulator installed at the LOASIS GeV-class laser-plasma-accelerator. The spectrometer uses an aberration-corrected concave grating with 1200 lines/mm covering 11-62 nm and a microchannel plate detector with a CsI coated photocathode for increased quantum efficiency in the extreme ultraviolet. A touch screen interface controls the grating angle, aperture size, and placement of the detector in vacuum, allowing for high-resolution measurements over the entire spectral range.

  5. An aberration corrected photoemission electron microscope at the advanced light source

    SciTech Connect

    Feng, J.; MacDowell, A.A.; Duarte, R.; Doran, A.; Forest, E.; Kelez, N.; Marcus, M.; Munson, D.; Padmore, H.; Petermann, K.; Raoux, S.; Robin, D.; Scholl, A.; Schlueter, R.; Schmid, P.; Stohr, J.; Wan, W.; Wei, D.H.; Wu, Y.

    2003-11-01

    Design of a new aberration corrected Photoemission electron microscope PEEM3 at the Advanced Light Source is outlined. PEEM3 will be installed on an elliptically polarized undulator beamline and will be used for the study of complex materials at high spatial and spectral resolution. The critical components of PEEM3 are the electron mirror aberration corrector and aberration-free magnetic beam separator. The models to calculate the optical properties of the electron mirror are discussed. The goal of the PEEM3 project is to achieve the highest possible transmission of the system at resolutions comparable to our present PEEM2 system (50 nm) and to enable significantly higher resolution, albeit at the sacrifice of intensity. We have left open the possibility to add an energy filter at a later date, if it becomes necessary driven by scientific need to improve the resolution further.

  6. Calibration of a microchannel plate based extreme ultraviolet grazing incident spectrometer at the Advanced Light Source

    SciTech Connect

    Bakeman, M. S.; Tilborg, J. van; Sokollik, T.; Baum, D.; Ybarrolaza, N.; Duarte, R.; Toth, C.; Leemans, W. P.

    2010-10-15

    We present the design and calibration of a microchannel plate based extreme ultraviolet spectrometer. Calibration was performed at the Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL). This spectrometer will be used to record the single shot spectrum of radiation emitted by the tapered hybrid undulator (THUNDER) undulator installed at the LOASIS GeV-class laser-plasma-accelerator. The spectrometer uses an aberration-corrected concave grating with 1200 lines/mm covering 11-62 nm and a microchannel plate detector with a CsI coated photocathode for increased quantum efficiency in the extreme ultraviolet. A touch screen interface controls the grating angle, aperture size, and placement of the detector in vacuum, allowing for high-resolution measurements over the entire spectral range.

  7. A new synchrotron light source at Louisiana State University's Center for Advanced Microstructures and Devices

    NASA Astrophysics Data System (ADS)

    Stockbauer, Roger L.; Ajmera, Pratul; Poliakoff, Erwin D.; Craft, Ben C.; Saile, Volker

    1990-05-01

    A 1.2-GeV synchrotron light source is being constructed at the Center for Advanced Microstructures and Devices (CAMD) at Louisiana State University. The expressed purpose of the center, which has been funded by a grant from the US Department of Energy, is to develop X-ray lithography techniques for manufacturing microcircuits, although basic science programs are also being established. The storage ring will be optimized for the soft-X-ray region and will be the first commercially manufactured electron storage ring in the United States. The magnetic lattice is based on a design developed by Chasman and Green and will allow up to three insertion devices to be installed for higher-energy and higher-intensity radiation. In addition to the lithography effort, experimental programs are being established in physics, chemistry, and related areas.

  8. Magnetic design of trim excitations for the advanced light source storage ring sextupole

    SciTech Connect

    Marks, S.

    1995-06-01

    The Advanced Light Source (ALS) storage ring sextupole is a unique multi-purpose magnet. It is designed to operate as a sextupole with three auxiliary trim modes: horizontal steering, vertical steering, and skew quadrupole. A perturbation theory for iron-dominated magnets developed by Klaus Halbach provides the basis for this design. The three trim excitations are produced by violating sextupole symmetry and are thus perturbations of the normal sextupole excitation. The magnet was designed such that all four modes are decoupled and can be excited independently. This paper discusses the use of Halbach`s perturbation theory to design the trim functions and to evaluate the primary asymmetry in the sextupole mode, namely, a gap in the return yoke to accommodate the vacuum chamber.

  9. Magnetic design of trim excitations for the Advanced Light Source storage ring sextupole

    SciTech Connect

    Marks, S.

    1996-07-01

    The Advanced Light Source (ALS) storage ring sextupole is a unique multi-purpose magnet. It is designed to operate as a sextupole with three auxiliary trim modes: horizontal steering, vertical steering, and skew quadrupole. A perturbation theory for iron-dominated magnets developed by Klaus Halbach provides the basis for this design. The three trim excitations are produced by violating sextupole symmetry and are thus perturbations of the normal sextupole excitation. The magnet was designed such that all four modes are decoupled and can be excited independently. This paper discusses the use of Halbach`s perturbation theory to design the trim functions and to evaluate the primary asymmetry in the sextupole mode, namely, a gap in the return yoke to accommodate the vacuum chamber.

  10. Synchrotron X-Ray Microdiffraction Studies of Electromigration in Interconnect lines at the Advanced Light Source

    SciTech Connect

    Tamura, Nobumichi; Chen, Kai; Kunz, Martin

    2009-12-01

    Synchrotron polychromatic X-ray microdiffraction is a particularly suitable technique to study in situ the effect of electromigration in metal interconnects as add spatial resolution to grain orientation and strain sensitivity. This technique has been extensively used at the Advanced Light Source to monitor changes in aluminum and copper interconnect test structures while high-density current is passed into them during accelerated tests at elevated temperature. One of the principal findings is the observation of electromigration-induced plasticity in the metal lines that appear during the very early stages of electromigration. In some of the lines, high density of geometrically necessary dislocation are formed leading to additional diffusion paths causing an enhancement of electromigration effect at test temperature.

  11. Magnetic properties of the ALS (Advanced Light Source) booster synchrotron engineering model magnets

    SciTech Connect

    Keller, R.; Green, M.I.; Hoyer, E.; Koo, Y.M.; Luchini, K.; Marks, S.; Milburn, J.; Nelson, D.H.

    1989-03-01

    The Advanced Light Source (ALS) at Lawrence Berkeley Laboratory is designed to be a third-generation electron storage ring producing high-brightness VUV and X-ray radiation from wiggler and undulator insertion devices. Engineering models of all lattice magnets that are to be installed in the storage ring and its booster synchrotron have been built and are being tested to verify their performance. This paper is concerned with the magnets that form the booster lattice: dipoles, quadrupoles, sextupoles, and corrector dipoles (steerers). After a brief outline of measurement techniques and equipment, the major design parameters of these magnets are listed. Measured effective lengths and multipole field errors are then given for each type. All engineering models meet the specifications, and tracking studies including the measured systematic field errors show acceptable performance of the booster synchrotron; hence the designs are qualified for production. 3 refs., 7 figs., 4 tabs.

  12. Toward femtosecond X-ray spectroscopy at the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Chong, Henry Herng Wei

    The realization of tunable, ultrashort pulse x-ray sources promises to open new venues of science and to shed new light on long-standing problems in condensed matter physics and chemistry. Fundamentally new information can now be accessed. Used in a pump-probe spectroscopy, ultrashort x-ray pulses provide a means to monitor atomic rearrangement and changes in electronic structure in condensed-matter and chemical systems on the physically-limiting time-scales of atomic motion. This opens the way for the study of fast structural dynamics and the role they play in phase transitions, chemical reactions and the emergence of exotic properties in materials with strongly interacting degrees of freedom. The ultrashort pulse x-ray source developed at the Advanced Light Source at the Lawrence Berkeley Laboratory is based on electron slicing in storage rings, and generates ˜100 femtosecond pulses of synchrotron radiation spanning wavelengths from the far-infrared to the hard x-ray region of the electromagnetic spectrum. The tunability of the source allows for the adaptation of a broad range of static x-ray spectroscopies to useful pump-probe measurements. Initial experiments are attempted on transition metal complexes that exhibit relatively large structural changes upon photo-excitation and which have excited-state evolution determined by strongly interacting structural, electronic and magnetic degrees of freedom. Specifically, iron(II) complexes undergo a spin-crossover transition upon optical irradiation. The dynamics of the transition involve a metal-to-ligand charge transfer, a DeltaS = 2 change in magnetic moment and 10% bond dilation in the first coordination shell of the iron. Studies of the electronic dynamics are studied with time-resolved optical absorption measurements. The current progress of time-resolved structural studies to complete the picture of the spin-crossover transition is presented.

  13. Toward Femtosecond X-ray Spectroscopy at the Advanced Light Source

    SciTech Connect

    Chong, Henry Herng Wei

    2004-01-01

    The realization of tunable, ultrashort pulse x-ray sources promises to open new venues of science and to shed new light on long-standing problems in condensed matter physics and chemistry. Fundamentally new information can now be accessed. Used in a pump-probe spectroscopy, ultrashort x-ray pulses provide a means to monitor atomic rearrangement and changes in electronic structure in condensed-matter and chemical systems on the physically-limiting time-scales of atomic motion. This opens the way for the study of fast structural dynamics and the role they play in phase transitions, chemical reactions and the emergence of exotic properties in materials with strongly interacting degrees of freedom. The ultrashort pulse x-ray source developed at the Advanced Light Source at the Lawrence Berkeley Laboratory is based on electron slicing in storage rings, and generates ~100 femtosecond pulses of synchrotron radiation spanning wavelengths from the far-infrared to the hard x-ray region of the electromagnetic spectrum. The tunability of the source allows for the adaptation of a broad range of static x-ray spectroscopies to useful pump-probe measurements. Initial experiments are attempted on transition metal complexes that exhibit relatively large structural changes upon photo-excitation and which have excited-state evolution determined by strongly interacting structural, electronic and magnetic degrees of freedom. Specifically, iron(II) complexes undergo a spin-crossover transition upon optical irradiation. The dynamics of the transition involve a metal-to-ligand charge transfer, a ΔS=2 change in magnetic moment and 10% bond dilation in the first coordination shell of the iron. Studies of the electronic dynamics are studied with time-resolved optical absorption measurements. The current progress of time-resolved structural studies to complete the picture of the spin-crossover transition is presented.

  14. An ALS handbook: A summary of the capabilities and characteristics of the advanced light source

    SciTech Connect

    Not Available

    1989-04-01

    This booklet aims to provide the prospective user of the Advanced Light Source with a concise description of the radiation a researcher might expect at his or her experimental station. The focus is therefore on the characteristics of the light that emerges from insertion devices and bending magnets and on how components of the beam lines further alter the properties of the radiation. The few specifications and operating parameters of the ALS storage ring that are of interest are those that directly determine the radiation characteristics. Sections 4 through 5 are primarily devoted to summary presentations, by means of performance plots and tabular compilations, of radiation characteristics at the ALS--spectral brightness, flux, coherent power, resolution, etc.--assuming a representative set of three undulators and one wiggler and a corresponding set of four beam lines. As a complement to these performance summaries, Section 1 is a general introductory discussion of synchrotron radiation and the ALS, and Section 2 discusses the properties of the stored electron beam that affect the radiation. Section 3 then provides an introduction to the characteristics of synchrotron radiation from bending magnets, wigglers, and undulators. In addition, Section 5 briefly introduces the theory of diffraction-grating and crystal monochromators. As compared with previous editions of this booklet, the performance plots and tabular compilations of the ALS radiation characteristics are now based on conservative engineering designs rather than preliminary physics designs.

  15. Advanced light source vacuum policy and vacuum guidelines for beamlines and experiment endstations

    SciTech Connect

    Hussain, Z.

    1995-08-01

    The purpose of this document is to: (1) Explain the ALS vacuum policy and specifications for beamlines and experiment endstations. (2) Provide guidelines related to ALS vacuum policy to assist in designing beamlines which are in accordance with ALS vacuum policy. This document supersedes LSBL-116. The Advanced Light Source is a third generation synchrotron radiation source whose beam lifetime depends on the quality of the vacuum in the storage ring and the connecting beamlines. The storage ring and most of the beamlines share a common vacuum and are operated under ultra-high-vacuum (UHV) conditions. All endstations and beamline equipment must be operated so as to avoid contamination of beamline components, and must include proper safeguards to protect the storage ring vacuum from an accidental break in the beamline or endstation vacuum systems. The primary gas load during operation is due to thermal desorption and electron/photon induced desorption of contaminants from the interior of the vacuum vessel and its components. The desorption rates are considerably higher for hydrocarbon contamination, thus considerable emphasis is placed on eliminating these sources of contaminants. All vacuum components in a beamline and endstation must meet the ALS vacuum specifications. The vacuum design of both beamlines and endstations must be approved by the ALS Beamline Review Committee (BRC) before vacuum connections to the storage ring are made. The vacuum design is first checked during the Beamline Design Review (BDR) held before construction of the beamline equipment begins. Any deviation from the ALS vacuum specifications must be approved by the BRC prior to installation of the equipment on the ALS floor. Any modification that is incorporated into a vacuum assembly without the written approval of the BRC is done at the user`s risk and may lead to rejection of the whole assembly.

  16. Preparation and characterization of B4C coatings for advanced research light sources

    PubMed Central

    Störmer, Michael; Siewert, Frank; Sinn, Harald

    2016-01-01

    X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B4C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30–60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B4C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B4C layers are discussed according to thickness uniformity, density, microroughness and thermal stability. The variation of layer thickness in the tangential and sagittal directions was investigated in order to estimate the achieved level of uniformity over the whole deposition area, which is

  17. Preparation and characterization of B4C coatings for advanced research light sources.

    PubMed

    Störmer, Michael; Siewert, Frank; Sinn, Harald

    2016-01-01

    X-ray optical elements are required for beam transport at the current and upcoming free-electron lasers and synchrotron sources. An X-ray mirror is a combination of a substrate and a coating. The demand for large mirrors with single layers consisting of light or heavy elements has increased during the last few decades; surface finishing technology is currently able to process mirror lengths up to 1 m with microroughness at the sub-nanometre level. Additionally, thin-film fabrication is able to deposit a suitable single-layer material, such as boron carbide (B4C), some tens of nanometres thick. After deposition, the mirror should provide excellent X-ray optical properties with respect to coating thickness errors, microroughness values and slope errors; thereby enabling the mirror to transport the X-ray beam with high reflectivity, high beam flux and an undistorted wavefront to an experimental station. At the European XFEL, the technical specifications of the future mirrors are extraordinarily challenging. The acceptable shape error of the mirrors is below 2 nm along the whole length of 1 m. At the Helmholtz-Zentrum Geesthacht (HZG), amorphous layers of boron carbide with thicknesses in the range 30-60 nm were fabricated using the HZG sputtering facility, which is able to cover areas up to 1500 mm long by 120 mm wide in one step using rectangular B4C sputtering targets. The available deposition area is suitable for the specified X-ray mirror dimensions of upcoming advanced research light sources such as the European XFEL. The coatings produced were investigated by means of X-ray reflectometry and interference microscopy. The experimental results for the B4C layers are discussed according to thickness uniformity, density, microroughness and thermal stability. The variation of layer thickness in the tangential and sagittal directions was investigated in order to estimate the achieved level of uniformity over the whole deposition area, which is considerably

  18. The U5.0 undulator design for the advanced light source at LBL

    NASA Astrophysics Data System (ADS)

    Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.; Humphries, D.; Kincaid, B.; Lancaster, H.; Plate, D.; Savoy, R.

    1990-05-01

    The U5.0 undulator, currently under design, is the first in a series of insertion devices planned for the Advanced Light Source at LBL. U5.0 parameters include a 5-cm period and a 5-m length with an 0.837-T maximum field at a 14-mm gap. A hybrid configuration utilizing NdFeB permanent magnet material and vanadium permendur poles is used for the magnetic structure. Construction is modular with many pole assemblies attached to a pole mount, which in turn is fastened onto one of the backing beams. Vertical field integral correction at the ends is accomplished with permanent magnet rotators. The support structure features a four-post configuration, a rigid base with three kinematic floor supports, and two rigid 5-m long backing beams that fit within the 2.4-m-high accelerator enclosure. The drive system is computer-controlled using a stepper motor and shaft encoder coupled to a roller-screw/nut and chain drive train. Vacuum chamber design is a rigid configuration with a 10 mm vertical by 218 mm horizontal aperture of 5.5 m length. Chamber fabrication features a two-piece welded chamber of 5083 H321 aluminum. Pumping is with ion and titanium sublimation pumps.

  19. The advanced light source at Lawrence Berkeley laboratory: a new tool for research in atomic physics

    NASA Astrophysics Data System (ADS)

    Schlachter, Alfred S.; Robinson, Arthur L.

    1991-04-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Based on a low-emittance electron storage ring optimized to operate at 1.5 GeV, the ALS will have 10 long straight sections available for insertion devices (undulators and wigglers) and 24 high-quality bend-magnet ports. The short pulse width (30-50 ps) will be ideal for time-resolved measurements. Undulators will generate high-brightness partially coherent soft X-ray and ultraviolet (XUV) radiation from below 10 eV to above 2 keV; this radiation is plane polarized. Wigglers and bend magnets will extend the spectrum by generating high fluxes of X-rays to photon energies above 10 keV. The ALS will have an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms. The high brightness will open new areas of research in the materials sciences, such as spatially resolved spectroscopy (spectromicroscopy), and in biology, such as X-ray microscopy with element-specific sensitivity; the high flux will allow measurements in atomic physics and chemistry to be made with tenuous gas-phase targets. Technological applications could include lithography and nano-fabrication.

  20. Synchrotron X-Ray Microdiffraction Studies of Electromigration in Interconnect lines at the Advanced Light Source

    SciTech Connect

    Tamura, Nobumichi; Chen, Kai; Kunz, Martin

    2009-05-01

    Synchrotron polychromatic X-ray microdiffraction is a particularly suitable technique to study in situ the effect of electromigration in metal interconnects as add spatial resolution to grain orientation and strain sensitivity. This technique has been extensively used at the Advanced Light Source to monitor changes in aluminum and copper interconnect test structures while high-density current is passed into them during accelerated tests at elevated temperature. One of the principal findings is the observation of electromigration-induced plasticity in the metal lines that appear during the very early stages of electromigration. In some of the lines, high density of geometrically necessary dislocation are formed leading to additional diffusion paths causing an enhancement of electromigration effect at test temperature. This paper presents an overview of the principal results obtained from X-ray microdiffraction studies of electromigration effects on aluminum and copper interconnects at the ALS throughout continuous efforts that spanned over a decade (1998-2008) from approximately 40 weeks of combined beamtime.

  1. Applications of the Advanced Light Source to problems in the earth, soil, and environmental sciences report of the workshop

    SciTech Connect

    Not Available

    1992-10-01

    This report discusses the following topics: ALS status and research opportunities; advanced light source applications to geological materials; applications in the soil and environmental sciences; x-ray microprobe analysis; potential applications of the ALS in soil and environmental sciences; and x-ray spectroscopy using soft x-rays: applications to earth materials.

  2. The U5.0 Undulator for the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W. V.; Humphries, D.; Kincaid, B.; Lancaster, H.; Plate, D.

    1992-01-01

    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.

  3. XUV synchrotron optical components for the Advanced Light Source: Summary of the requirements and the developmental program

    SciTech Connect

    McKinney, W.; Irick, S.; Lunt, D.

    1992-07-01

    We give a brief summary of the requirements for water cooled optical components for the Advanced Light Source (ALS), a third generation synchrotron radiation source under construction at Lawrence Berkeley Laboratory (LBL). Materials choices, surface figure and smoothness specifications, and metrology systems for measuring the plated metal surfaces are discussed. Results from a finished water cooled copper alloy mirror will be used to demonstrate the state of the art in optical metrology with the Takacs Long Trace Profiler (LTP II).

  4. A beamline for high-pressure studies at the Advanced Light Source with a superconducting bending magnet as the source.

    PubMed

    Kunz, Martin; MacDowell, Alastair A; Caldwell, Wendel A; Cambie, Daniella; Celestre, Richard S; Domning, Edward E; Duarte, Robert M; Gleason, Arianna E; Glossinger, James M; Kelez, Nicholas; Plate, David W; Yu, Tony; Zaug, Joeseph M; Padmore, Howard A; Jeanloz, Raymond; Alivisatos, A Paul; Clark, Simon M

    2005-09-01

    A new facility for high-pressure diffraction and spectroscopy using diamond anvil high-pressure cells has been built at the Advanced Light Source on beamline 12.2.2. This beamline benefits from the hard X-radiation generated by a 6 T superconducting bending magnet (superbend). Useful X-ray flux is available between 5 keV and 35 keV. The radiation is transferred from the superbend to the experimental enclosure by the brightness-preserving optics of the beamline. These optics are comprised of a plane parabola collimating mirror, followed by a Kohzu monochromator vessel with Si(111) crystals (E/DeltaE approximately equal 7000) and W/B4C multilayers (E/DeltaE approximately equal 100), and then a toroidal focusing mirror with variable focusing distance. The experimental enclosure contains an automated beam-positioning system, a set of slits, ion chambers, the sample positioning goniometry and area detector (CCD or image-plate detector). Future developments aim at the installation of a second endstation dedicated to in situ laser heating and a dedicated high-pressure single-crystal station, applying both monochromatic and polychromatic techniques.

  5. A BEAMLINE FOR HIGH PRESSURE STUDIES AT THE ADVANCED LIGHT SOURCE WITH A SUPERCONDUCTING BENDING MAGNET AS THE SOURCE

    SciTech Connect

    Kunz, M; MacDowell, A A; Caldwell, W A; Cambie, D; Celestre, R S; Domning, E E; Duarte, R M; Gleason, A; Glossinger, J; Kelez, N; Plate, D W; Yu, T; Zaug, J M; Padmore, H A; Jeanloz, R; Alivisatos, A P; Clark, S M

    2005-04-19

    A new facility for high-pressure diffraction and spectroscopy using diamond anvil high-pressure cells has been built at the Advanced Light Source on Beamline 12.2.2. This beamline benefits from the hard X-radiation generated by a 6 Tesla superconducting bending magnet (superbend). Useful x-ray flux is available between 5 keV and 35 keV. The radiation is transferred from the superbend to the experimental enclosure by the brightness preserving optics of the beamline. These optics are comprised of: a plane parabola collimating mirror (M1), followed by a Kohzu monochromator vessel with a Si(111) crystals (E/{Delta}E {approx} 7000) and a W/B{sub 4}C multilayer (E/{Delta}E {approx} 100), and then a toroidal focusing mirror (M2) with variable focusing distance. The experimental enclosure contains an automated beam positioning system, a set of slits, ion chambers, the sample positioning goniometry and area detectors (CCD or image-plate detector). Future developments aim at the installation of a second end station dedicated for in situ laser-heating on one hand and a dedicated high-pressure single-crystal station, applying both monochromatic as well as polychromatic techniques.

  6. Light Sources 2007

    NASA Astrophysics Data System (ADS)

    Liu, M. Q.; Devonshire, R.

    2007-04-01

    This volume contains the proceedings of the 11th International Symposium on the Science and Technology of Light Sources (LS:11) held in Fudan University, Shanghai, China in the period May 20th to 24th, 2007. In the 32 years since the first symposium was held in Loughborough, UK, the LS series has established itself as the major international event which brings together on a regular basis the world's leading scientists and engineers involved in the research and development of light source technologies. The participants come from the R&D laboratories of the world’s leading light source manufacturing companies and from research groups in universities, government laboratories and research institutes. The highly multi-disciplinary nature of the field results in a unique mix of physicists, chemists, chemical physicists, materials scientists and electrical, electronic and mechanical engineers attending the symposia. The more than 250 papers in these LS:11 proceedings provide an excellent overview of the current status of light source science and technology. The energy efficiency and light emission characteristics of existing technologies continue to be improved, solid state technologies are advancing rapidly and innovation flourishes generally. Audience Professional scientists and engineers involved in light source related R&D. Postgraduate-level students in the physical sciences, applied mathematics, materials science, and electrical and electronic engineering. The contents will also be of interest to anyone with a background in science and engineering wishing to gain an overview of current activity in this important global industry and research field.

  7. Soft x-ray optics for spectromicroscopy at the Advanced Light Source

    SciTech Connect

    Padmore, H.A.

    1996-09-01

    A variety of systems for performing spectromicroscopy, spatially resolved spectroscopy, are in operation or under construction at the Advanced Light Source (ALS). For example, part of the program is centered around the surface analysis problems of local semiconductor industries, and this has required the construction of a microscope with wafer handling, fiducialization, optical microscopy, coordinated ion beam etching, and X-ray Photoelectron Spectroscopy (XPS) integrated in this case with Kirkpatrick-Baez (K-B) grazing incidence micro-focusing optics. The microscope is to be used in conjunction with a highly efficient entrance slitless Spherical Grating Monochromator (SGM). The design and expected performance of this instrument will be described, with emphasis on the production of the elliptically curved surfaces of the K-B mirrors by elastic bending of flat mirror substrates. For higher resolution, zone-plate (Z-P) focusing optics are used and one instrument, a Scanning Transmission X-ray Microscope (STXM) is in routine operation on undulator beamline 7.0. A second Z-P based system is being commissioned on the same beamline, and differs from the STXM in that it will operate at Ultra-High Vacuum (UHV) and will be able to perform XPS at 0.1 {micro}m spatial resolution. Spatially resolved X-ray Absorption Spectroscopy (XAS) can be performed by imaging electrons photoemitted from a material with a Photo-Emission Electron Microscope (PEEM). The optical requirements of a beamline designed for PEEM are very different to those of micro-focus systems and they give examples of bending magnet and undulator based instruments.

  8. Light Sources and Lighting Circuits

    NASA Astrophysics Data System (ADS)

    Honda, Hisashi; Suwa, Takumi; Yasuda, Takeo; Ohtani, Yoshihiko; Maehara, Akiyoshi; Okada, Atsunori; Komatsu, Naoki; Mannami, Tomoaki

    According to the Machinery Statistics of the Ministry of Economy, Trade and Industry, the production of incandescent lamps in Japan in 2007 was 990 million units (90.0% of the previous year's total), in which the production of incandescent lamps for general lighting was 110 million units (90.0% of the previous year's total) and of tungsten-halogen lamps was 44 million units (96.6% of the previous year's total). The production of fluorescent lamps was 927 million units (93.9% of the previous year's total), in which general fluorescent lamps, excluding those for LCD back lighting, was 320 million units (87.2% of the previous year's total). Also, the production of HID lamps was 10 million units (101.5% of the previous year's total). On the other hand, when the numbers of sales are compared with the sales of the previous year, incandescent lamps for general use was 99.8%, tungsten-halogen lamps was 96.9%, fluorescent lamps was 95.9%, and HID lamps was 98.9%. Self-ballasted fluorescent lamps alone showed an increase in sales as strong as 29 million units, or 121.7% of the previous year's sales. It is considered that the switchover of incandescent lamps to HID lamps was promoted for energy conservation and carbon dioxide reduction with the problem of global warming in the background. In regard to exhibitions, Lighting Fair 2007 was held in Tokyo in March, and LIGHTFAIR INTERNATIONAL 2007 was held in New York in May. Regarding academic conferences, LS:11 (the 11th International Symposium on the Science & Technology of Light Sources) was held in Shanghai in May, and the First International Conference on White LEDs and Solid State Lighting was held in Tokyo in November. Both conferences suggested that there are strong needs and concerns now about energy conservation, saving natural resources, and restrictions of hazardous materials. In regard to incandescent lamps, the development of products aiming at higher efficacy, electric power savings, and longer life was advanced by

  9. Influence of Light Conditions and Light Sources on Clinical Measurement of Natural Teeth Color using VITA Easyshade Advance 4,0® Spectrophotometer. Pilot Study.

    PubMed Central

    Posavec, Ivona; Prpić, Vladimir

    2016-01-01

    Objectives The purpose of this study was to evaluate and compare lightness (L), chroma (C) and hue (h), green-red (a) and blue-yellow (b) character of the color of maxillary right central incisors in different light conditions and light sources. Materials and methods Two examiners who were well trained in digital color evaluation participated in the research. Intraclass correlation coefficients (ICCs) were used to analyze intra- and interobserver reliability. The LCh and L*a*b* values were determined at 08.15 and at 10.00 in the morning under three different light conditions. Tooth color was assessed in 10 subjects using intraoral spectrophotometer VITA Easyshade Advance 4.0® set at the central region of the vestibular surface of the measured tooth. Results Intra- and interobserver ICC values were high for both examiners and ranged from 0.57 to 0.99. Statistically significant differences in LCh and L*a*b* values measured in different time of the day and certain light condition were not found (p>0.05). Statistically significant differences in LCh and L*a*b* values measured under three different light conditions were not found, too (p>0.05). Conclusions VITA Easyshade Advance 4.0® is reliable enough for daily clinical work in order to assess tooth color during the fabrication of esthtic appliances because it is not dependent on light conditions and light sources. PMID:28275281

  10. Flame Experiments at the Advanced Light Source: New Insights into Soot Formation Processes

    PubMed Central

    Hansen, Nils; Skeen, Scott A.; Michelsen, Hope A.; Wilson, Kevin R.; Kohse-Höinghaus, Katharina

    2014-01-01

    The following experimental protocols and the accompanying video are concerned with the flame experiments that are performed at the Chemical Dynamics Beamline of the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory1-4. This video demonstrates how the complex chemical structures of laboratory-based model flames are analyzed using flame-sampling mass spectrometry with tunable synchrotron-generated vacuum-ultraviolet (VUV) radiation. This experimental approach combines isomer-resolving capabilities with high sensitivity and a large dynamic range5,6. The first part of the video describes experiments involving burner-stabilized, reduced-pressure (20-80 mbar) laminar premixed flames. A small hydrocarbon fuel was used for the selected flame to demonstrate the general experimental approach. It is shown how species’ profiles are acquired as a function of distance from the burner surface and how the tunability of the VUV photon energy is used advantageously to identify many combustion intermediates based on their ionization energies. For example, this technique has been used to study gas-phase aspects of the soot-formation processes, and the video shows how the resonance-stabilized radicals, such as C3H3, C3H5, and i-C4H5, are identified as important intermediates7. The work has been focused on soot formation processes, and, from the chemical point of view, this process is very intriguing because chemical structures containing millions of carbon atoms are assembled from a fuel molecule possessing only a few carbon atoms in just milliseconds. The second part of the video highlights a new experiment, in which an opposed-flow diffusion flame and synchrotron-based aerosol mass spectrometry are used to study the chemical composition of the combustion-generated soot particles4. The experimental results indicate that the widely accepted H-abstraction-C2H2-addition (HACA) mechanism is not the sole molecular growth process responsible for the formation of the

  11. Flame experiments at the advanced light source: new insights into soot formation processes.

    PubMed

    Hansen, Nils; Skeen, Scott A; Michelsen, Hope A; Wilson, Kevin R; Kohse-Höinghaus, Katharina

    2014-05-26

    The following experimental protocols and the accompanying video are concerned with the flame experiments that are performed at the Chemical Dynamics Beamline of the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory(1-4). This video demonstrates how the complex chemical structures of laboratory-based model flames are analyzed using flame-sampling mass spectrometry with tunable synchrotron-generated vacuum-ultraviolet (VUV) radiation. This experimental approach combines isomer-resolving capabilities with high sensitivity and a large dynamic range(5,6). The first part of the video describes experiments involving burner-stabilized, reduced-pressure (20-80 mbar) laminar premixed flames. A small hydrocarbon fuel was used for the selected flame to demonstrate the general experimental approach. It is shown how species' profiles are acquired as a function of distance from the burner surface and how the tunability of the VUV photon energy is used advantageously to identify many combustion intermediates based on their ionization energies. For example, this technique has been used to study gas-phase aspects of the soot-formation processes, and the video shows how the resonance-stabilized radicals, such as C3H3, C3H5, and i-C4H5, are identified as important intermediates(7). The work has been focused on soot formation processes, and, from the chemical point of view, this process is very intriguing because chemical structures containing millions of carbon atoms are assembled from a fuel molecule possessing only a few carbon atoms in just milliseconds. The second part of the video highlights a new experiment, in which an opposed-flow diffusion flame and synchrotron-based aerosol mass spectrometry are used to study the chemical composition of the combustion-generated soot particles(4). The experimental results indicate that the widely accepted H-abstraction-C2H2-addition (HACA) mechanism is not the sole molecular growth process responsible for the formation

  12. Developments in synchrotron x-ray micro-tomography for in-situ materials analysis at the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Barnard, Harold S.; MacDowell, A. A.; Parkinson, D. Y.; Venkatakrishnan, S. V.; Panerai, F.; Mansour, N. N.

    2016-10-01

    The Advanced Light Source (ALS) is a third-generation synchrotron X-ray source that operates as a user facility with more than 40 beamlines hosting over 2000 users per year. Synchrotron sources like the ALS provide high quality X-ray beams, with flux that is several orders of magnitude higher than lab-based sources. This is particularly advantageous for dynamic applications because it allows for high-speed, high-resolution imaging and microscale tomography. The hard X-ray beamline 8.3.2 at the Advanced Light Source enables imaging of samples at high temperatures and pressures, with mechanical loading and other realistic conditions using environmental test cells. These test cells enable experimental observation of samples undergoing dynamic microstructural changes in-situ. We present recent instrumentation developments that allow for continuous tomography with scan rates approaching 1 Hz per 3D image. In addition, our use of iterative reconstruction techniques allows for improved image quality despite fewer images and low exposure times used during fast tomography compared to traditional Fourier reconstruction methods.

  13. Improving on-wafer CD correlation analysis using advanced diagnostics and across-wafer light-source monitoring

    NASA Astrophysics Data System (ADS)

    Alagna, Paolo; Zurita, Omar; Rechtsteiner, Gregory; Lalovic, Ivan; Bekaert, Joost

    2014-04-01

    With the implementation of multi-patterning ArF-immersion for sub 20nm integrated circuits (IC), advances in equipment monitoring and control are needed to support on-wafer yield performance. These in-situ equipment monitoring improvements, along with advanced litho-cell corrections based on on-wafer measurements, enable meeting stringent overlay and CD control requirements for advanced lithography patterning. The importance of light-source performance on lithography pattering (CD and overlay) has been discussed in previous publications.[1-3] Recent developments of Cymer ArF light-source metrology and on-board monitoring enable end-users to detect, for each exposed wafer, changes in the near-field and far-field spatial profiles and polarization performance, [4-6] in addition to the key `optical' scalar parameters, such as bandwidth, wavelength and energy. The major advantage of this capability is that the key performance metrics are sampled at rates matched to wafer performance, e.g. every exposure field across the wafer, which is critical for direct correlation with on-wafer performance for process control and excursion detection.

  14. Proposal to DOE Basic Energy Sciences: Ultrafast X-ray science facility at the Advanced Light Source

    SciTech Connect

    Schoenlein, Robert W.; Falcone, Roger W.; Abela, R.; Alivisatos, A.P.; Belkacem, A.; Berrah, N.; Bozek, J.; Bressler, C.; Cavalleri, A.; Chergui, M.; Glover, T.E.; Heimann, P.A.; Hepburn, J.; Larsson, J.; Lee, R.W.; McCusker, J.; Padmore, H.A.; Pattison, P.; Pratt, S.T.; Shank, C.V.; Wark, J.; Chang, Z.; Robin, D.W.; Schlueter, R.D.; Zholents, A.A.; Zolotorev, M.S.

    2001-12-12

    We propose to develop a true user facility for ultrafast x-ray science at the Advanced Light Source. This facility will be unique in the world, and will fill a critical need for the growing ultrafast x-ray research community. The development of this facility builds upon the expertise from long-standing research efforts in ultrafast x-ray spectroscopy and the development of femtosecond x-ray sources and techniques at both the Lawrence Berkeley National Laboratory and at U.C. Berkeley. In particular, the technical feasibility of a femtosecond x-ray beamline at the ALS has already been demonstrated, and existing ultrafast laser technology will enable such a beamline to operate near the practical limit for femtosecond x-ray flux and brightness from a 3rd generation synchrotron.

  15. Photonic crystal light source

    DOEpatents

    Fleming, James G.; Lin, Shawn-Yu; Bur, James A.

    2004-07-27

    A light source is provided by a photonic crystal having an enhanced photonic density-of-states over a band of frequencies and wherein at least one of the dielectric materials of the photonic crystal has a complex dielectric constant, thereby producing enhanced light emission at the band of frequencies when the photonic crystal is heated. The dielectric material can be a metal, such as tungsten. The spectral properties of the light source can be easily tuned by modification of the photonic crystal structure and materials. The photonic crystal light source can be heated electrically or other heating means. The light source can further include additional photonic crystals that exhibit enhanced light emission at a different band of frequencies to provide for color mixing. The photonic crystal light source may have applications in optical telecommunications, information displays, energy conversion, sensors, and other optical applications.

  16. Biological soft X-ray tomography on beamline 2.1 at the Advanced Light Source

    PubMed Central

    Le Gros, Mark A.; McDermott, Gerry; Cinquin, Bertrand P.; Smith, Elizabeth A.; Do, Myan; Chao, Weilun L.; Naulleau, Patrick P.; Larabell, Carolyn A.

    2014-01-01

    Beamline 2.1 (XM-2) is a transmission soft X-ray microscope in sector 2 of the Advanced Light Source at Lawrence Berkeley National Laboratory. XM-2 was designed, built and is now operated by the National Center for X-ray Tomography as a National Institutes of Health Biomedical Technology Research Resource. XM-2 is equipped with a cryogenic rotation stage to enable tomographic data collection from cryo-preserved cells, including large mammalian cells. During data collection the specimen is illuminated with ‘water window’ X-rays (284–543 eV). Illuminating photons are attenuated an order of magnitude more strongly by biomolecules than by water. Consequently, differences in molecular composition generate quantitative contrast in images of the specimen. Soft X-ray tomography is an information-rich three-dimensional imaging method that can be applied either as a standalone technique or as a component modality in correlative imaging studies. PMID:25343808

  17. National Synchrotron Light Source

    ScienceCinema

    BNL

    2016-07-12

    A tour of Brookhaven's National Synchrotron Light Source (NSLS), hosted by Associate Laboratory Director for Light Sources, Stephen Dierker. The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviolet, and x-ray light for basic and applied research in physics, chemistry, medicine, geophysics, environmental, and materials sciences.

  18. The advanced photon source X-ray transmitting beam-position-monitor tests at the national synchrotron light source X-25 beamline

    NASA Astrophysics Data System (ADS)

    Shu, D.; Collins, J. T.; Barraza, J.; Kuzay, T. M.

    1994-08-01

    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.

  19. National Synchrotron Light Source II

    SciTech Connect

    Hill, John; Dooryhee, Eric; Wilkins, Stuart; Miller, Lisa; Chu, Yong

    2016-04-25

    NSLS-II is a synchrotron light source helping researchers explore solutions to the grand energy challenges faced by the nation, and open up new regimes of scientific discovery that will pave the way to discoveries in physics, chemistry, and biology — advances that will ultimately enhance national security and help drive the development of abundant, safe, and clean energy technologies.

  20. National Synchrotron Light Source II

    ScienceCinema

    Hill, John; Dooryhee, Eric; Wilkins, Stuart; Miller, Lisa; Chu, Yong

    2016-07-12

    NSLS-II is a synchrotron light source helping researchers explore solutions to the grand energy challenges faced by the nation, and open up new regimes of scientific discovery that will pave the way to discoveries in physics, chemistry, and biology — advances that will ultimately enhance national security and help drive the development of abundant, safe, and clean energy technologies.

  1. Fifth generation light sources

    NASA Astrophysics Data System (ADS)

    Romaniuk, Ryszard S.

    2016-12-01

    Coherent light sources are one of the most fundamental research tools in biology, technology and in other areas. Synchrotron light source consists of a few basic parts: energy source - which is an electron beam accelerator, energy converter between electron and photon beams - which is an undulator, and photon user experimental lines. Each of these parts is separately a complex system, which is currently a subject to fast technological development. Future light sources of the fifth generation are based on completely new solutions of these fundamental parts, in comparison with the sources of the previous generations. Energy source is a new generation laser - plasma accelerator with electrical field in the area of multiple GV/m. A miniature undulator is tested in the MEMS technology from new materials. Classical light beam lines, vacuum, and difficult for management and beam distribution, change their meaning in the case of availability of miniature undulators positioned immediately at or even inside the experimental stations. After an introduction concerning the light sources of the previous generations, the article shows current research efforts on the mentioned key components of the fifth generation light sources. In some cases this is a continuation and modernization of the previous technologies, in the majority it is a brave endeavour to apply completely new technologies, like laser - plasma acceleration.

  2. Infrared spectroscopy of laser-irradiated dental hard tissues using the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Fried, Daniel; Breunig, Thomas

    2001-04-01

    FTIR spectroscopy used in the specular reflectance mode is well suited for resolving thermally induced changes in dental hard tissue as a result of laser irradiation. High spatial resolution is achievable with a high brightness synchrotron radiation source such as the ALS at Lawrence Berkeley National Laboratory. IR spectra of modified enamel were acquired after laser ablation using several laser wavelengths from the UV to the mid-IR. Specific areas of laser ablation craters were probed non-destructively with 10-micrometers spatial resolution. The chemical composition of the crater walls deviates markedly from that of hydroxyapatite after Er:YAG and CO2 laser irradiation without added water. New mineral phases were resolved that have not been previously observed using conventional IR spectroscopy.

  3. A bend magnet facility for production and application of circularly polarized soft x rays at the Advanced Light Source (abstract)

    NASA Astrophysics Data System (ADS)

    Bustamante, C.; Chen, C. T.; Sette, F.; Howells, M. R.; Hunt, A. J.; Kim, K. J.; Kincaid, B. M.; Maestre, M. F.; Nygren, D. R.; Wong, M.; Snyder, P. A.; Stern, E. A.

    1992-01-01

    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).

  4. National Synchrotron Light Source

    ScienceCinema

    None

    2016-07-12

    A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

  5. National Synchrotron Light Source

    SciTech Connect

    2009-03-10

    A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

  6. Elliptically polarizing undulator beamline 4.0.1 for magnetic spectroscopy at the Advanced Light Source

    SciTech Connect

    Martynov, V.V.; Young, A.T.; Padmore, H.A.

    1996-08-01

    A beamline for high resolution spectroscopy with elliptically polarized X-rays is described.The working energy range is large, from 20 eV to above 1800 eV. The resolving power is on the order of 10,000 at low energies (20-200 eV) and 6000 at high energies (200-1800 eV). This is achieved using a variable deviation angle plane grating monochromator. A single grating, with one line density and a varying groove depth, is used to cover the entire energy range. The beamline has been designed to operate with either one or two x-ray beams propagating simultaneously through the monochromator and to the experimental station. Switching between polarizations at rates of 0.1 Hz and slower is accomplished in the single beam mode by alternating the output of the elliptically polarized undulator source between left and right polarization. Fast polarization switching, at rates of 100-1000 Hz, is provided in the two beam mode by mechanical chopping between two photon beams, one of which is right circularly polarized, and the other left circularly polarized.

  7. Incoherent Light Sources

    NASA Astrophysics Data System (ADS)

    Bertram, Dietrich; Born, Matthias; Jüstel, Thomas

    Since the invention and industrialization of incandescent lamps at the end radiation of the 19th century electrical lighting has become a commodity in our daily life. Today, incoherent light sources are used for numerous application areas. Major improvements have been achieved over the past decades with respect to lamp efficiency (Fig. 10.1), lifetime and color properties.

  8. Incoherent Light Sources

    NASA Astrophysics Data System (ADS)

    Bertram, Dietrich; Born, Matthias; Jüstel, Thomas

    Since the invention and industrialization of incandescent lamps at the end of the 19th century electrical lighting has become a commodity in our daily life. Today, incoherent light sources are used for numerous application areas. Major improvements have been achieved over the past decades with respect to lamp efficiency Fig. 10.1, lifetime and color properties.

  9. A dedicated superbend x-ray microdiffraction beamline for materials, geo-, and environmental sciences at the advanced light source

    NASA Astrophysics Data System (ADS)

    Kunz, Martin; Tamura, Nobumichi; Chen, Kai; MacDowell, Alastair A.; Celestre, Richard S.; Church, Matthew M.; Fakra, Sirine; Domning, Edward E.; Glossinger, James M.; Kirschman, Jonathan L.; Morrison, Gregory Y.; Plate, Dave W.; Smith, Brian V.; Warwick, Tony; Yashchuk, Valeriy V.; Padmore, Howard A.; Ustundag, Ersan

    2009-03-01

    A new facility for microdiffraction strain measurements and microfluorescence mapping has been built on beamline 12.3.2 at the advanced light source of the Lawrence Berkeley National Laboratory. This beamline benefits from the hard x-radiation generated by a 6 T superconducting bending magnet (superbend). This provides a hard x-ray spectrum from 5 to 22 keV and a flux within a 1 μm spot of ˜5×109 photons/s (0.1% bandwidth at 8 keV). The radiation is relayed from the superbend source to a focus in the experimental hutch by a toroidal mirror. The focus spot is tailored by two pairs of adjustable slits, which serve as secondary source point. Inside the lead hutch, a pair of Kirkpatrick-Baez (KB) mirrors placed in a vacuum tank refocuses the secondary slit source onto the sample position. A new KB-bending mechanism with active temperature stabilization allows for more reproducible and stable mirror bending and thus mirror focusing. Focus spots around 1 μm are routinely achieved and allow a variety of experiments, which have in common the need of spatial resolution. The effective spatial resolution (˜0.2 μm) is limited by a convolution of beam size, scan-stage resolution, and stage stability. A four-bounce monochromator consisting of two channel-cut Si(111) crystals placed between the secondary source and KB-mirrors allows for easy changes between white-beam and monochromatic experiments while maintaining a fixed beam position. High resolution stage scans are performed while recording a fluorescence emission signal or an x-ray diffraction signal coming from either a monochromatic or a white focused beam. The former allows for elemental mapping, whereas the latter is used to produce two-dimensional maps of crystal-phases, -orientation, -texture, and -strain/stress. Typically achieved strain resolution is in the order of 5×10-5 strain units. Accurate sample positioning in the x-ray focus spot is achieved with a commercial laser-triangulation unit. A Si

  10. A dedicated superbend x-ray microdiffraction beamline for materials, geo-, and environmental sciences at the advanced light source

    SciTech Connect

    Advanced Light Source; Kunz, Martin; Tamura, Nobumichi; Chen, Kai; MacDowell, Alastair A.; Celestre, Richard S.; Church, Matthew M.; Fakra, Sirine; Domning, Edward E.; Glossinger, James M.; Kirschman, Jonathan L.; Morrison, Gregory Y.; Plate, Dave W.; Smith, Brian V.; Warwick, Tony; Padmore, Howard A.; Ustundag, Ersan; Yashchuk, Valeriy V.

    2009-03-24

    A new facility for microdiffraction strain measurements and microfluorescence mapping has been built on beamline 12.3.2 at the advanced light source of the Lawrence Berkeley National Laboratory. This beamline benefits from the hard x-radiation generated by a 6 T superconducting bending magnet (superbend) This provides a hard x-ray spectrum from 5 to 22 keV and a flux within a 1 mu m spot of ~;;5x109 photons/ s (0.1percent bandwidth at 8 keV). The radiation is relayed from the superbend source to a focus in the experimental hutch by a toroidal mirror. The focus spot is tailored bytwo pairs of adjustable slits, which serve as secondary source point. Inside the lead hutch, a pair of Kirkpatrick-Baez (KB) mirrors placed in a vacuum tank refocuses the secondary slit source onto the sample position. A new KB-bending mechanism with active temperature stabilization allows for more reproducible and stable mirror bending and thus mirror focusing. Focus spots around 1 um are routinely achieved and allow a variety of experiments, which have in common the need of spatial resolution. The effective spatial resolution (~;;0.2 mu m) is limited by a convolution of beam size, scan-stage resolution, and stage stability. A four-bounce monochromator consisting of two channel-cut Si(111) crystals placed between the secondary source and KB-mirrors allows for easy changes between white-beam and monochromatic experiments while maintaining a fixed beam position. High resolution stage scans are performed while recording a fluorescence emission signal or an x-ray diffraction signal coming from either a monochromatic or a white focused beam. The former allows for elemental mapping, whereas the latter is used to produce two-dimensional maps of crystal-phases, -orientation, -texture, and -strain/stress. Typically achieved strain resolution is in the order of 5x10-5 strain units. Accurate sample positioning in the x-ray focus spot is achieved with a commercial laser-triangulation unit. A Si

  11. A dedicated superbend x-ray microdiffraction beamline for materials, geo-, and environmental sciences at the advanced light source

    SciTech Connect

    Kunz, Martin; Tamura, Nobumichi; MacDowell, Alastair A.; Celestre, Richard S.; Church, Matthew M.; Fakra, Sirine; Domning, Edward E.; Glossinger, James M.; Kirschman, Jonathan L.; Morrison, Gregory Y.; Plate, Dave W.; Smith, Brian V.; Warwick, Tony; Yashchuk, Valeriy V.; Padmore, Howard A.; Chen Kai; Ustundag, Ersan

    2009-03-15

    A new facility for microdiffraction strain measurements and microfluorescence mapping has been built on beamline 12.3.2 at the advanced light source of the Lawrence Berkeley National Laboratory. This beamline benefits from the hard x-radiation generated by a 6 T superconducting bending magnet (superbend). This provides a hard x-ray spectrum from 5 to 22 keV and a flux within a 1 {mu}m spot of {approx}5x10{sup 9} photons/s (0.1% bandwidth at 8 keV). The radiation is relayed from the superbend source to a focus in the experimental hutch by a toroidal mirror. The focus spot is tailored by two pairs of adjustable slits, which serve as secondary source point. Inside the lead hutch, a pair of Kirkpatrick-Baez (KB) mirrors placed in a vacuum tank refocuses the secondary slit source onto the sample position. A new KB-bending mechanism with active temperature stabilization allows for more reproducible and stable mirror bending and thus mirror focusing. Focus spots around 1 {mu}m are routinely achieved and allow a variety of experiments, which have in common the need of spatial resolution. The effective spatial resolution ({approx}0.2 {mu}m) is limited by a convolution of beam size, scan-stage resolution, and stage stability. A four-bounce monochromator consisting of two channel-cut Si(111) crystals placed between the secondary source and KB-mirrors allows for easy changes between white-beam and monochromatic experiments while maintaining a fixed beam position. High resolution stage scans are performed while recording a fluorescence emission signal or an x-ray diffraction signal coming from either a monochromatic or a white focused beam. The former allows for elemental mapping, whereas the latter is used to produce two-dimensional maps of crystal-phases, -orientation, -texture, and -strain/stress. Typically achieved strain resolution is in the order of 5x10{sup -5} strain units. Accurate sample positioning in the x-ray focus spot is achieved with a commercial laser

  12. High-efficiency in situ resonant inelastic x-ray scattering (iRIXS) endstation at the Advanced Light Source

    NASA Astrophysics Data System (ADS)

    Qiao, Ruimin; Li, Qinghao; Zhuo, Zengqing; Sallis, Shawn; Fuchs, Oliver; Blum, Monika; Weinhardt, Lothar; Heske, Clemens; Pepper, John; Jones, Michael; Brown, Adam; Spucces, Adrian; Chow, Ken; Smith, Brian; Glans, Per-Anders; Chen, Yanxue; Yan, Shishen; Pan, Feng; Piper, Louis F. J.; Denlinger, Jonathan; Guo, Jinghua; Hussain, Zahid; Chuang, Yi-De; Yang, Wanli

    2017-03-01

    An endstation with two high-efficiency soft x-ray spectrographs was developed at Beamline 8.0.1 of the Advanced Light Source, Lawrence Berkeley National Laboratory. The endstation is capable of performing soft x-ray absorption spectroscopy, emission spectroscopy, and, in particular, resonant inelastic soft x-ray scattering (RIXS). Two slit-less variable line-spacing grating spectrographs are installed at different detection geometries. The endstation covers the photon energy range from 80 to 1500 eV. For studying transition-metal oxides, the large detection energy window allows a simultaneous collection of x-ray emission spectra with energies ranging from the O K-edge to the Ni L-edge without moving any mechanical components. The record-high efficiency enables the recording of comprehensive two-dimensional RIXS maps with good statistics within a short acquisition time. By virtue of the large energy window and high throughput of the spectrographs, partial fluorescence yield and inverse partial fluorescence yield signals could be obtained for all transition metal L-edges including Mn. Moreover, the different geometries of these two spectrographs (parallel and perpendicular to the horizontal polarization of the beamline) provide contrasts in RIXS features with two different momentum transfers.

  13. A Beamline for High-Pressure Studies at the Advanced Light Sourcewith a Superconducting Bending Magnet as the Source

    SciTech Connect

    Kunz, Martin; MacDowell, Alastair A.; Caldwell, Wendel A.; Cambie, Daniella; Celestre, Richard S.; Domning, Edward E.; Duarte,Robert M.; Gleason, Arianna E.; Glossinger, James M.; Kelez, Nicholas; Plate, David W.; Yu, Tony; Zaug, Joeseph M.; Padmore, Howard A.; Jeanloz,Raymond; Alivisatos, A. Paul; Clark, Simon M.

    2005-06-30

    A new facility for high-pressure diffraction andspectroscopy using diamond anvil high-pressure cells has been built atthe Advanced Light Source on Beamline 12.2.2. This beamline benefits fromthe hard X-radiation generated by a 6 Tesla superconducting bendingmagnet (superbend). Useful x-ray flux is available between 5 keV and 35keV. The radiation is transferred from the superbend to the experimentalenclosure by the brightness preserving optics of the beamline. Theseoptics are comprised of: a plane parabola collimating mirror (M1),followed by a Kohzu monochromator vessel with a Si(111) crystals (E/DE ~;7000) and a W/B4C multilayers (E/DE ~; 100), and then a toroidal focusingmirror (M2) with variable focusing distance. The experimental enclosurecontains an automated beam positioning system, a set of slits, ionchambers, the sample positioning goniometry and area detectors (CCD orimage-plate detector). Future developments aim at the installation of asecond end station dedicated for in situ laser-heating on one hand and adedicated high-pressure single-crystal station, applying bothmonochromatic as well as polychromatic techniques.

  14. A Beamline for High-Pressure Studies at the Advanced Light Sourcewith a Superconducting Bending Magnet as the Source

    SciTech Connect

    Kunz, Martin; MacDowell, Alastair A.; Caldwell, Wendel A.; Cambie, Daniella; Celestre, Richard S.; Domning, Edward E.; Duarte,Robert M.; Gleason, Arianna E.; Glossinger, James M.; Kelez, Nicholas; Plate, David W.; Yu, Tony; Zaug, Joeseph M.; Padmore, Howard A.; Jeanloz,Raymond; Alivisatos, A. Paul; Clark, Simon M.

    2005-06-30

    A new facility for high-pressure diffraction and spectroscopy using diamond anvil high-pressure cells has been built at the Advanced Light Source on Beamline 12.2.2. This beamline benefits from the hard X-radiation generated by a 6 Tesla superconducting bending magnet (superbend). Useful x-ray flux is available between 5 keV and 35 keV. The radiation is transferred from the superbend to the experimental enclosure by the brightness preserving optics of the beamline. These optics are comprised of: a plane parabola collimating mirror (M1), followed by a Kohzu monochromator vessel with a Si(111) crystals (E/DE {approx}7000) and a W/B4C multilayers (E/DE {approx} 100), and then a toroidal focusing mirror (M2) with variable focusing distance. The experimental enclosure contains an automated beam positioning system, a set of slits, ion chambers, the sample positioning goniometry and area detectors (CCD or image-plate detector). Future developments aim at the installation of a second end station dedicated for in situ laser-heating on one hand and a dedicated high-pressure single-crystal station, applying both monochromatic as well as polychromatic techniques.

  15. Further development of soft X-ray scanning microscopy with anelliptical undulator at the Advanced Light Source

    SciTech Connect

    Warwick, Tony; Ade, Harald; Fakra, Sirine; Gilles, Mary; Hitchcock, Adam; Kilcoyne, David; Shuh, David; Tyliszczak, Tolek

    2003-04-02

    Soft x-ray scanning microscopy (1) is under continuing development at the Advanced Light Source. Significant progress has been made implementing new scan control systems in both operational microscopes (2) and they now operate at beam lines 5.3.2 and 11.0.2 with interferometer servo scanning and stabilization. The interferometer servo loop registers the images on a universal x/y coordinate system and locks the x-ray spot on selected features for spectro-microscopic studies. At the present time zone plates are in use with 35nm outer zone width and the imaging spatial resolution is at the diffraction limit of these lenses. Current research programs are underway in areas of polymer chemistry, environmental chemistry and materials science. A dedicated polymer STXM is in operation on a bend magnet beam line (4) and is the subject of a separate article (3) in this issue. Here we focus on the capabilities of STXM at a new beam line that employs an elliptical undulator (5) to give control of the polarization of the x-ray beam. This facility is in the process of commissioning and some results are available, other capabilities will be developed during the first half of 2003.

  16. MEMS Incandescent Light Source

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret; King, Kevin; Kim, Lynn; Hansler, Richard; Jones, Eric; George, Thomas

    2001-01-01

    A MEMS-based, low-power, incandescent light source is being developed. This light source is fabricated using three bonded chips. The bottom chip consists of a reflector on Silicon, the middle chip contains a Tungsten filament bonded to silicon and the top layer is a transparent window. A 25-micrometer-thick spiral filament is fabricated in Tungsten using lithography and wet-etching. A proof-of-concept device has been fabricated and tested in a vacuum chamber. Results indicate that the filament is electrically heated to approximately 2650 K. The power required to drive the proof-of-concept spiral filament to incandescence is 1.25 W. The emitted optical power is expected to be approximately 1.0 W with the spectral peak at 1.1 microns. The micromachining techniques used to fabricate this light source can be applied to other MEMS devices.

  17. The Advanced Light Source at Lawrence Berkeley Laboratory: A high-brightness soft x-ray synchrotron-radiation facility

    SciTech Connect

    Schlachter, A.S.; Robinson, A.L.

    1990-07-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Based on a low-emittance electron storage ring optimized to operate at 1.5 GeV, the ALS will have 10 long straight sections available for insertion devices (undulators and wigglers) and 24 high-quality bend-magnet ports. The short pulse width (30--50 ns) will be ideal for time-resolved measurements. Undulators will generate high-brightness soft x-ray and ultraviolet (XUV) radiation from below 20 eV to above 2 keV. Wigglers and bend magnets will extend the spectrum by generating high fluxes of hard x-rays to photon energies above 10 keV. The ALS will support an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms. The high brightness will open new areas of research in the materials sciences, such as spatially resolved spectroscopy (spectromicroscopy). Biological applications will include x-ray microscopy with element-specific sensitivity in the water window of the spectrum where water is much more transparent than protein. The ALS will be an excellent research tool for atomic physics and chemistry because the high flux will allow measurements to be made with tenuous gas-phase targets. 8 refs., 7 figs., 3 tabs.

  18. Analysis of stray radiation produced by the advanced light source (1.9 GeV synchrotron radiation source) at Lawrence Berkeley Laboratory

    SciTech Connect

    Ajemian, Robert C.

    1995-01-01

    The yearly environmental dose equivalent likely to result at the closest site boundary from the Advanced Light Source was determined by generating multiple linear regressions. The independent variables comprised quantified accelerator operating parameters and measurements from synchronized, in-close (outside shielding prior to significant atmospheric scattering), state-of-the-art neutron remmeters and photon G-M tubes. Neutron regression models were more successful than photon models due to lower relative background radiation and redundant detectors at the site boundary. As expected, Storage Ring Beam Fill and Beam Crashes produced radiation at a higher rate than gradual Beam Decay; however, only the latter did not include zero in its 95% confidence interval. By summing for all three accelerator operating modes, a combined yearly DE of 4.3 mRem/yr with a 90% CI of (0.04-8.63) was obtained. These results fall below the DOE reporting level of 10 mRem/yr and suggest repeating the study with improved experimental conditions.

  19. The advanced neutron source

    SciTech Connect

    Raman, S.; Hayter, J.B.

    1990-01-01

    The Advanced Neutron Source (ANS) is a new user experimental facility planned to be operational at Oak Ridge in the late 1990's. The centerpiece of the ANS will be a steady-state research reactor of unprecedented thermal neutron flux ({phi}{sub th} {approx} 8 {times} 10{sup 19} m{sup {minus}2} {center dot}s{sup {minus}1}) accompanied by extensive and comprehensive equipment and facilities for neutron-based research.

  20. The Advanced Neutron Source

    SciTech Connect

    Hayter, J.B.

    1989-01-01

    The Advanced Neutron Source (ANS) is a new user experimental facility planned to be operational at Oak Ridge in the late 1990's. The centerpiece of the ANS will be a steady-state research reactor of unprecedented thermal neutron flux ({phi}{sub th} {approx} 9{center dot}10{sup 19} m{sup -2}{center dot}s{sup -1}) accompanied by extensive and comprehensive equipment and facilities for neutron-based research. 5 refs., 5 figs.

  1. Design, fabrication, and calibration of curved integral coils for measuring transfer function, uniformity, and effective length of LBL ALS (Lawrence Berkeley Laboratory Advanced Light Source) Booster Dipole Magnets

    SciTech Connect

    Green, M.I.; Nelson, D.; Marks, S.; Gee, B.; Wong, W.; Meneghetti, J.

    1989-03-01

    A matched pair of curved integral coils has been designed, fabricated and calibrated at Lawrence Berkeley Laboratory for measuring Advanced Light Source (ALS) Booster Dipole Magnets. Distinctive fabrication and calibration techniques are described. The use of multifilar magnet wire in fabrication integral search coils is described. Procedures used and results of AC and DC measurements of transfer function, effective length and uniformity of the prototype booster dipole magnet are presented in companion papers. 8 refs.

  2. Recent Advances in Lighting Science

    NASA Astrophysics Data System (ADS)

    Lapatovich, Walter P.

    2004-10-01

    Lighting is a global industry supplying a wide array of devices and systems that emit light ranging from incandescent lamps to light emitting diodes to electric discharge lamps. Electric discharge lamps are the most familiar plasma devices to most people. This work focuses on plasma light sources, some advances in this area and recent trends. Plasma light sources fall into two broad categories, namely low pressure and high pressure. The low-pressure lamps operate in the range of 40 to 500 Pa while the high-pressure lamps operate in the range of 0.1 to 15 MPa. The corresponding electron temperatures are about 1eV and 0.5 eV for the low and high-pressure lamps respectively. High-pressure lamps are treated under the assumption of local thermodynamic equilibrium wherein the gas temperature is equilibrated with the electron temperature. They are often called high intensity discharge lamps because of their intrinsically high radiance. Within these two broad categories are many subgroups, perhaps the most important being mercury and non-mercury containing lamps. An example of a low pressure, mercury-containing lamp is the ubiquitous fluorescent lamp. Attempts to improve the efficiency of these lamps center around inductive excitation techniques and two-photon phosphor development. The plasma research on mercury-free low-pressure lamps is focused on finding substitutes for a mercury-rare gas discharge. Several ultraviolet emitting candidates have been explored which emit both UV and visible. Longer wavelength UV is of interest because of the parallel development of phosphors mated with LED excitation wavelengths around 380nm. Several examples will be discussed. There have been major advances in high intensity discharge lamps with and without mercury. Mercury containing metal halide lamps are now being fabricated from translucent ceramic envelopes instead of the conventional vitreous silica. The higher temperature tolerant envelope materials permit using discharges in

  3. Control and acquisition systems for new scanning transmission x-ray microscopes at Advanced Light Source (abstract)

    NASA Astrophysics Data System (ADS)

    Tyliszczak, T.; Hitchcock, P.; Kilcoyne, A. L. D.; Ade, H.; Hitchcock, A. P.; Fakra, S.; Steele, W. F.; Warwick, T.

    2002-03-01

    Two new scanning x-ray transmission microscopes are being built at beamline 5.3.2 and beamline 7.0 of the Advanced Light Source that have novel aspects in their control and acquisition systems. Both microscopes use multiaxis laser interferometry to improve the precision of pixel location during imaging and energy scans as well as to remove image distortions. Beam line 5.3.2 is a new beam line where the new microscope will be dedicated to studies of polymers in the 250-600 eV energy range. Since this is a bending magnet beam line with lower x-ray brightness than undulator beam lines, special attention is given to the design not only to minimize distortions and vibrations but also to optimize the controls and acquisition to improve data collection efficiency. 5.3.2 microscope control and acquisition is based on a PC computer running WINDOWS 2000. All mechanical stages are moved by stepper motors with rack mounted controllers. A dedicated counter board is used for counting and timing and a multi-input/output board is used for analog acquisition and control of the focusing mirror. A three axis differential laser interferometer is being used to improve stability and precision by careful tracking of the relative positions of the sample and zone plate. Each axis measures the relative distance between a mirror placed on the sample stage and a mirror attached to the zone plate holder. Agilent Technologies HP 10889A servo-axis interferometer boards are used. While they were designed to control servo motors, our tests show that they can be used to directly control the piezo stage. The use of the interferometer servo-axis boards provides excellent point stability for spectral measurements. The interferometric feedback also provides active vibration isolation which reduces deleterious impact of mechanical vibrations up to 20-30 Hz. It also can improve the speed and precision of image scans. Custom C++ software has been written to provide user friendly control of the microscope

  4. Solid-state laser source of narrowband ultraviolet B light for skin disease care with advanced performance

    NASA Astrophysics Data System (ADS)

    Tarasov, Aleksandr A.; Chu, Hong; Buchwald, Kristian

    2015-02-01

    Two years ago we reported about the development of solid state laser source for medical skin treatment with wavelength 310.6 nm and average power 200 mW. Here we describe the results of investigation of the advanced version of the laser, which is a more compact device with increased output power and flat top beam profile. Ti: Sapphire laser, the main module of our source, was modified and optimized such, that UV average power of the device was increased 1.7 times. Fiber optic homogenizer was replaced by articulated arm with diffraction diffuser, providing round spot with flat profile at the skin. We investigated and compare characteristics of Ti: Sapphire lasers with volume Bragg grating and with fused silica transmission grating, which was used first time for Ti: Sapphire laser spectral selection and tuning. Promising performance of last gratings is demonstrated.

  5. The Advanced Photon Source

    SciTech Connect

    Galayda, John N.

    1996-01-01

    The Advanced Photon Source (APS) is a 7-GeV third-generation synchrotron radiation storage ring and full-energy positron injector. Construction project funding began in 1989, and ground breaking took place on 5 May 1990. Construction of all accelerator facilities was completed in January 1995 and storage ring commissioning is underway. First observation of x-rays from a bending magnet source took place on 26 March 1995. Nearly all performance specifications of the injector have been reached, and first observations indicate that the reliability, dynamic aperture, emittance, and orbit stability in the storage ring are satisfactory. Observation of radiation from the first of 20 insertion device beamlines is scheduled for October 1995. Start of regular operations is expected to take place well before the APS Project target date of December 1996.

  6. The advanced photon source

    SciTech Connect

    Galayda, J.N.

    1995-07-01

    The Advanced Photon Source (APS) is a 7-GeV third-generation synchrotron radiation storage ring and full-energy positron injector. Construction project funding began in 1989, and ground breaking took place on 5 May 1990. Construction of all accelerator facilities was completed in January 1995 and storage ring commissioning is underway. First observation of x-rays from a bending magnet source took place on 26 March 1995. Nearly all performance specifications of the injector have been reached, and first observations indicate that the reliability, dynamic aperture, emittance, and orbit stability in the storage ring are satisfactory. Observation of radiation from the first of 20 insertion device beamlines is scheduled for October 1995. Start of regular operations is expected to take place well before the APS Project target date of December 1996.

  7. Lasers and Coherent Light Sources

    NASA Astrophysics Data System (ADS)

    Svelto, Orazio; Longhi, Stefano; Della Valle, Giuseppe; Huber, Günter; Kück, Stefan; Pollnau, Markus; Hillmer, Hartmut; Kusserow, Thomas; Engelbrecht, Rainer; Rohlfing (deceased), Frank; Kaiser, Jeffrey; Malz, Ralf; Marowsky, Gerd; Mann, Klaus; Simon, Peter; Rhodes, Charles K.; Duarte, Frank J.; Borsutzky, Annette; L'Huillier, Johannes A.; Sigrist, Markus W.; Wächter, Helen; Saldin, Evgeny; Schneidmiller, Evgeny; Yurkov, Mikhail; Sauerbrey, Roland; Hein, Joachim; Gianella, Michele; Helmcke, Jürgen; Midorikawa, Katsumi; Riehle, Fritz; Steinberg, Steffen; Brand, Hans

    This chapter describes lasers and other sources of coherent light that operate in a wide wavelength range. First, the general principles for the generation of coherent continuous-wave and pulsed radiation are treated including the interaction of radiation with matter, the properties of optical resonators and their modes as well as such processes as Q-switching and mode-locking. The general introduction is followed by sections on numerous types of lasers, the emphasis being on today's most important sources of coherent light, in particular on solid-state lasers and several types of gas lasers. An important part of the chapter is devoted to the generation of coherent radiation coherent radiation by nonlinear processes with optical parametric oscillators, difference- and sum-frequency generation, and high-order harmonics. Radiation in the extended ultraviolet (EUV) and x-ray ranges can be generated by free electron lasers (FEL) and advanced x-ray sources. Ultrahigh light intensities up to 1021 W/cm2 open the door to studies of relativistic laser-matter interaction and laser particle acceleration. The chapter closes with a section on laser stabilization.

  8. Lasers and Coherent Light Sources

    NASA Astrophysics Data System (ADS)

    Svelto, Orazio; Longhi, Stefano; Valle, Giuseppe; Kück, Stefan; Huber, Günter; Pollnau, Markus; Hillmer, Hartmut; Hansmann, Stefan; Engelbrecht, Rainer; Brand, Hans; Kaiser, Jeffrey; Peterson, Alan; Malz, Ralf; Steinberg, Steffen; Marowsky, Gerd; Brinkmann, Uwe; Lo, Dennis; Borsutzky, Annette; Wächter, Helen; Sigrist, Markus; Saldin, Evgeny; Schneidmiller, Evgeny; Yurkov, Mikhail; Midorikawa, Katsumi; Hein, Joachim; Sauerbrey, Roland; Helmcke, Jürgen

    This chapter describes lasers and other sources of coherent light that operate in a wide wavelength range. First, the general principles for the generation of coherent continuous-wave and pulsed radiation are treated including the interaction of radiation with matter, the properties of optical resonators and their modes as well as such processes as Q-switching and mode-locking. The general introduction is followed by sections on numerous types of lasers, the emphasis being on today's most important sources of coherent light, in particular on solid-state lasers and several types of gas lasers. An important part of the chapter is devoted to the generation of coherent radiation by nonlinear processes with optical parametric oscillators, difference- and sum-frequency generation, and high-order harmonics. Radiation in the extended ultraviolet (EUV) and X-ray ranges can be generated by free electron lasers (FEL) and advanced X-ray sources. Ultrahigh light intensities up to 1021 W/cm2 open the door to studies of relativistic laser-matter interaction and laser particle acceleration. The chapter closes with a section on laser stabilization.

  9. Advanced process characterization of a 10nm Metal 1 Logic layer using light source modulation and monitoring

    NASA Astrophysics Data System (ADS)

    Alagna, Paolo; Zurita, Omar; Timoshkov, Vadim; Wong, Patrick; Rechtsteiner, Greg; Baselmans, Jan; Mailfert, Julien; Conley, Will; Hsieh, Simon

    2015-09-01

    As ArF immersion lithography continues to be extended by adopting multi-patterning techniques, imaging requirements continue to become more stringent [1-3]. For multiple patterning based logic devices, the optimal printability is not only driven by the optimization of the optical proximity correction (OPC), but also by complex process factors, such as resist, exposure tool, and mask-related error performance levels. In addition the light source plays a crucial role; it has been widely demonstrated [4-8] how changes in the E95 bandwidth can significantly lead to changes in on wafer patterning due image contrast changes. Cymer has developed novel computational and experimental approaches to enable process characterization studies [9-11]. Using these techniques, simulations were used to assess how E95 bandwidth changes can erode the CDU budget on ≤ 20 nm logic features. Using the results of these simulations, experimental conditions were defined to study the on wafer impact of light source performance on an imec N10 Logic-type test vehicle via six different Metal 1 Logic features. The imaging metrics used to track patterning response are process window (PW), line width roughness (LWR), and local critical dimension uniformity (LCDU).

  10. Nitride quantum light sources

    NASA Astrophysics Data System (ADS)

    Zhu, T.; Oliver, R. A.

    2016-02-01

    Prototype nitride quantum light sources, particularly single-photon emitters, have been successfully demonstrated, despite the challenges inherent in this complex materials system. The large band offsets available between different nitride alloys have allowed device operation at easily accessible temperatures. A wide range of approaches has been explored: not only self-assembled quantum dot growth but also lithographic methods for site-controlled nanostructure formation. All these approaches face common challenges, particularly strong background signals which contaminate the single-photon stream and excessive spectral diffusion of the quantum dot emission wavelength. If these challenges can be successfully overcome, then ongoing rapid progress in the conventional III-V semiconductors provides a roadmap for future progress in the nitrides.

  11. A compact, coherent light source system architecture

    NASA Astrophysics Data System (ADS)

    Biedron, S. G.; Dattoli, G.; DiPalma, E.; Einstein, J.; Milton, S. V.; Petrillo, V.; Rau, J. V.; Sabia, E.; Spassovsky, I. P.; van der Slot, P. J. M.

    2016-09-01

    Our team has been examining several architectures for short-wavelength, coherent light sources. We are presently exploring the use and role of advanced, high-peak power lasers for both accelerating the electrons and generating a compact light source with the same laser. Our overall goal is to devise light sources that are more accessible by industry and in smaller laboratory settings. Although we cannot and do not want to compete directly with sources such as third-generation light sources or that of national-laboratory-based free-electron lasers, we have several interesting schemes that could bring useful and more coherent, short-wavelength light source to more researchers. Here, we present and discuss several results of recent simulations and our future steps for such dissemination.

  12. A Soft X-Ray Undulator Beamline at the Advanced Light Source with Circular and Variable Linear Polarization for the Spectroscopy and Microscopy of Magnetic Materials

    NASA Astrophysics Data System (ADS)

    Young, Anthony T.; Arenholz, Elke; Feng, Jun; Padmore, Howard; Marks, Steve; Schlueter, Ross; Hoyer, Egon; Kelez, Nicholas; Steier, Christoph

    A new undulator beamline at the Advanced Light Source, Lawrence Berkeley National Laboratory is described. This new beamline has an Apple II type undulator which produces linearly and elliptically polarized X-rays. A high resolution monochromator directs the radiation to two branchlines. The first branchline is optimized for spectroscopy and accommodates multiple endstations simultaneously. The second branchline features a photoemission electron microscope. A novel feature of the beamline is the ability to produce linearly polarized radiation at arbitrary, user-selectable angles. Applications of the new beamline are also described.

  13. The Linac Coherent Light Source

    DOE PAGES

    White, William E.; Robert, Aymeric; Dunne, Mike

    2015-05-01

    The Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory was the first hard X-ray free-electron laser (FEL) to operate as a user facility. After five years of operation, LCLS is now a mature FEL user facility. Our personal views about opportunities and challenges inherent to these unique light sources are discussed.

  14. The Linac Coherent Light Source

    PubMed Central

    White, William E.; Robert, Aymeric; Dunne, Mike

    2015-01-01

    The Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory was the first hard X-ray free-electron laser (FEL) to operate as a user facility. After five years of operation, LCLS is now a mature FEL user facility. Our personal views about opportunities and challenges inherent to these unique light sources are discussed. PMID:25931055

  15. The SAGA Light Source

    SciTech Connect

    Yoshida, K.; Iwasaki, Y.; Koda, S.; Okajima, S.; Setoyama, H.; Takabayashi, Y.; Tomimasu, T.; Yoshimura, D.; Ohgaki, H.

    2007-01-19

    Saga prefectural government operates a synchrotron light facility mainly for industrial applications of the synchrotron light. The facility comprises a 1.4 GeV storage ring, a 250 MeV linac as an electron injector and beamlines. The lattice of the storage ring is designed to perform as small emittance as 25 nm-radian and has long straight sections of 2.9 m length for installing insertion devices. Three beam lines have been prepared by Saga prefectural government and one by Saga University.

  16. Light Sources and Ballast Circuits

    NASA Astrophysics Data System (ADS)

    Yorifuji, Takashi; Sakai, Makoto; Yasuda, Takeo; Maehara, Akiyoshi; Okada, Atsunori; Gouriki, Takeshi; Mannami, Tomoaki

    discharge models were reported. Further, studies on ultra high-pressure mercury lamps as light sources for projectors are becoming the mainstream of HID lamp related researches. For high-pressure sodium lamps, many studies on plant growing and pest control utilizing low insect attracting aspects were also reported in 2006. Additionally, for discharge lamps, the minimum sustaining electric power for arc tubes employed in electrode-less compact fluorescent lamps was investigated. For Hg-free rare-gas fluorescent lamps, a luminance of 10,000cd/m2 was attained by a 1 meter-long external duplex spiral electrode prototype using Xe/Ne barrier discharge. As to startup circuits, the commercialization of energy saving and high value added products mainly associated with fluorescent lamps and HID lamps are becoming common. Further, the miniaturization of startup circuits for self electronic-ballasted lamps has advanced. Speaking of the overall light sources and startup circuits in 2006 and with the enforcement of RoHS in Europe in July, the momentum toward hazardous substance-free and energy saving initiatives has been enhanced from the perspective of protecting the global environment. It is anticipated that similar restrictions will be globally enforced in the future.

  17. Fusion pumped light source

    DOEpatents

    Pappas, Daniel S.

    1989-01-01

    Apparatus is provided for generating energy in the form of light radiation. A fusion reactor is provided for generating a long, or continuous, pulse of high-energy neutrons. The neutron flux is coupled directly with the lasing medium. The lasing medium includes a first component selected from Group O of the periodic table of the elements and having a high inelastic scattering cross section. Gamma radiation from the inelastic scattering reactions interacts with the first component to excite the first component, which decays by photon emission at a first output wavelength. The first output wavelength may be shifted to a second output wavelength using a second liquid component responsive to the first output wavelength. The light outputs may be converted to a coherent laser output by incorporating conventional optics adjacent the laser medium.

  18. Implementation and performance of SIBYLS: a dual endstation small-angle X-ray scattering and macromolecular crystallography beamline at the Advanced Light Source

    PubMed Central

    Classen, Scott; Hura, Greg L.; Holton, James M.; Rambo, Robert P.; Rodic, Ivan; McGuire, Patrick J.; Dyer, Kevin; Hammel, Michal; Meigs, George; Frankel, Kenneth A.; Tainer, John A.

    2013-01-01

    The SIBYLS beamline (12.3.1) of the Advanced Light Source at Lawrence Berkeley National Laboratory, supported by the US Department of Energy and the National Institutes of Health, is optimized for both small-angle X-ray scattering (SAXS) and macromolecular crystallography (MX), making it unique among the world’s mostly SAXS or MX dedicated beamlines. Since SIBYLS was commissioned, assessments of the limitations and advantages of a combined SAXS and MX beamline have suggested new strategies for integration and optimal data collection methods and have led to additional hardware and software enhancements. Features described include a dual mode monochromator [containing both Si(111) crystals and Mo/B4C multilayer elements], rapid beamline optics conversion between SAXS and MX modes, active beam stabilization, sample-loading robotics, and mail-in and remote data collection. These features allow users to gain valuable insights from both dynamic solution scattering and high-resolution atomic diffraction experiments performed at a single synchrotron beamline. Key practical issues considered for data collection and analysis include radiation damage, structural ensembles, alternative conformers and flexibility. SIBYLS develops and applies efficient combined MX and SAXS methods that deliver high-impact results by providing robust cost-effective routes to connect structures to biology and by performing experiments that aid beamline designs for next generation light sources. PMID:23396808

  19. Third-generation synchrotron light sources

    SciTech Connect

    Schlachter, A.S.; Wuilleumier, F.J.

    1993-09-01

    X rays are a powerful probe of matter because they interact with electrons in atoms, molecules, and solids. They are commonly produced by relativistic electrons or positrons stored in a synchrotron. Recent advances in technology are leading to the development of a new third generation of synchrotron radiation sources that produce vacuum-ultraviolet and x-ray beams of unprecedented brightness. These new sources are characterized by a very low electron-beam emittance and by long straight sections to accommodate permanent-magnet undulators and wigglers. Several new low-energy light sources, including the Advanced Light Source, presently under construction at the Lawrence Berkeley Laboratory, and ELETTRA, presently being constructed in Trieste, will deliver the world`s brightest synchrotron radiation in the VUV and soft x-ray regions of the spectrum. Applications include atomic and molecular physics and chemistry, surface and materials science, microscopy, and life sciences.

  20. Four Reflector VUV Quarter-wave Retarder of the Beamline 10.0.2 of the Advanced Light Source to Study Angular Momentum Sharing in Atoms

    NASA Astrophysics Data System (ADS)

    Yenen, O.; Jaecks, D. H.; McLaughlin, K. W.; Snell, G.

    2000-06-01

    We have installed, calibrated and characterized a quarter-wave retarder to transform linearly polarized synchrotron radiation into circularly polarized radiation. The quarter-wave retarder based on earlier suggestions and prototypes is built at the Physical Sciences Laboratory, Stoughton WI. The retarder is optimized to obtain circularly polarized radiation in the 10-60 eV range. Using a 45 degree reflector gold mirror linear polarization analyzer, we have determined that the retarder produces better than 99.7 % circularly polarized radiation from the linearly polarized VUV radiation in the 35.5 to 37 eV photon energy range typically with 1 % transmission efficiency. The retarder is installed in the High Resolution AMO Beam Line 10.0.2 of the Advanced Light Source, Lawrence-Berkeley National Laboratory, Berkeley, CA. The circularly polarized photons produced by the retarder are used to study relativistic electron-electron interactions in photoionization.

  1. Lithographic measurement of EUV flare in the 0.3-NA Micro ExposureTool optic at the Advanced Light Source

    SciTech Connect

    Cain, Jason P.; Naulleau, Patrick; Spanos, Costas J.

    2005-01-01

    The level of flare present in a 0.3-NA EUV optic (the MET optic) at the Advanced Light Source at Lawrence Berkeley National Laboratory is measured using a lithographic method. Photoresist behavior at high exposure doses makes analysis difficult. Flare measurement analysis under scanning electron microscopy (SEM) and optical microscopy is compared, and optical microscopy is found to be a more reliable technique. In addition, the measured results are compared with predictions based on surface roughness measurement of the MET optical elements. When the fields in the exposure matrix are spaced far enough apart to avoid influence from surrounding fields and the data is corrected for imperfect mask contrast and aerial image proximity effects, the results match predicted values quite well. The amount of flare present in this optic ranges from 4.7% for 2 {micro}m features to 6.8% for 500 nm features.

  2. Synchrotron Light Sources in Developing Countries

    NASA Astrophysics Data System (ADS)

    Winick, Herman; Pianetta, Piero

    2017-01-01

    The more than 50 light sources now in operation around the world include facilities in Brazil, Korea, and Taiwan which started their programs in the 1980's when they were developing countries. They came on line in the 1990's and have since trained hundreds of graduate students locally, without sending them abroad and losing many of them. They have also attracted dozens of mid-career diaspora scientists to return. Their growing user communities have demanded more advanced facilities, leading to the funding of higher performance new light sources that are now coming into operation. Light sources in the developing world now include the following: SESAME in the Middle East which is scheduled to start research in 2017 (www.sesame.org); The African Light Source, in the planning stage (www.africanlightsource.org); and The Mexican Light Source, in the planning stage (http://www.aps.org/units/fip/newsletters/201509/mexico.cfm). See: http://wpj.sagepub.com/content/32/4/92.full.pdf +html; http://www.lightsources.org/press-release/2015/11/20/grenoble-resolutions-mark-historical-step-towards-african-light-source. SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515.

  3. High-resolution beamline 9.3.2 in the energy range 30-1500 eV at the advanced light source: Design and performance

    SciTech Connect

    Hussain, Z.; Heimann, P.A.; McKinney, W.

    1995-12-01

    Bending magnet beamline 9.3.2 at the Advanced Light Source (ALS) was designed for high resolution spectroscopy with capability for delivering circularly polarized light in the soft X-ray energy region using three gratings. The monochromator is a fixed included angle spherical grating monochromator (SGM) and was originally used at SSRL as a prototype for later insertion device based monochromators for the ALS, For operation at the ALS, the toroidal pre-mirror used at SSRL was replaced by a horizontally focusing and a vertically focusing mirrors in the Kirkpatrick-Baez configuration. Circularly polarized radiation is obtained by inserting a water-cooled movable aperture in front of the vertically focusing mirror to allow selecting the beam either above or below the horizontal plane. To maintain a stable beam intensity through the entrance slit, the photocurrent signals from the upper and lower jaws of the entrance slit are utilized to set a feedback loop with the vertically deflecting mirror piezoelectric drive. The beamline end station has a movable platform that accommodates two experimental chambers enabling the synchrotron radiation to be directed to either one of the two experimental chambers without breaking the vacuum.

  4. Synchrotron light source data book

    SciTech Connect

    Murphy, J.

    1989-01-01

    The ''Synchrotron Light Source Data Book'' is as its name implies a collection of data on existing and planned synchrotron light sources. The intention was to provide a compendium of tools for the design of electron storage rings as synchrotron radiation sources. The slant is toward the accelerator physicist as other booklets such as the X-ray Data Booklet, edited by D. Vaughan (LBL PUB-490), address the 'use' of synchrotron radiation. It is hoped that the booklet serves as a pocket sized reference to facilitate back of the envelope type calculations. It contains some useful formulae in 'practical units' and a brief description of many of the existing and planned light source lattices.

  5. Surface-micromachined magnetic undulator with period length between 10μm and 1 mm for advanced light sources

    NASA Astrophysics Data System (ADS)

    Harrison, Jere; Joshi, Abhijeet; Lake, Jonathan; Candler, Rob; Musumeci, Pietro

    2012-07-01

    A technological gap exists between the μm-scale wiggling periods achieved using electromagnetic waves of high intensity laser pulses and the mm scale of permanent-magnet and superconducting undulators. In the sub-mm range, surface-micromachined soft-magnetic micro-electro-mechanical system inductors with integrated solenoidal coils have already experimentally demonstrated 100 to 500 mT field amplitude across air gaps as large as 15μm. Simulations indicate that magnetic fields as large as 1.5 T across 50μm inductor gaps are feasible. A simple rearranging of the yoke and pole geometry allows for fabrication of 10+ cm long undulator structures with period lengths between 12.5μm and 1 mm. Such undulators find application both in high average power spontaneous emission sources and, if used in combination with ultrahigh-brightness electron beams, could lead to the realization of low energy compact free-electron lasers. Challenges include electron energy broadening due to wakefields and Joule heating in the electromagnet.

  6. Understanding Titan's Atmospheric Isotope Inventory through Laboratory Photolysis Experiments using Vacuum Ultraviolet Photons from Advanced Light Source Synchrotron

    NASA Astrophysics Data System (ADS)

    Chakraborty, S.

    2015-12-01

    Titan, Saturn's planet-like moon with a thick atmosphere consists mainly of N2 (98.4 %) and CH4 (1.4%). It is debated whether the N2 is primordial, or the NH3, which later converted to N2 by physic-chemical processes and, if NH3 is primordial, what is the source of that material: Saturnian-subnebula or the comets? N2 is enriched in 15N (14N/15N = 160 compared to 272 for Earth) and in geochemical terminology, d15Nair = 700 ‰ (parts per thousand with respect to ambient air). On the same scale the solar wind and Jupiter's atmosphere are ~ -400 ‰ (depleted in 15N). The comets (NH3 and HCN) and insoluble organic matter in meteorites are also enriched in 15N in the range up to a few thousand ‰. On the contrary, the carbon isotopic ratio in CH4 in Titan is similar to the other solar system bodies (12C/13C~ 89). We have performed extensive low temperature (80 K) photodissociation of N2 and CO (in presence of H2) at VUV wavelengths to measure the isotopic fractionation in the products. The integrated instantaneous fractionation in the product NH3 is about 1000 ‰ over the N2 dissociation regime (80-100 nm), which arise due to quantum mechanical selection rules. CO2 and CH4, the products of CO photodissociation, show contradictory results for two elements. While product O (trapped in CO2) is enriched by few thousand ‰, there is no significant C isotopic enrichment in CH4. These laboratory measurements along with the measurements by Cassini-Huygens spacecraft constrain the origin of volatiles in Titan's atmosphere and indicate that Titan accreted comet-like NH3 and CH4, which are the 1st generation photolysis products (of the remaining materials after the formation of gas giants) in the solar nebula. Later, NH3 converted to N2 in a bulk fashion (within Titan) and retained mostly identical isotopic composition. 15N enrichment measured in HCN in the present day atmosphere (d15Nair > 1500 ‰), is possibly from the 2nd generation N2 photolysis in Titan's modern

  7. Solid-State Spectral Light Source System

    NASA Technical Reports Server (NTRS)

    Maffione, Robert; Dana, David

    2011-01-01

    A solid-state light source combines an array of light-emitting diodes (LEDs) with advanced electronic control and stabilization over both the spectrum and overall level of the light output. The use of LEDs provides efficient operation over a wide range of wavelengths and power levels, while electronic control permits extremely stable output and dynamic control over the output. In this innovation, LEDs are used instead of incandescent bulbs. Optical feedback and digital control are used to monitor and regulate the output of each LED. Because individual LEDs generate light within narrower ranges of wavelengths than incandescent bulbs, multiple LEDs are combined to provide a broad, continuous spectrum, or to produce light within discrete wavebands that are suitable for specific radiometric sensors.

  8. National Synchrotron Light Source II

    ScienceCinema

    Steve Dierker

    2016-07-12

    The National Synchrotron Light Source II (NSLS-II) at the U.S. Department of Energy's Brookhaven National Laboratory is a proposed new state-of-the-art medium energy storage ring designed to deliver world-leading brightness and flux with top-off operation

  9. National Synchrotron Light Source II

    SciTech Connect

    Steve Dierker

    2008-03-12

    The National Synchrotron Light Source II (NSLS-II) at the U.S. Department of Energy's Brookhaven National Laboratory is a proposed new state-of-the-art medium energy storage ring designed to deliver world-leading brightness and flux with top-off operation

  10. The advanced light source at Lawrence Berkeley Laboratory—A high-brightness soft x-ray synchrotron-radiation facility

    NASA Astrophysics Data System (ADS)

    Schlachter, Alfred S.; Robinson, Arthur L.

    1990-12-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory, is scheduled to begin serving qualified users across a broad spectrum of research areas in the spring of 1993. Based on a low-emittance electron storage ring optimized to operate at 1.5 GeV, the ALS will have 10 long straight sections available for insertion devices (undulators and wigglers) and 24 high-quality bend-magnet ports. The short pulse width (30-50 ns) will be ideal for time-resolved measurements. Undulators will generate high-brightness soft x-ray and ultraviolet (XUV) radiation from below 10 eV to above 2 keV. Wigglers and bend magnets will extend the spectrum by generating high fluxes of hard x-rays to photon energies above 10 keV. The ALS will support an extensive research program in which XUV radiation is used to study matter in all its varied gaseous, liquid, and solid forms. The high brightness will open new areas of research in the materials sciences, such as spatially resolved spectroscopy (spectromicroscopy). Biological applications will include x-ray microscopy with element-specific sensitivity in the water window of the spectrum where water is much more transparent than protein. The ALS will be an excellent research tool for atomic physics and chemistry because the high flux will allow measurements to be made with tenuous gas-phase targets.

  11. High resolution soft x-ray bending magnet beamline 9.3.2 with circularly polarized radiation capability at the Advanced Light Source

    SciTech Connect

    Hussain, Z.; Heimann, P.A.; McKinney, W.; Padmore, H.A.; Huff, W.R.A.; Kellar, S.A.; Moler, E.J. |; Fadley, C.S. |; Shirley, D.A.

    1995-08-01

    Bending magnet beamline 9.3.2 at the Advanced Light Source (ALS) was designed for high resolution spectroscopy in the soft x-ray energy region, covering a range from 30 eV to 1500 eV with three gratings. The monochromator itself is a standard fixed included angle 55 m spherical grating monochromator and was originally used at the Stanford Synchrotron Radiation Laboratory (SSRL) as a prototype for later insertion device based monochromators for the ALS. For operations at the ALS, the toroidal pre-mirror used at SSRL to vertically focus onto the entrance slit and horizontally focus onto the exit slit was replaced by two separate crossed mirrors (Kirkpatrick-Baez configuration). Circularly polarized radiation is obtained by inserting a water-cooled movable aperture in front of the vertically focusing mirror to allow selecting the beam either above or below the horizontal plane. To maintain a stable beam intensity through the entrance slit, the photocurrent signals from the upper and lower jaws of the entrance slit are utilized to set a feedback loop with the vertically deflecting mirror Piezoelectric drive. The beamline end station has a rotatable platform (through 60{degree}) that accommodates two experimental chambers, enabling the synchrotron radiation to be directed to either one without breaking vacuum.

  12. Status of the advanced neutron source. [Advanced Neutron Source Reactor

    SciTech Connect

    Hayter, J.B.

    1990-01-01

    Research reactors in the United States are becoming more and more outdated, at a time when neutron scattering is being recognized as an increasingly important technique in areas vital to the US scientific and technological future. The last US research reactor was constructed over 25 years ago, whereas new facilities have been built or are under construction in Japan, Russia and, especially, Western Europe, which now has a commanding lead in this important field. Concern over this situation in the early 1980's by a number of organizations, including the National Academy of Sciences, led to a recommendation that design work start urgently on an advanced US neutron research facility. This recommendation is realized in the Advanced Neutron Source Project. The centerpiece of the Advanced Neutron Source will be a new research reactor of unprecedented flux (>7.5 {times} 10{sup 19} m{sup {minus}2}{center dot}s{sup {minus}1}), equipped with a wide variety of state-of-the-art spectrometers and diffractometers on hot, thermal, and cold neutron beams. Very cold and ultracold neutron beams will also be provided for specialized experiments. This paper will discuss the current status of the design and the plans for scattering instrumentation. 5 refs.

  13. The upgraded scheme of Hefei Light Source

    SciTech Connect

    Li Weimin; Xu Hongliang; Wang Lin; Feng Guangyao; Zhang Shancai; Hao Hao

    2010-06-23

    To enhance the performance of Hefei Light Source, which was designed and constructed two decades ago, an upgrade project would be carried out in the near future. The detail upgrade scheme was described in this paper. Firstly, the magnet lattice of storage ring should be reconstructed with 4 DBA cells, whose advantages are lower beam emittance and more straight section available for insertion devices. Secondly, the beam diagnostics, main power supply, transverse and longitudinal multi-bunch feedback, beam control and manipulation system would be upgrade to improve the beam orbit stability. Finally, the injection system of storage ring and injector, which is composed of electron linac and beam transfer line, would be updated in order to assure smooth beam accumulation process under new low emittance lattice. With above improvement, it is hopeful to increase the brilliance of Hefei Light Source by two orders approximately. After three-year upgrade project, the performance of HLS would meet the demands of advanced SR users.

  14. Photonic crystal light-emitting sources

    NASA Astrophysics Data System (ADS)

    David, Aurélien; Benisty, Henri; Weisbuch, Claude

    2012-12-01

    Photonic crystals (PhCs) are periodically structured optical media offering the opportunity for spontaneous emission (SpE) to be strongly controlled in spatial terms (directions) or in absolute terms (rates). We discuss the application of this concept for practical light-emitting sources, summarizing the principles and actual merits of various approaches based on two- and three-dimensional PhCs. We take into consideration the numerous constraints on real-world light-emitting structures and materials. The various mechanisms through which modified photonic bands and band gaps can be used are first revisited in view of their use in light sources. We then present an in-depth discussion of planar emitters and enhanced extraction of light thanks to grating diffraction. Applications to conventional III-V semiconductors and to III-nitrides are reviewed. Comparison with random surface roughening reveals some common physical limitations. Some advanced approaches with complex structures or etched active structures are also discussed. Finally, the most promising mechanism to enhance the SpE rate, the Purcell effect, is considered. Its implementation, including through plasmonic effects, is shown to be effective only for very specific sources. We conclude by outlining the mix of physics and material parameters needed to grasp the relevant issues.

  15. Light pollution simulations for planar ground-based light sources.

    PubMed

    Kocifaj, Miroslav

    2008-02-20

    The light pollution model is employed to analyze spatial behavior of luminance at the night sky under cloudless and overcast conditions. Enhanced light excess is particularly identified at cloudy skies, because the clouds efficiently contribute to the downward luminous flux. It is evident that size of ground-based light sources can play an important role in the case of overcast sky conditions. Nevertheless, the realistically sized light sources are rarely embedded into light pollution modeling, and rather they are replaced by simple point sources. We discuss the discrepancies between sky luminance distributions when at first the planar light sources are considered and at second the point-source approximation is accepted. The found differences are noticeable if the size of the light source, distance to the observer, and altitude of a cloudy layer are comparable one to the other. Compared with point-source approximation, an inclusion of the size factor into modeling the light sources leads to partial elimination of the steep changes of sky luminance (typical for point sources of light). The narrow and sharp light pillars normally presented on the sky illuminated by point light sources can disappear or fuse together when two or more nearby light sources are considered with their real sizes. Sky elements situated close to the horizon will glow efficiently if luminous flux originates from two-dimensional ground-based entities (such as cities or villages).

  16. Driver circuit for solid state light sources

    DOEpatents

    Palmer, Fred; Denvir, Kerry; Allen, Steven

    2016-02-16

    A driver circuit for a light source including one or more solid state light sources, a luminaire including the same, and a method of so driving the solid state light sources are provided. The driver circuit includes a rectifier circuit that receives an alternating current (AC) input voltage and provides a rectified AC voltage. The driver circuit also includes a switching converter circuit coupled to the light source. The switching converter circuit provides a direct current (DC) output to the light source in response to the rectified AC voltage. The driver circuit also includes a mixing circuit, coupled to the light source, to switch current through at least one solid state light source of the light source in response to each of a plurality of consecutive half-waves of the rectified AC voltage.

  17. Renewal of the Advanced Photon Source.

    SciTech Connect

    Gibson, J. M.

    2008-12-31

    To ensure that state-of-the-art hard x-ray tools are available for US scientists and engineers who are solving key problems in energy, environment, technology development and human health, the nation's unique high-energy x-ray source needs a major renewal of its capabilities. The Advanced Photon Source renewal program responds to key scientific needs driven by our user community. The renewal encompasses many innovations in beamlines and accelerator capabilities, each of which will transform our tools and allow new problems to be solved. In particular the APS renewal dramatically expands two compelling avenues for research. Through x-ray imaging, we can illuminate complex hierarchical structures from the molecular level to the macroscopic level, and study how they change in time and in response to stimuli. Images will facilitate understanding how proteins fit together to make living organisms, contribute to development of lighter, higher-strength alloys for fuel-efficient transportation and advance the use of biomass for alternative fuels. Hard x-rays are also especially suited to the study of real materials, under realistic conditions and in real-time. The advances proposed in this area would help develop more efficient catalysts, enhance green manufacturing, point the way to artificial light-harvesting inspired by biology and help us develop more efficient lighting. The scope of the renewal of our {approx}$1.5B facility is estimated to be {approx}$350M over five years. It is vital that the investment begin as soon as possible. The renewed APS would complement other national investments such as the National Synchrotron Light Source-II and would keep the U.S. internationally competitive.

  18. Advanced lighting guidelines: 1993. Final report

    SciTech Connect

    Eley, C.; Tolen, T.M.; Benya, J.R.; Rubinstein, F.; Verderber, R.

    1993-12-31

    The 1993 Advanced Lighting Guidelines document consists of twelve guidelines that provide an overview of specific lighting technologies and design application techniques utilizing energy-efficient lighting practice. Lighting Design Practice assesses energy-efficient lighting strategies, discusses lighting issues, and explains how to obtain quality lighting design and consulting services. Luminaires and Lighting Systems surveys luminaire equipment designed to take advantage of advanced technology lamp products and includes performance tables that allow for accurate estimation of luminaire light output and power input. The additional ten guidelines -- Computer-Aided Lighting Design, Energy-Efficient Fluorescent Ballasts, Full-Size Fluorescent Lamps, Compact Fluorescent Lamps, Tungsten-Halogen Lamps, Metal Halide and HPS Lamps, Daylighting and Lumen Maintenance, Occupant Sensors, Time Scheduling Systems, and Retrofit Control Technologies -- each provide a product technology overview, discuss current products on the lighting equipment market, and provide application techniques. This document is intended for use by electric utility personnel involved in lighting programs, lighting designers, electrical engineers, architects, lighting manufacturers` representatives, and other lighting professionals.

  19. Advanced Neutron Source enrichment study

    SciTech Connect

    Bari, R.A.; Ludewig, H.; Weeks, J.R.

    1994-12-31

    A study has been performed of the impact on performance of using low enriched uranium (20% {sup 235}U) or medium enriched uranium (35% {sup 235}U) as an alternative fuel for the Advanced Neutron Source, which is currently designed to use uranium enriched to 93% {sup 235}U. Higher fuel densities and larger volume cores were evaluated at the lower enrichments in terms of impact on neutron flux, safety, safeguards, technical feasibility, and cost. The feasibility of fabricating uranium silicide fuel at increasing material density was specifically addressed by a panel of international experts on research reactor fuels. The most viable alternative designs for the reactor at lower enrichments were identified and discussed. Several sensitivity analyses were performed to gain an understanding of the performance of the reactor at parametric values of power, fuel density, core volume, and enrichment that were interpolations between the boundary values imposed on the study or extrapolations from known technology.

  20. New Directions in X-Ray Light Sources

    ScienceCinema

    Falcone, Roger

    2016-07-12

    July 15, 2008 Berkeley Lab lecture: Molecular movies of chemical reactions and material phase transformations need a strobe of x-rays, the penetrating light that reveals how atoms and molecules assemble in chemical and biological systems and complex materials. Roger Falcone, Director of the Advanced Light Source,will discuss a new generation of x ray sources that will enable a new science of atomic dynamics on ultrafast timescales.

  1. New Directions in X-Ray Light Sources

    SciTech Connect

    Falcone, Roger

    2008-07-18

    July 15, 2008 Berkeley Lab lecture: Molecular movies of chemical reactions and material phase transformations need a strobe of x-rays, the penetrating light that reveals how atoms and molecules assemble in chemical and biological systems and complex materials. Roger Falcone, Director of the Advanced Light Source,will discuss a new generation of x ray sources that will enable a new science of atomic dynamics on ultrafast timescales.

  2. EDITORIAL: LED light sources (light for the future) LED light sources (light for the future)

    NASA Astrophysics Data System (ADS)

    Grandjean, N.

    2010-09-01

    comprehensive review of the different localization mechanisms and their implication for internal quantum efficiency (IQE) is proposed by Oliver and co-workers from Cambridge University. When discussing IQE in InGaN-based LEDs, the efficiency droop at high-current injection always emerges, which is a major concern for the future of SSL technology. Here, a collaborative work between Samsung and the Gwangju Institute of Science and Technology (Korea) proves that a specific design of the active region can limit this detrimental effect. Once the issue of the IQE is solved, one still has to let the photons out of the chip. Matioli and Weisbuch from the University of California at Santa Barbara introduce the use of photonic crystals (PhCs) to improve light extraction efficiency. They describe different approaches to overcoming the main limitation of LEDs when implementing surface PhCs. The technology of SSL, and in particular of colour rendering, is tackled by Zukauskas et al who studied in detail different white light sources. They show that extreme colour-fidelity indices need to cover the entire spectrum, with a broad-band at 530-610 nm and a component beyond 610 nm. Then, the reliability of GaN-based LEDs is discussed in the paper of Meneghesso and co-workers. The authors consider the most important physical mechanisms that are (i) the degradation of the active layer of LEDs, (ii) the degradation of the package/phosphor system, (iii) the failure of GaN-based LEDs against electrostatic discharge. Finally, GaN LEDs on silicon developed in the group of Egawa at the Nagoya Institute of Technology are presented. This technology could allow a significant decrease in the fabrication cost of white LEDs.

  3. Photometer for tracking a moving light source

    NASA Technical Reports Server (NTRS)

    Strawa, Anthony W. (Inventor)

    2009-01-01

    A photometer that tracks a path of a moving light source with little or no motion of the photometer components. The system includes a non-moving, truncated paraboloid of revolution, having a paraboloid axis, a paraboloid axis, a small entrance aperture, a larger exit aperture and a light-reflecting inner surface, that receives and reflects light in a direction substantially parallel to the paraboloid axis. The system also includes a light processing filter to receive and process the redirected light, and to issue the processed, redirected light as processed light, and an array of light receiving elements, at least one of which receives and measures an associated intensity of a portion of the processed light. The system tracks a light source moving along a path and produces a corresponding curvilinear image of the light source path on the array of light receiving elements. Undesired light wavelengths from the light source may be removed by coating a selected portion of the reflecting inner surface or another light receiving surface with a coating that absorbs incident light in the undesired wavelength range.

  4. Development of a circadian light source

    NASA Astrophysics Data System (ADS)

    Nicol, David B.; Ferguson, Ian T.

    2002-11-01

    Solid state lighting presents a new paradigm for lighting - controllability. Certain characteristics of the lighting environment can be manipulated, because of the possibility of using multiple LEDs of different emission wavelengths as the illumination source. This will provide a new, versatile, general illumination source due to the ability to vary the spectral power distribution. New effects beyond the visual may be achieved that are not possible with conventional light sources. Illumination has long been the primary function of lighting but as the lighting industry has matured the psychological aspects of lighting have been considered by designers; for example, choosing a particular lighting distribution or color variation in retail applications. The next step in the evolution of light is to consider the physiological effects of lighting that cause biological changes in a person within the environment. This work presents the development of a source that may have important bearing on this area of lighting. A circadian light source has been developed to provide an illumination source that works by modulating its correlated color temperature to mimic the changes in natural daylight through the day. In addition, this source can cause or control physiological effects for a person illuminated by it. The importance of this is seen in the human circadian rhythm's peak response corresponding to blue light at ~460 nm which corresponds to the primary spectral difference in increasing color temperature. The device works by adding blue light to a broadband source or mixing polychromatic light to mimic the variation of color temperature observed for the Planckian Locus on the CIE diagram. This device can have several applications including: a tool for researchers in this area, a general illumination lighting technology, and a light therapy device.

  5. Development of ultrafast laser-based x-ray in-vivo phase-contrast micro-CT beamline for biomedical applications at Advanced Laser Light Source (ALLS).

    PubMed

    Kincaid, Russell; Krol, Andrzej; Fourmaux, Sylvain; Kieffer, Jean-Claude; Serbanescu, Cristina; Servol, Marina; Vogelsang, Levon; Wilkins, Steve; Stevenson, Andrew; Nesterets, Yakov; Lipson, Edward; Ye, Hongwei; Pogany, Andrew

    2008-01-01

    We are developing and exploring the imaging performance of, an in vivo, in-line holography, x-ray phase-contrast, micro-CT system with an ultrafast laser-based x-ray (ULX) source. By testing and refining our system, and by performing computer simulations, we plan to improve system performance in terms of contrast resolution and multi-energy imaging to a level beyond what can be obtained using a conventional microfocal x-ray tube. Initial CT projection sets at single energy (Mo K(alpha) and K(beta) lines) were acquired in the Fresnel regime and reconstructed for phantoms and a euthanized mouse. We also performed computer simulations of phase-contrast micro-CT scans for low-contrast, soft-tissue, tumor imaging. We determined that, in order to perform a phase-contrast, complete micro-CT scan using ULX, the following conditions must be met: (i) the x-ray source needs to be stable during the scan; (ii) the laser focal spot size needs to be less than 10 mum for source-to-object distance greater than 30 cm; (iii) the laser light intensity on the target needs to be in the range of 5 x 10(17) to 5 x 10(19) W/cm(2); (iv) the ablation protection system needs to allow uninterrupted scans; (v) the laser light focusing on the target needs to remain accurate during the entire scan; (vi) a fresh surface of the target must be exposed to consecutive laser shots during the entire scan; (vii) the effective detector element size must be less than 12 mum. Based on the results obtained in this research project, we anticipate that the new 10 Hz, 200 TW laser with 50 W average power that is being commissioned at ALLS will allow us practical implementation of in vivo x-ray phase-contrast micro-CT.

  6. The First Sources of Light

    NASA Astrophysics Data System (ADS)

    Loeb, Avi

    2011-09-01

    Looking deep into the Universe through powerful telescopes, we can see images of the Universe when it was younger because of the finite time it takes light to travel to us from distant sources. Existing data sets include an image of the Universe when it was 0.4 million years old (in the form of the cosmic microwave background), as well as images of individual galaxies when the Universe was older than a billion years. But there is a serious challenge: in between these two epochs was a period when the Universe was dark, stars had not yet formed, and the cosmic microwave background no longer traced the distribution of matter. And this is precisely the most interesting period, when the primordial soup evolved into the rich zoo of objects we now see. The observers are moving ahead along several fronts. The first involves the construction of large infrared telescopes on the ground and in space, that will provide us with new photos of the first galaxies. Current plans include ground-based telescopes which are 24-42 meter in diameter, and NASA's successor to the Hubble Space Telescope, called the James Webb Space Telescope. In addition, several observational groups around the globe are constructing radio arrays that will be capable of mapping the three-dimensional distribution of cosmic hydrogen in the infant Universe. These arrays are aiming to detect the long-wavelength (redshifted 21-cm) radio emission from hydrogen atoms. The images from these antenna arrays will reveal how the non-uniform distribution of neutral hydrogen evolved with cosmic time and eventually was extinguished by the ultra-violet radiation from the first galaxies. Theoretical research has focused in recent years on predicting the expected signals for the above instruments and motivating these ambitious observational projects.

  7. LEDs as light source: examining quality of acquired images

    NASA Astrophysics Data System (ADS)

    Bachnak, Rafic; Funtanilla, Jeng; Hernandez, Jose

    2004-05-01

    Recent advances in technology have made light emitting diodes (LEDs) viable in a number of applications, including vehicle stoplights, traffic lights, machine-vision-inspection, illumination, and street signs. This paper presents the results of comparing images taken by a videoscope using two different light sources. One of the sources is the internal metal halide lamp and the other is a LED placed at the tip of the insertion tube. Images acquired using these two light sources were quantitatively compared using their histogram, intensity profile along a line segment, and edge detection. Also, images were qualitatively compared using image registration and transformation. The gray-level histogram, edge detection, image profile and image registration do not offer conclusive results. The LED light source, however, produces good images for visual inspection by an operator. The paper will present the results and discuss the usefulness and shortcomings of various comparison methods.

  8. Energy Recovery Linacs for Light Source Applications

    SciTech Connect

    George Neil

    2011-04-01

    Energy Recovery Linacs are being considered for applications in present and future light sources. ERLs take advantage of the continuous operation of superconducting rf cavities to accelerate high average current beams with low losses. The electrons can be directed through bends, undulators, and wigglers for high brightness x ray production. They are then decelerated to low energy, recovering power so as to minimize the required rf drive and electrical draw. When this approach is coupled with advanced continuous wave injectors, very high power, ultra-short electron pulse trains of very high brightness can be achieved. This paper will review the status of worldwide programs and discuss the technology challenges to provide such beams for photon production.

  9. Solid-state light sources getting smart.

    PubMed

    Schubert, E Fred; Kim, Jong Kyu

    2005-05-27

    More than a century after the introduction of incandescent lighting and half a century after the introduction of fluorescent lighting, solid-state light sources are revolutionizing an increasing number of applications. Whereas the efficiency of conventional incandescent and fluorescent lights is limited by fundamental factors that cannot be overcome, the efficiency of solid-state sources is limited only by human creativity and imagination. The high efficiency of solid-state sources already provides energy savings and environmental benefits in a number of applications. However, solid-state sources also offer controllability of their spectral power distribution, spatial distribution, color temperature, temporal modulation, and polarization properties. Such "smart" light sources can adjust to specific environments and requirements, a property that could result in tremendous benefits in lighting, automobiles, transportation, communication, imaging, agriculture, and medicine.

  10. Advanced Lighting Program Development (BG9702800) Final Report

    SciTech Connect

    Rubinstein, Francis; Johnson, Steve

    1998-02-01

    The report presents a long-range plan for a broad-based, coordinated research, development and market transformation program for reducing the lighting energy intensities in commercial and residential buildings in California without compromising lighting quality. An effective program to advance lighting energy efficiency in California must be based on an understanding that lighting is a mature field and the lighting industry has developed many specialized products that meet a wide variety of light needs for different building types. Above all else, the lighting field is diverse and there are applications for a wide range of lighting products, systems, and strategies. Given the range of existing lighting solutions, an effective energy efficient lighting research portfolio must be broad-based and diverse to match the diversity of the lighting market itself. The belief that there is one solution--a magic bullet, such as a better lamp, for example--that will propel lighting efficiency across all uses to new heights is, in the authors' opinion, an illusion. A multi-path program is the only effective means to raising lighting efficiency across all lighting applications in all building types. This report presents a list of 27 lighting technologies and concepts (key activities) that could form the basis of a coordinated research and market transformation plan for significantly reducing lighting energy intensities in California buildings. The total 27 key activities into seven broad classes as follows: Light sources; Ballasts; Luminaires; Lighting Controls; Lighting Systems in Buildings; Human Factors and Education. Each of the above technology classes is discussed in terms of background, key activities, and the energy savings potential for the state. The report concludes that there are many possibilities for targeted research, development, and market transformation activities across all sectors of the building lighting industry. A concerted investment by the state to foster

  11. Matrix light and pixel light: optical system architecture and requirements to the light source

    NASA Astrophysics Data System (ADS)

    Spinger, Benno; Timinger, Andreas L.

    2015-09-01

    Modern Automotive headlamps enable improved functionality for more driving comfort and safety. Matrix or Pixel light headlamps are not restricted to either pure low beam functionality or pure high beam. Light in direction of oncoming traffic is selectively switched of, potential hazard can be marked via an isolated beam and the illumination on the road can even follow a bend. The optical architectures that enable these advanced functionalities are diverse. Electromechanical shutters and lens units moved by electric motors were the first ways to realize these systems. Switching multiple LED light sources is a more elegant and mechanically robust solution. While many basic functionalities can already be realized with a limited number of LEDs, an increasing number of pixels will lead to more driving comfort and better visibility. The required optical system needs not only to generate a desired beam distribution with a high angular dynamic, but also needs to guarantee minimal stray light and cross talk between the different pixels. The direct projection of the LED array via a lens is a simple but not very efficient optical system. We discuss different optical elements for pre-collimating the light with minimal cross talk and improved contrast between neighboring pixels. Depending on the selected optical system, we derive the basic light source requirements: luminance, surface area, contrast, flux and color homogeneity.

  12. Light sources currently used in photochemotherapy

    NASA Astrophysics Data System (ADS)

    Kwasńy, Mirosław; Gietka, Andrzej; Kotowski, Paweł; Mierczyk, Zygmunt

    2016-12-01

    The availability of low-cost therapeutic illuminators was one of the key factors to limit clinical use of PDT. The paper presents modern light sources which have revolutionized PDT method, contributing to its more common use. The technical parameters of different illuminators are compared. Finally, own light sources were presented and developed in Polish clinics.

  13. Microwave-driven ultraviolet light sources

    DOEpatents

    Manos, Dennis M.; Diggs, Jessie; Ametepe, Joseph D.

    2002-01-29

    A microwave-driven ultraviolet (UV) light source is provided. The light source comprises an over-moded microwave cavity having at least one discharge bulb disposed within the microwave cavity. At least one magnetron probe is coupled directly to the microwave cavity.

  14. Laser light scattering instrument advanced technology development

    NASA Technical Reports Server (NTRS)

    Wallace, J. F.

    1993-01-01

    The objective of this advanced technology development (ATD) project has been to provide sturdy, miniaturized laser light scattering (LLS) instrumentation for use in microgravity experiments. To do this, we assessed user requirements, explored the capabilities of existing and prospective laser light scattering hardware, and both coordinated and participated in the hardware and software advances needed for a flight hardware instrument. We have successfully breadboarded and evaluated an engineering version of a single-angle glove-box instrument which uses solid state detectors and lasers, along with fiber optics, for beam delivery and detection. Additionally, we have provided the specifications and written verification procedures necessary for procuring a miniature multi-angle LLS instrument which will be used by the flight hardware project which resulted from this work and from this project's interaction with the laser light scattering community.

  15. The Linac Coherent Light Source (LCLS)*

    NASA Astrophysics Data System (ADS)

    Winick, Herman

    2002-04-01

    Advances in technology make it possible to use the SLAC linac to drive the LCLS (1), a coherent x-ray source which will deliver sub-picosecond pulses at wavelengths down to 1.5 Angstroms with an instantaneous (peak) power up to 10 GW, corresponding to a brightness 10 orders of magnitude greater than x-ray beams from the most advanced synchrotron light sources. The LCLS operates on the principle of Self-Amplified Spontaneous Emission-SASE (2); i.e., coherent emission is achieved without an optical cavity by inducing a bunch-density modulation at the scale of the optical wavelength in a single pass of a high peak current, low emittance, 15 GeV electron beam through a 100m undulator. The LCLS, and a similar project planned at DESY in Hamburg, exploit recent technological developments; high-brightness rf photocathode electron guns, emittance preservation during acceleration and compression, precision undulator magnets, and high power x-ray optics. The unique properties of LCLS radiation enable new scientific opportunities in femtochemistry, nanoscale dynamics in condensed matter, atomic physics, biological imaging, plasma physics, and warm condensed matter. A collaboration including 4 US national labs (Argonne, Brookhaven, Lawrence Livermore, and Los Alamos) along with SLAC and UCLA is conducting r&d aiming for an LCLS construction start in 2004. 1. P.Emma; Proc. Part. Accel. Conf.(PAC2001); June 18-22, 2001. 2. R.Bonifacio, C.Pellegrini, L.Narducci; Optics Comm. 50,373(1984) *Supported by the Office of Basic Energy Sciences, US Dept. of Energy.

  16. Compact X-ray Light Source Workshop Report

    SciTech Connect

    Thevuthasan, Suntharampillai; Evans, James E.; Terminello, Louis J.; Koppenaal, David W.; Manke, Kristin L.; Plata, Charity

    2012-12-01

    This report, produced jointly by EMSL and FCSD, is the result of a workshop held in September 2011 that examined the utility of a compact x-ray light source (CXLS) in addressing many scientific challenges critical to advancing energy science and technology.

  17. Comparative Study of Light Sources for Household

    NASA Astrophysics Data System (ADS)

    Pawlak, Andrzej; Zalesińska, Małgorzata

    2017-03-01

    The article describes test results that provided the ground to define and evaluate basic photometric, colorimetric and electric parameters of selected, widely available light sources, which are equivalent to a traditional incandescent 60-Watt light bulb. Overall, one halogen light bulb, three compact fluorescent lamps and eleven LED light sources were tested. In general, it was concluded that in most cases (branded products, in particular) the measured and calculated parameters differ from the values declared by manufacturers only to a small degree. LED sources prove to be the most beneficial substitute for traditional light bulbs, considering both their operational parameters and their price, which is comparable with the price of compact fluorescent lamps or, in some instances, even lower.

  18. National Synchrotron Light Source annual report 1988

    SciTech Connect

    Hulbert, S.; Lazarz, N.; Williams, G.

    1988-01-01

    This report discusses the experiment done at the National Synchrotron Light Source. Most experiments discussed involves the use of the x-ray beams to study physical properties of solid materials. (LSP)

  19. Red Shifts with Obliquely Approaching Light Sources.

    ERIC Educational Resources Information Center

    Head, C. E.; Moore-Head, M. E.

    1988-01-01

    Refutes the Doppler effect as the explanation of large red shifts in the spectra of distant galaxies and explains the relativistic effects in which the light sources approach the observer obliquely. Provides several diagrams and graphs. (YP)

  20. Microwave generated plasma light source apparatus

    SciTech Connect

    Yoshizawa, K.; Ito, H.; Kodama, H.; Komura, H.; Minowa, Y.

    1985-02-05

    A microwave generated plasma light source including a microwave generator, a microwave cavity having a light reflecting member forming at least a portion of the cavity, and a member transparent to light and opaque to microwaves disposed across an opening of the cavity opposite the feeding opening through which the microwave generator is coupled. An electrodeless discharge bulb is disposed at a position in the cavity such that the cavity operates as a resonant cavity at least when the bulb is emitting light. In the bulb is encapsulated at least one discharge light emissive substance. The bulb has a shape and is sufficiently small that the bulb acts substantially as a point light source.

  1. EDITORIAL: Special Issue on Light Sources

    NASA Astrophysics Data System (ADS)

    Wharmby, D. O.

    2008-07-01

    The papers in this Special Issue of Journal of Physics D: Applied Physics originate from the 11th International Symposium on the Science and Technology of Light Sources (LS:11) held at Fudan University, Shanghai, China, during 20 24 May 2007. Abstracts of all papers were published in the conference book Light Sources 2007 (Sheffield: FAST-LS) edited by Muqing Liu and R Devonshire. Special issues were produced after LS:9 and LS:10 and have proved to be well-cited and important sources of information for this community. The Symposia occur at three-year intervals. In this one over 200 papers were presented—the majority as posters—with ample time provided for active discussion. As all submitted papers had to be refereed in the normal way for J. Phys. D: Appl. Phys., I was concerned that too many submissions would overwhelm the small number of referees available in this area. To ensure a broad spread of interests and opinions, I invited 10 senior colleagues to give me their recommendations about who should be asked to submit papers for this Special Issue. The criteria were that the work should be new, complete and within the scope of the journal. As a result of their suggestions 42 authors were asked to submit papers. Not all authors were able to submit a manuscript in time and some, at my request, combined their work into a single paper. The 28 papers published here are the result of that process. The issue starts with a comprehensive review by Benilov of the remarkable progress that has been made in the past 15 years in understanding the behaviour of cathode and anode terminations in arcs. It is fair to say that we now have a fundamental understanding of the formerly baffling behaviour of spot and diffuse terminations, at least in the quasi-steady state. A number of following papers cover applications of this theory, extensions to time dependence and examination of the effects of the different gaseous atmospheres in which lighting arcs operate. Mercury has very

  2. Preliminary results from an advanced lighting controlstestbed

    SciTech Connect

    Avery, Douglas; Jennings, Judity; Rubinstein, Francis

    1998-03-01

    Preliminary results from a large-scale testbed of advanced lighting control technologies at the Phillip Burton Federal Building at 450 Golden Gate Ave. in San Francisco are presented. The first year objective of this project is to determine the sustainable energy savings and cost-effectiveness of different lighting control technologies compared to a portion of the building where only minimal controls are installed. The paper presents the analyzed results from six months of tests focused on accurately characterizing the energy savings potential of one type of daylight-linked lighting controls compared to the lighting in similar open-planned areas without dimming controls. After analyzing a half year;s data, we determined that the annual energy savings for this type of daylight- linked controls was 41% and 30% for the outer rows of lights on the South and North sides of the building, respectively. The annual energy savings dropped to 22% and 16% for the second row of lights for the South and North, respectively, and was negligible for the third rows of lights.

  3. Application of Light Sources to Medical Field

    NASA Astrophysics Data System (ADS)

    Mizojiri, Takafumi; Kimura, Makoto

    The purpose of this paper is to show application of light sources to medical field. It is described the process of light sources development applied to photodynamic therapy; PDT or photodynamic diagnosis; PDD. Actually, as a successful experience, we show the verification results obtained by primary and clinical experiments using metal halide lamp which emitted spectra is optimized to absorbed wavelength of photosensitizer for PDT.

  4. Superresolving multiphoton interferences with independent light sources.

    PubMed

    Oppel, S; Büttner, T; Kok, P; von Zanthier, J

    2012-12-07

    We propose to use multiphoton interferences from statistically independent light sources in combination with linear optical detection techniques to enhance the resolution in imaging. Experimental results with up to five independent thermal light sources confirm this approach to improve the spatial resolution. Since no involved quantum state preparation or detection is required, the experiment can be considered an extension of the Hanbury Brown-Twiss experiment for spatial intensity correlations of order N>2.

  5. Bright diode laser light source.

    PubMed

    Lassila, Erkki; Hernberg, Rolf

    2006-05-20

    A simplified multiwavelength prototype of an axially symmetric diode laser device based on stacks made of single emitters has been made, and the performance of the device has been demonstrated experimentally. The results verify that kilowatt-level light power can be focused into a circular spot with a 1/e2 diameter of 360 microm, a focal length of 100 mm, and a numerical aperture of 0.24, thus producing an average power density in excess of 10 kW/mm2 and a brightness of 6x10(10) W m-2 sr-1. The experiments also predict that it will be possible to increase these values to more than 60 kW/mm2 and 3x10(11) W m-2 sr-1.

  6. Advanced Photon Source Upgrade Project - Materials

    ScienceCinema

    Gibbson, Murray

    2016-07-12

    An upgrade to Advanced Photon Source announced by DOE - http://go.usa.gov/ivZ -- will help scientists break through bottlenecks in materials design in order to develop materials with desirable functions.

  7. Advances in Light Microscopy for Neuroscience

    PubMed Central

    Wilt, Brian A.; Burns, Laurie D.; Ho, Eric Tatt Wei; Ghosh, Kunal K.; Mukamel, Eran A.

    2010-01-01

    Since the work of Golgi and Cajal, light microscopy has remained a key tool for neuroscientists to observe cellular properties. Ongoing advances have enabled new experimental capabilities using light to inspect the nervous system across multiple spatial scales, including ultrastructural scales finer than the optical diffraction limit. Other progress permits functional imaging at faster speeds, at greater depths in brain tissue, and over larger tissue volumes than previously possible. Portable, miniaturized fluorescence microscopes now allow brain imaging in freely behaving mice. Complementary progress on animal preparations has enabled imaging in head-restrained behaving animals, as well as time-lapse microscopy studies in the brains of live subjects. Mouse genetic approaches permit mosaic and inducible fluorescence-labeling strategies, whereas intrinsic contrast mechanisms allow in vivo imaging of animals and humans without use of exogenous markers. This review surveys such advances and highlights emerging capabilities of particular interest to neuroscientists. PMID:19555292

  8. Advances in light microscopy for neuroscience.

    PubMed

    Wilt, Brian A; Burns, Laurie D; Wei Ho, Eric Tatt; Ghosh, Kunal K; Mukamel, Eran A; Schnitzer, Mark J

    2009-01-01

    Since the work of Golgi and Cajal, light microscopy has remained a key tool for neuroscientists to observe cellular properties. Ongoing advances have enabled new experimental capabilities using light to inspect the nervous system across multiple spatial scales, including ultrastructural scales finer than the optical diffraction limit. Other progress permits functional imaging at faster speeds, at greater depths in brain tissue, and over larger tissue volumes than previously possible. Portable, miniaturized fluorescence microscopes now allow brain imaging in freely behaving mice. Complementary progress on animal preparations has enabled imaging in head-restrained behaving animals, as well as time-lapse microscopy studies in the brains of live subjects. Mouse genetic approaches permit mosaic and inducible fluorescence-labeling strategies, whereas intrinsic contrast mechanisms allow in vivo imaging of animals and humans without use of exogenous markers. This review surveys such advances and highlights emerging capabilities of particular interest to neuroscientists.

  9. Microelectromechanical Systems (MEMS) Broadband Light Source Developed

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret L.

    2003-01-01

    A miniature, low-power broadband light source has been developed for aerospace applications, including calibrating spectrometers and powering miniature optical sensors. The initial motivation for this research was based on flight tests of a Fabry-Perot fiberoptic temperature sensor system used to detect aircraft engine exhaust gas temperature. Although the feasibility of the sensor system was proven, the commercial light source optically powering the device was identified as a critical component requiring improvement. Problems with the light source included a long stabilization time (approximately 1 hr), a large amount of heat generation, and a large input electrical power (6.5 W). Thus, we developed a new light source to enable the use of broadband optical sensors in aerospace applications. Semiconductor chip-based light sources, such as lasers and light-emitting diodes, have a relatively narrow range of emission wavelengths in comparison to incandescent sources. Incandescent light sources emit broadband radiation from visible to infrared wavelengths; the intensity at each wavelength is determined by the filament temperature and the materials chosen for the filament and the lamp window. However, present commercial incandescent light sources are large in size and inefficient, requiring several watts of electrical power to obtain the desired optical power, and they emit a large percentage of the input power as heat that must be dissipated. The miniature light source, developed jointly by the NASA Glenn Research Center, the Jet Propulsion Laboratory, and the Lighting Innovations Institute, requires one-fifth the electrical input power of some commercial light sources, while providing similar output light power that is easily coupled to an optical fiber. Furthermore, it is small, rugged, and lightweight. Microfabrication technology was used to reduce the size, weight, power consumption, and potential cost-parameters critical to future aerospace applications. This chip

  10. Light emitting diodes as a plant lighting source

    NASA Technical Reports Server (NTRS)

    Bula, R. J.; Tennessen, D. J.; Morrow, R. C.; Tibbitts, T. W.

    1994-01-01

    Electroluminescence in solid materials is defined as the generation of light by the passage of an electric current through a body of solid material under an applied electric field. A specific type of electroluminescence, first noted in 1923, involves the generation of photons when electrons are passed through a p-n junction of certain solid materials (junction of a n-type semiconductor, an electron donor, and a p-type semiconductor, an electron acceptor). The development of this light emitting semiconductor technology dates back less than 30 years. During this period of time, the LED has evolved from a rare and expensive light generating device to one of the most widely used electronic components. A number of LED characteristics are of considerable importance in selecting a light source for plant lighting in a controlled environment facility. Of particular importance is the characteristic that light is generated by an LED at a rate far greater than the corresponding thermal radiation predicted by the bulk temperature of the device as defined by Plank's radiation law. This is in sharp contrast to other light sources, such as an incandescent or high intensity discharge lamp. A plant lighting system for controlled environments must provide plants with an adequate flux of photosynthetically active radiation, plus providing photons in the spectral regions that are involved in the photomorphogenic and phototropic responses that result in normal plant growth and development. Use of light sources that emit photons over a broad spectral range generally meet these two lighting requirements. Since the LED's emit over specific spectral regions, they must be carefully selected so that the levels of photsynthetically active and photomorphogenic and phototropic radiation meet these plant requirements.

  11. Proposals for synchrotron light sources

    SciTech Connect

    Teng, L.C.

    1985-06-01

    Ever since it was first applied in the 1960's synchrotron radiation from an accelerating electron beam has been gaining popularity as a powerful tool for research and development in a wide variety of fields of science and technology. By now there are some 20 facilities operating either parasitically or dedicatedly for synchrotron radiation research in different parts of the world. In addition there are another 20 facilities either in construction or in various stages of proposal and design. The experiences gained from the operating facilities and the recent development of insertion devices such as wigglers and undulators as radiation sources led to a new set of requirements on the design of synchrotron radiation storage rings for optimum utility. The surprisingly uniform applicability and unanimous acceptance of these criteria give assurance that they are indeed valid criteria derived form mature considerations and experiences. Instead of describing the design of each of these new facilities it is, thus, more effective to discuss these desirable design features and indicate how they are incorporated in the design using machines listed as examples. 9 refs., 7 figs., 2 tabs.

  12. Squeezed light for advanced gravitational wave detectors and beyond.

    PubMed

    Oelker, E; Barsotti, L; Dwyer, S; Sigg, D; Mavalvala, N

    2014-08-25

    Recent experiments have demonstrated that squeezed vacuum states can be injected into gravitational wave detectors to improve their sensitivity at detection frequencies where they are quantum noise limited. Squeezed states could be employed in the next generation of more sensitive advanced detectors currently under construction, such as Advanced LIGO, to further push the limits of the observable gravitational wave Universe. To maximize the benefit from squeezing, environmentally induced disturbances such as back scattering and angular jitter need to be mitigated. We discuss the limitations of current squeezed vacuum sources in relation to the requirements imposed by future gravitational wave detectors, and show a design for squeezed light injection which overcomes these limitations.

  13. High-intensity sources for light ions

    SciTech Connect

    Leung, K.N.

    1995-10-01

    The use of the multicusp plasma generator as a source of light ions is described. By employing radio-frequency induction discharge, the performance of the multicusp source is greatly improved, both in lifetime and in high brightness H{sup +} and H{sup {minus}} beam production. A new technique for generating multiply-charged ions in this type of ion source is also presented.

  14. Recent Advances of Light-Mediated Theranostics

    PubMed Central

    Ai, Xiangzhao; Mu, Jing; Xing, Bengang

    2016-01-01

    -triggered theranostic strategies and introduced their great advances in biomedical applications in recent years. Moreover, some other promising light-assisted techniques, such as photoacoustic and Cerenkov radiation, were also systemically discussed. Finally, the potential challenges and future perspectives for light-mediated deep-tissue diagnosis and therapeutics were proposed. PMID:27877246

  15. Advanced Neutron Source (ANS) Project progress report

    SciTech Connect

    McBee, M.R.; Chance, C.M. ); Selby, D.L.; Harrington, R.M.; Peretz, F.J. )

    1990-04-01

    This report discusses the following topics on the advanced neutron source: quality assurance (QA) program; reactor core development; fuel element specification; corrosion loop tests and analyses; thermal-hydraulic loop tests; reactor control concepts; critical and subcritical experiments; material data, structural tests, and analysis; cold source development; beam tube, guide, and instrument development; hot source development; neutron transport and shielding; I C research and development; facility concepts; design; and safety.

  16. Electrodeless lighting RF power source development. Final report

    SciTech Connect

    1996-08-30

    An efficient, solid state RF power source has been developed on this NICE project for exciting low power electrodeless lamp bulbs. This project takes full advantage of concurrent advances in electrodeless lamp technology. Electrodeless lamp lighting systems utilizing the sulfur based bulb type developed by Fusion Lighting, Inc., is an emerging technology which is based on generating light in a confined plasma created and sustained by RF excitation. The bulb for such a lamp is filled with a particular element and inert gas at low pressure when cold. RF power from the RF source creates a plasma within the bulb which reaches temperatures approaching those of high pressure discharge lamp plasmas. At these temperatures the plasma radiates substantial visible light with a spectrum similar to sunlight.

  17. Increased collection efficiency of LIFI high intensity electrodeless light source

    NASA Astrophysics Data System (ADS)

    Hafidi, Abdeslam; DeVincentis, Marc; Duelli, Markus; Gilliard, Richard

    2008-02-01

    Recently, RF driven electrodeless high intensity light sources have been implemented successfully in the projection display systems for HDTV and videowall applications. This paper presents advances made in the RF waveguide and electric field concentrator structures with the purpose of reducing effective arc size and increasing light collection. In addition, new optical designs are described that further improve system efficiency. The results of this work demonstrate that projection system light throughput is increased relative to previous implementations and performance is optimized for home theater and other front projector applications that maintain multi-year lifetime without re-lamping, complete spectral range, fast start times and high levels of dynamic contrast due to dimming flexibility in the light source system.

  18. Light sources based on semiconductor current filaments

    DOEpatents

    Zutavern, Fred J.; Loubriel, Guillermo M.; Buttram, Malcolm T.; Mar, Alan; Helgeson, Wesley D.; O'Malley, Martin W.; Hjalmarson, Harold P.; Baca, Albert G.; Chow, Weng W.; Vawter, G. Allen

    2003-01-01

    The present invention provides a new type of semiconductor light source that can produce a high peak power output and is not injection, e-beam, or optically pumped. The present invention is capable of producing high quality coherent or incoherent optical emission. The present invention is based on current filaments, unlike conventional semiconductor lasers that are based on p-n junctions. The present invention provides a light source formed by an electron-hole plasma inside a current filament. The electron-hole plasma can be several hundred microns in diameter and several centimeters long. A current filament can be initiated optically or with an e-beam, but can be pumped electrically across a large insulating region. A current filament can be produced in high gain photoconductive semiconductor switches. The light source provided by the present invention has a potentially large volume and therefore a potentially large energy per pulse or peak power available from a single (coherent) semiconductor laser. Like other semiconductor lasers, these light sources will emit radiation at the wavelength near the bandgap energy (for GaAs 875 nm or near infra red). Immediate potential applications of the present invention include high energy, short pulse, compact, low cost lasers and other incoherent light sources.

  19. Research on Modern Gas Discharge Light Sources

    NASA Astrophysics Data System (ADS)

    Born, M.; Markus, T.

    This article gives an overview of today's gas discharge light sources and their application fields with focus on research aspects. In Sect. 15.1 of this chapter, an introduction to electric light sources, the lighting market and related research topics is outlined. Due to the complexity of the subject, we have focused on selected topics in the field of high intensity discharge (HID) lamps since these represent an essential part of modern lamp research. The working principle and light technical properties of HID lamps are described in Sect. 15.2. Physical and thermochemical modelling procedures and tools as well as experimental analysis are discussed in Sects. 15.3 and 15.4, respectively. These tools result in a detailed scientific insight into the complexity of real discharge lamps. In particular, analysis and modelling are the keys for further improvement and development of existing and new products.

  20. Infrared light sources with semimetal electron injection

    DOEpatents

    Kurtz, Steven R.; Biefeld, Robert M.; Allerman, Andrew A.

    1999-01-01

    An infrared light source is disclosed that comprises a layered semiconductor active region having a semimetal region and at least one quantum-well layer. The semimetal region, formed at an interface between a GaAsSb or GalnSb layer and an InAsSb layer, provides electrons and holes to the quantum-well layer to generate infrared light at a predetermined wavelength in the range of 2-6 .mu.m. Embodiments of the invention can be formed as electrically-activated light-emitting diodes (LEDs) or lasers, and as optically-pumped lasers. Since the active region is unipolar, multiple active regions can be stacked to form a broadband or multiple-wavelength infrared light source.

  1. Robust photometric stereo using structural light sources

    NASA Astrophysics Data System (ADS)

    Han, Tian-Qi; Cheng, Yue; Shen, Hui-Liang; Du, Xin

    2014-05-01

    We propose a robust photometric stereo method by using structural arrangement of light sources. In the arrangement, light sources are positioned on a planar grid and form a set of collinear combinations. The shadow pixels are detected by adaptive thresholding. The specular highlight and diffuse pixels are distinguished according to their intensity deviations of the collinear combinations, thanks to the special arrangement of light sources. The highlight detection problem is cast as a pattern classification problem and is solved using support vector machine classifiers. Considering the possible misclassification of highlight pixels, the ℓ1 regularization is further employed in normal map estimation. Experimental results on both synthetic and real-world scenes verify that the proposed method can robustly recover the surface normal maps in the case of heavy specular reflection and outperforms the state-of-the-art techniques.

  2. Plasmas as Light Sources for Lasers.

    DTIC Science & Technology

    1984-09-01

    RD-R159 460 PLASMS RS LIGHT SOURCES FOR LSERS(U) LBANA UNIV IN ./I HUNTSVILLE T A BARR ET AL. SEP 64 ANSMI/RH-CR-85-14 pAAHS-82-D-AS±6 N...and experimental results are presented, together with a * possible explanation of the optical radiation-tim history of the plasm . Potential...into a cold pl’sma device at Te - 1 eV and l018 / cc ions. Incidentally this experiment showed why there may be a need for a plasma light source

  3. Design calculations for the ANS (Advanced Neutron Source) cold source

    SciTech Connect

    Lillie, R.A.; Alsmiller, R.G. Jr.

    1988-01-01

    The calculation procedure, based on discrete ordinates transport methods, that is being used to carry out design calculations for the Advanced Neutron Source cold source is described. Calculated results on the gain in cold neutron flux produced by a liquid deuterium cold source are compared with experimental data and with calculated data previously obtained by P. Ageron et al., at the Institute Max von Laue-Paul Langevin in Grenoble, France. Calculated results are also presented that indicated how the flux of cold neutrons vary with cold source parameters. 23 refs., 5 figs., 3 tabs.

  4. Circular dichroism beamline B23 at the Diamond Light Source.

    PubMed

    Hussain, Rohanah; Jávorfi, Tamás; Siligardi, Giuliano

    2012-01-01

    Synchrotron radiation circular dichroism (SRCD) is a well established technique in structural biology. The first UV-VIS beamline, dedicated to circular dichroism, at Diamond Light Source Ltd, a third-generation synchrotron facility in south Oxfordshire, UK, has recently become operational and it is now available for the user community. Herein the main characteristics of the B23 SRCD beamline, the ancillary facilities available for users, and some of the recent advances achieved are summarized.

  5. Tunable pulsed narrow bandwidth light source

    DOEpatents

    Powers, Peter E.; Kulp, Thomas J.

    2002-01-01

    A tunable pulsed narrow bandwidth light source and a method of operating a light source are provided. The light source includes a pump laser, first and second non-linear optical crystals, a tunable filter, and light pulse directing optics. The method includes the steps of operating the pump laser to generate a pulsed pump beam characterized by a nanosecond pulse duration and arranging the light pulse directing optics so as to (i) split the pulsed pump beam into primary and secondary pump beams; (ii) direct the primary pump beam through an input face of the first non-linear optical crystal such that a primary output beam exits from an output face of the first non-linear optical crystal; (iii) direct the primary output beam through the tunable filter to generate a sculpted seed beam; and direct the sculpted seed beam and the secondary pump beam through an input face of the second non-linear optical crystal such that a secondary output beam characterized by at least one spectral bandwidth on the order of about 0.1 cm.sup.-1 and below exits from an output face of the second non-linear optical crystal.

  6. National Synchrotron Light Source 2010 Activity Report

    SciTech Connect

    Rowe, M.; Snyder, K. J.

    2010-12-29

    This is a very exciting period for photon sciences at Brookhaven National Laboratory. It is also a time of unprecedented growth for the Photon Sciences Directorate, which operates the National Synchrotron Light Source (NSLS) and is constructing NSLS-II, both funded by the Department of Energy's Office of Science. Reflecting the quick pace of our activities, we chose the theme 'Discovery at Light Speed' for the directorate's 2010 annual report, a fiscal year bookended by October 2009 and September 2010. The year began with the news that NSLS users Venki Ramakrishnan of Cambridge University (also a former employee in Brookhaven's biology department) and Thomas A. Steitz of Yale University were sharing the 2009 Nobel Prize in Chemistry with Ada E. Yonath of the Weizmann Institute of Science. Every research project has the potential for accolades. In 2010, NSLS users and staff published close to 900 papers, with about 170 appearing in premiere journals. Those are impressive stats for a facility nearly three decades old, testament to the highly dedicated team keeping NSLS at peak performance and the high quality of its user community. Our NSLS users come from a worldwide community of scientists using photons, or light, to carry out research in energy and environmental sciences, physics, materials science, chemistry, biology and medicine. All are looking forward to the new capabilities enabled by NSLS-II, which will offer unprecedented resolution at the nanoscale. The new facility will produce x-rays more than 10,000 times brighter than the current NSLS and host a suite of sophisticated instruments for cutting-edge science. Some of the scientific discoveries we anticipate at NSLS-II will lead to major advances in alternative energy technologies, such as hydrogen and solar. These discoveries could pave the way to: (1) catalysts that split water with sunlight for hydrogen production; (2) materials that can reversibly store large quantities of electricity or hydrogen; (3

  7. The Advanced Photon Source looks to the future.

    SciTech Connect

    Fenner, R. B; Gerig, R. E.; Gibson, J. M.; Gluskin, E.; Long, G. G.; Mills, D. M.; Ruzicka, W. G.

    2007-11-11

    The Advanced Photon Source (APS) at Argonne National Laboratory is in its 12th year since producing first light. With an eye on the next 10 years, facility management have developed plans that address priorities for new and/or improved beamlines over the next 5-10 years with a strong evolution toward a greater number of dedicated beamlines. In addition, options, including an energy-recovery linac, are being evaluated for a planned upgrade of the APS.

  8. Mobile-phone based visible light communication using region-grow light source tracking for unstable light source.

    PubMed

    Liang, Kevin; Chow, Chi-Wai; Liu, Yang

    2016-07-25

    In order to increase the data rate of the camera-based visible light communication (VLC) system, using rolling shutter effect has been demonstrated successfully, in which the pixel rows of the complementary-metal-oxide-semiconductor (CMOS) image sensor are activated sequentially. Previous camera-based VLCs focused on using a stable LED light source, and its illumination area is positioned at the center of an image frame. In this work, we investigate the performance of a camera-based VLC with light source at different parts of an image frame. We propose and demonstrate using region-grow algorithm to track the light source. We also evaluate and discuss different scenarios when the light source is moved. Besides, a recorded > 5 kbit/s net data rate can be achieved by using only a single phosphor-based white-light LED source. Here, we demonstrate that 4.502 pixel/bit can be achieved.

  9. IR beamline at the Swiss Light Source

    NASA Astrophysics Data System (ADS)

    Ph, Lerch; L, Quaroni; J, Wambach; J, Schneider; B, Armstrong D.; D, Rossetti; L, Mueller F.; P, Peier; V, Schlott; L, Carroll; P, Friedli; H, Sigg; S, Stutz; M, Tran

    2012-05-01

    The infrared beamline at the Swiss light source uses dipole radiation and is designed to transport light to four experimental stations, A, B, C, D. Branch A is dedicated to far IR work in vacuum; branch B is a micro-spectrometer; branch C is dedicated to high resolution spectroscopy in the gas phase; branch D is a pump and probe set-up. This contribution describes the optical layout and provides a brief survey of currently available experimental stations. The beamline is in regular user operation since 2009.

  10. Rf capacitively-coupled electrodeless light source

    DOEpatents

    Manos, Dennis M.; Diggs, Jessie; Ametepe, Joseph D.; Fugitt, Jock A.

    2000-01-01

    An rf capacitively-coupled electrodeless light source is provided. The light source comprises a hollow, elongated chamber and at least one center conductor disposed within the hollow, elongated chamber. A portion of each center conductor extends beyond the hollow, elongated chamber. At least one gas capable of forming an electronically excited molecular state is contained within each center conductor. An electrical coupler is positioned concentric to the hollow, elongated chamber and the electrical coupler surrounds the portion of each center conductor that extends beyond the hollow, elongated chamber. A rf-power supply is positioned in an operable relationship to the electrical coupler and an impedance matching network is positioned in an operable relationship to the rf power supply and the electrical coupler.

  11. Backscatter absorption gas imaging systems and light sources therefore

    DOEpatents

    Kulp, Thomas Jan; Kliner, Dahv A. V.; Sommers, Ricky; Goers, Uta-Barbara; Armstrong, Karla M.

    2006-12-19

    The location of gases that are not visible to the unaided human eye can be determined using tuned light sources that spectroscopically probe the gases and cameras that can provide images corresponding to the absorption of the gases. The present invention is a light source for a backscatter absorption gas imaging (BAGI) system, and a light source incorporating the light source, that can be used to remotely detect and produce images of "invisible" gases. The inventive light source has a light producing element, an optical amplifier, and an optical parametric oscillator to generate wavelength tunable light in the IR. By using a multi-mode light source and an amplifier that operates using 915 nm pump sources, the power consumption of the light source is reduced to a level that can be operated by batteries for long periods of time. In addition, the light source is tunable over the absorption bands of many hydrocarbons, making it useful for detecting hazardous gases.

  12. Science and Technology of Future Light Sources

    SciTech Connect

    Dierker,S.; Bergmann, U.; Corlett, J.; Dierker, S.; Falcone, R.; Galayda, J.; Gibson, M.; Hastings, J.; Hettel, B.; Hill, J.; Hussain, Z.; Kao, C.-C.; Kirx, J.; Long, G.; McCurdy, B.; Raubenheimer, T.; Sannibale, F.; Seeman, J.; Shen, Z.-X.; Shenoy, g.; Schoenlein, B.; Shen, Q.; Stephenson, B.; Stohr, J.; Zholents, A.

    2008-12-01

    Many of the important challenges facing humanity, including developing alternative sources of energy and improving health, are being addressed by advances that demand the improved understanding and control of matter. While the visualization, exploration, and manipulation of macroscopic matter have long been technological goals, scientific developments in the twentieth century have focused attention on understanding matter on the atomic scale through the underlying framework of quantum mechanics. Of special interest is matter that consists of natural or artificial nanoscale building blocks defined either by atomic structural arrangements or by electron or spin formations created by collective correlation effects. The essence of the challenge to the scientific community has been expressed in five grand challenges for directing matter and energy recently formulated by the Basic Energy Sciences Advisory Committee [1]. These challenges focus on increasing our understanding of, and ultimately control of, matter at the level of atoms, electrons. and spins, as illustrated in Figure 1.1, and serve the entire range of science from advanced materials to life sciences. Meeting these challenges will require new tools that extend our reach into regions of higher spatial, temporal, and energy resolution. X-rays with energies above 10 keV offer capabilities extending beyond the nanoworld shown in Figure 1.1 due to their ability to penetrate into optically opaque or thick objects. This opens the door to combining atomic level information from scattering studies with 3D information on longer length scales from real space imaging with a resolution approaching 1 nm. The investigation of multiple length scales is important in hierarchical structures, providing knowledge about function of living organisms, the atomistic origin of materials failure, the optimization of industrial synthesis, or the working of devices. Since the fundamental interaction that holds matter together is of

  13. Science and Technology of Future Light Sources

    SciTech Connect

    Bergmann, Uwe; Corlett, John; Dierker, Steve; Falcone, Roger; Galayda, John; Gibson, Murray; Hastings, Jerry; Hettel, Bob; Hill, John; Hussain, Zahid; Kao, Chi-Chang; Kirz, Janos; Long, Danielle; McCurdy, Bill; Raubenheimer, Tor; Sannibale, Fernando; Seeman, John; Shen, Z. -X.; Schenoy, Gopal; Schoenlein, Bob; Shen, Qun; Stephenson, Brian; Stohr, Joachim; Zholents, Alexander

    2009-01-28

    Many of the important challenges facing humanity, including developing alternative sources of energy and improving health, are being addressed by advances that demand the improved understanding and control of matter. While the visualization, exploration, and manipulation of macroscopic matter have long been technological goals, scientific developments in the twentieth century have focused attention on understanding matter on the atomic scale through the underlying framework of quantum mechanics. Of special interest is matter that consists of natural or artificial nanoscale building blocks defined either by atomic structural arrangements or by electron or spin formations created by collective correlation effects The essence of the challenge to the scientific community has been expressed in five grand challenges for directing matter and energy recently formulated by the Basic Energy Sciences Advisory Committee. These challenges focus on increasing our understanding of, and ultimately control of, matter at the level of atoms, electrons. and spins, as illustrated in Figure 1.1, and serve the entire range of science from advanced materials to life sciences. Meeting these challenges will require new tools that extend our reach into regions of higher spatial, temporal, and energy resolution. X-rays with energies above 10 keV offer capabilities extending beyond the nanoworld shown in Figure 1.1 due to their ability to penetrate into optically opaque or thick objects. This opens the door to combining atomic level information from scattering studies with 3D information on longer length scales from real space imaging with a resolution approaching 1 nm. The investigation of multiple length scales is important in hierarchical structures, providing knowledge about function of living organisms, the atomistic origin of materials failure, the optimization of industrial synthesis, or the working of devices. Since the fundamental interaction that holds matter together is of

  14. Brain protein deciphered at Advanced Light Source

    SciTech Connect

    2010-01-01

    This computer-generated model of a rat glutamate receptor is the first complete portrait of this important link in the nervous system. At the top of the Y-shaped protein, a pair of molecules splay outward like diverging prongs. The bottom section, which is embedded in a neuronal membrane, houses the ion channel. The resolution of this image is 3.6 angstroms per pixel, or just under four ten-billionths of a meter per image unit. http://newscenter.lbl.gov/feature-stories/2010/01/21/glutamate-receptor/

  15. Advanced light source. Activity report 1995

    SciTech Connect

    1996-07-01

    The ALS Activity Report is designed to share the breadth, variety, and interest of the scientific program and ongoing R&D efforts in a form that is accessible to a broad audience. Recent research results are presented in six sections, each representing an important theme in ALS science. These results are designed to demonstrate the capabilities of the ALS, rather than to give a comprehensive review of 1995 experiments. Although the scientific program and facilities report are separate sections, in practice the achievements and accomplishments of users and ALS staff are interdependent. This user-staff collaboration is essential to help us direct our efforts toward meeting the needs of the user community, and to ensure the continued success of the ALS as a premier facility.

  16. Advanced Neutron Source: The users' perspective

    SciTech Connect

    Peretz, F.J.

    1990-01-01

    User experiments will cover fields such as activation analysis of pollutants, irradiation of materials for the fusion program, and neutron scattering studies of materials as diverse as viruses, aerospace composites, and superconductors. Production capabilities must also be provided for the production of isotopes, especially of transuranic elements. The different ways in which these research areas and their required infrastructure influence the design of the Advanced Neutron Source will be the subject of this paper.

  17. Insertion devices at the advanced photon source

    SciTech Connect

    Moog, E.R.

    1996-07-01

    The insertion devices being installed at the Advanced Photon Source cause the stored particle beam to wiggle, emitting x-rays with each wiggle. These x-rays combine to make an intense beam of radiation. Both wiggler and undulator types of insertion devices are being installed; the characteristics of the radiation produced by these two types of insertion devices are discussed, along with the reasons for those characteristics.

  18. Cathode R&D for Future Light Sources

    SciTech Connect

    Dowell, D.H.; Bazarov, I.; Dunham, B.; Harkay, K.; Hernandez-Garcia; Legg, R.; Padmore, H.; Rao, T.; Smedley, J.; Wan, W.; /LBL, Berkeley

    2010-05-26

    This paper reviews the requirements and current status of cathodes for accelerator applications, and proposes a research and development plan for advancing cathode technology. Accelerator cathodes need to have long operational lifetimes and produce electron beams with a very low emittance. The two principal emission processes to be considered are thermionic and photoemission with the photocathodes being further subdivided into metal and semi-conductors. Field emission cathodes are not included in this analysis. The thermal emittance is derived and the formulas used to compare the various cathode materials. To date, there is no cathode which provides all the requirements needed for the proposed future light sources. Therefore a three part research plan is described to develop cathodes for these future light source applications.

  19. The JLab high power ERL light source

    SciTech Connect

    G.R. Neil; C. Behre; S.V. Benson; M. Bevins; G. Biallas; J. Boyce; J. Coleman; L.A. Dillon-Townes; D. Douglas; H.F. Dylla; R. Evans; A. Grippo; D. Gruber; J. Gubeli; D. Hardy; C. Hernandez-Garcia; K. Jordan; M.J. Kelley; L. Merminga; J. Mammosser; W. Moore; N. Nishimori; E. Pozdeyev; J. Preble; R. Rimmer; Michelle D. Shinn; T. Siggins; C. Tennant; R. Walker; G.P. Williams and S. Zhang

    2005-03-19

    A new THz/IR/UV photon source at Jefferson Lab is the first of a new generation of light sources based on an Energy-Recovered, (superconducting) Linac (ERL). The machine has a 160 MeV electron beam and an average current of 10 mA in 75 MHz repetition rate hundred femtosecond bunches. These electron bunches pass through a magnetic chicane and therefore emit synchrotron radiation. For wavelengths longer than the electron bunch the electrons radiate coherently a broadband THz {approx} half cycle pulse whose average brightness is > 5 orders of magnitude higher than synchrotron IR sources. Previous measurements showed 20 W of average power extracted[1]. The new facility offers simultaneous synchrotron light from the visible through the FIR along with broadband THz production of 100 fs pulses with >200 W of average power. The FELs also provide record-breaking laser power [2]: up to 10 kW of average power in the IR from 1 to 14 microns in 400 fs pulses at up to 74.85 MHz repetition rates and soon will produce similar pulses of 300-1000 nm light at up to 3 kW of average power from the UV FEL. These ultrashort pulses are ideal for maximizing the interaction with material surfaces. The optical beams are Gaussian with nearly perfect beam quality. See www.jlab.org/FEL for details of the operating characteristics; a wide variety of pulse train configurations are feasible from 10 microseconds long at high repetition rates to continuous operation. The THz and IR system has been commissioned. The UV system is to follow in 2005. The light is transported to user laboratories for basic and applied research. Additional lasers synchronized to the FEL are also available. Past activities have included production of carbon nanotubes, studies of vibrational relaxation of interstitial hydrogen in silicon, pulsed laser deposition and ablation, nitriding of metals, and energy flow in proteins. This paper will present the status of the system and discuss some of the discoveries we have made

  20. The JLab high power ERL light source

    NASA Astrophysics Data System (ADS)

    Neil, G. R.; Behre, C.; Benson, S. V.; Bevins, M.; Biallas, G.; Boyce, J.; Coleman, J.; Dillon-Townes, L. A.; Douglas, D.; Dylla, H. F.; Evans, R.; Grippo, A.; Gruber, D.; Gubeli, J.; Hardy, D.; Hernandez-Garcia, C.; Jordan, K.; Kelley, M. J.; Merminga, L.; Mammosser, J.; Moore, W.; Nishimori, N.; Pozdeyev, E.; Preble, J.; Rimmer, R.; Shinn, M.; Siggins, T.; Tennant, C.; Walker, R.; Williams, G. P.; Zhang, S.

    2006-02-01

    A new THz/IR/UV photon source at Jefferson Lab is the first of a new generation of light sources based on an Energy-Recovered, (superconducting) Linac (ERL). The machine has a 160 MeV electron beam and an average current of 10 mA in 75 MHz repetition rate hundred femtosecond bunches. These electron bunches pass through a magnetic chicane and therefore emit synchrotron radiation. For wavelengths longer than the electron bunch the electrons radiate coherently a broadband THz ˜ half cycle pulse whose average brightness is >5 orders of magnitude higher than synchrotron IR sources. Previous measurements showed 20 W of average power extracted [Carr, et al., Nature 420 (2002) 153]. The new facility offers simultaneous synchrotron light from the visible through the FIR along with broadband THz production of 100 fs pulses with >200 W of average power. The FELs also provide record-breaking laser power [Neil, et al., Phys. Rev. Lett. 84 (2000) 662]: up to 10 kW of average power in the IR from 1 to 14 μm in 400 fs pulses at up to 74.85 MHz repetition rates and soon will produce similar pulses of 300-1000 nm light at up to 3 kW of average power from the UV FEL. These ultrashort pulses are ideal for maximizing the interaction with material surfaces. The optical beams are Gaussian with nearly perfect beam quality. See www.jlab.org/FEL for details of the operating characteristics; a wide variety of pulse train configurations are feasible from 10 ms long at high repetition rates to continuous operation. The THz and IR system has been commissioned. The UV system is to follow in 2005. The light is transported to user laboratories for basic and applied research. Additional lasers synchronized to the FEL are also available. Past activities have included production of carbon nanotubes, studies of vibrational relaxation of interstitial hydrogen in silicon, pulsed laser deposition and ablation, nitriding of metals, and energy flow in proteins. This paper will present the status of the

  1. Status of the advanced photon source

    SciTech Connect

    Galayda, J.

    1996-12-31

    This report presents general information on the Advanced Photon Source (APS) and then breaks down the APS project into three categories: accelerator systems, experimental facilities, and conventional facilities. The accelerator systems consist of the 7 GeV APS positron storage ring and a 7 GeV positron injector. The experimental facilities include 20 undulator radiation sources and the x-ray beamline components necessary to transport their extraordinarily intense x-ray beams outside the accelerator enclosure. Also included are x-ray beamline components for 20 bending magnet radiation sources. The conventional facilities consist of the accelerator enclosures, a 35,300 m{sup 2} experimental hall to house the x-ray beamlines, an office building for the APS staff and lab/office facilities for the research groups which will construct and operate the first 40 beamlines. APS users are described, and the properties of synchrotron radiation are discussed.

  2. Advanced interdisciplinary undergraduate program: light engineering

    NASA Astrophysics Data System (ADS)

    Bakholdin, Alexey; Bougrov, Vladislav; Voznesenskaya, Anna; Ezhova, Kseniia

    2016-09-01

    The undergraduate educational program "Light Engineering" of an advanced level of studies is focused on development of scientific learning outcomes and training of professionals, whose activities are in the interdisciplinary fields of Optical engineering and Technical physics. The program gives practical experience in transmission, reception, storage, processing and displaying information using opto-electronic devices, automation of optical systems design, computer image modeling, automated quality control and characterization of optical devices. The program is implemented in accordance with Educational standards of the ITMO University. The specific features of the Program is practice- and problem-based learning implemented by engaging students to perform research and projects, internships at the enterprises and in leading Russian and international research educational centers. The modular structure of the Program and a significant proportion of variable disciplines provide the concept of individual learning for each student. Learning outcomes of the program's graduates include theoretical knowledge and skills in natural science and core professional disciplines, deep knowledge of modern computer technologies, research expertise, design skills, optical and optoelectronic systems and devices.

  3. Holographic free-electron light source

    NASA Astrophysics Data System (ADS)

    Li, Guanhai; Clarke, Brendan P.; So, Jin-Kyu; MacDonald, Kevin F.; Zheludev, Nikolay I.

    2016-12-01

    Recent advances in the physics and technology of light generation via free-electron proximity and impact interactions with nanostructures (gratings, photonic crystals, nano-undulators, metamaterials and antenna arrays) have enabled the development of nanoscale-resolution techniques for such applications as mapping plasmons, studying nanoparticle structural transformations and characterizing luminescent materials (including time-resolved measurements). Here, we introduce a universal approach allowing generation of light with prescribed wavelength, direction, divergence and topological charge via point-excitation of holographic plasmonic metasurfaces. It is illustrated using medium-energy free-electron injection to generate highly-directional visible to near-infrared light beams, at selected wavelengths in prescribed azimuthal and polar directions, with brightness two orders of magnitude higher than that from an unstructured surface, and vortex beams with topological charge up to ten. Such emitters, with micron-scale dimensions and the freedom to fully control radiation parameters, offer novel applications in nano-spectroscopy, nano-chemistry and sensing.

  4. Holographic free-electron light source

    PubMed Central

    Li, Guanhai; Clarke, Brendan P.; So, Jin-Kyu; MacDonald, Kevin F.; Zheludev, Nikolay I.

    2016-01-01

    Recent advances in the physics and technology of light generation via free-electron proximity and impact interactions with nanostructures (gratings, photonic crystals, nano-undulators, metamaterials and antenna arrays) have enabled the development of nanoscale-resolution techniques for such applications as mapping plasmons, studying nanoparticle structural transformations and characterizing luminescent materials (including time-resolved measurements). Here, we introduce a universal approach allowing generation of light with prescribed wavelength, direction, divergence and topological charge via point-excitation of holographic plasmonic metasurfaces. It is illustrated using medium-energy free-electron injection to generate highly-directional visible to near-infrared light beams, at selected wavelengths in prescribed azimuthal and polar directions, with brightness two orders of magnitude higher than that from an unstructured surface, and vortex beams with topological charge up to ten. Such emitters, with micron-scale dimensions and the freedom to fully control radiation parameters, offer novel applications in nano-spectroscopy, nano-chemistry and sensing. PMID:27910853

  5. Plasma-based EUV light source

    DOEpatents

    Shumlak, Uri; Golingo, Raymond; Nelson, Brian A.

    2010-11-02

    Various mechanisms are provided relating to plasma-based light source that may be used for lithography as well as other applications. For example, a device is disclosed for producing extreme ultraviolet (EUV) light based on a sheared plasma flow. The device can produce a plasma pinch that can last several orders of magnitude longer than what is typically sustained in a Z-pinch, thus enabling the device to provide more power output than what has been hitherto predicted in theory or attained in practice. Such power output may be used in a lithography system for manufacturing integrated circuits, enabling the use of EUV wavelengths on the order of about 13.5 nm. Lastly, the process of manufacturing such a plasma pinch is discussed, where the process includes providing a sheared flow of plasma in order to stabilize it for long periods of time.

  6. PREFACE: Diagnostics for electrical discharge light sources: pushing the limits Diagnostics for electrical discharge light sources: pushing the limits

    NASA Astrophysics Data System (ADS)

    Zissis, Georges; Haverlag, Marco

    2010-06-01

    Light sources play an indispensable role in the daily life of any human being. Quality of life, health and urban security related to traffic and crime prevention depend on light and on its quality. In fact, every day approximately 30 billion electric light sources operate worldwide. These electric light sources consume almost 19% of worldwide electricity production. Finding new ways to light lamps is a challenge where the stakes are scientific, technological, economic and environmental. The production of more efficient light sources is a sustainable solution for humanity. There are many opportunities for not only enhancing the efficiency and reliability of lighting systems but also for improving the quality of light as seen by the end user. This is possible through intelligent use of new technologies, deep scientific understanding of the operating principles of light sources and knowledge of the varied human requirements for different types of lighting in different settings. A revolution in the domain of light source technology is on the way: high brightness light emitting diodes arriving in the general lighting market, together with organic LEDs (OLEDs), are producing spectacular advances. However, unlike incandescence, electrical discharge lamps are far from disappearing from the market. In addition, new generations of discharge lamps based on molecular radiators are becoming a reality. There are still many scientific and technological challenges to be raised in this direction. Diagnostics are important for understanding the fundamental mechanisms taking place in the discharge plasma. This understanding is an absolute necessity for system optimization leading to more efficient and high quality light sources. The studied medium is rather complex, but new diagnostic techniques coupled to innovative ideas and powerful tools have been developed in recent years. This cluster issue of seven papers illustrates these efforts. The selected papers cover all domains, from

  7. Linac Coherent Light Source Electron Beam Collimation

    SciTech Connect

    Wu, J.; Dowell, D.; Emma, P.; Limborg-Deprey, C.; Schmerge, J.F.; /SLAC

    2007-04-27

    This paper describes the design and simulation of the electron beam collimation system in the Linac Coherent Light Source (LCLS). Dark current is expected from the gun and some of the accelerating cavities. Particle tracking of the expected dark current through the entire LCLS linac, from gun through FEL undulator, is used to estimate final particle extent in the undulator as well as expected beam loss at each collimator or aperture restriction. A table of collimators and aperture restrictions is listed along with halo particle loss results, which includes an estimate of average continuous beam power lost. In addition, the transverse wakefield alignment tolerances are calculated for each collimator.

  8. Status of the Linac Coherent Light Source

    SciTech Connect

    Galayda, John N.; /SLAC

    2011-11-04

    The Linac Coherent Light Source (LCLS) is a free electron laser facility in construction at Stanford Linear Accelerator Center. It is designed to operate in the wavelength range 0.15-1.5 nanometers. At the time of this conference, civil construction of new tunnels and buildings is complete, the necessary modifications to the SLAC linac are complete, and the undulator system and x-ray optics/diagnostics are being installed. The electron gun, 135 MeV injector linac and 250 MeV bunch compressor were commissioned in 2007. Accelerator commissioning activities are presently devoted to the achievement of performance goals for the completed 14 GeV linac.

  9. Optical microscopy using a single-molecule light source

    PubMed

    Michaelis; Hettich; Mlynek; Sandoghdar

    2000-05-18

    Rapid progress in science on nanoscopic scales has promoted increasing interest in techniques of ultrahigh-resolution optical microscopy. The diffraction limit can be surpassed by illuminating an object in the near field through a sub-wavelength aperture at the end of a sharp metallic probe. Proposed modifications of this technique involve replacing the physical aperture by a nanoscopic active light source. Advances in the spatial and spectral detection of individual fluorescent molecules, using near-field and far-field methods, suggest the possibility of using a single molecule as the illumination source. Here we present optical images taken with a single molecule as a point-like source of illumination, by combining fluorescence excitation spectroscopy with shear-force microscopy. Our single-molecule probe has potential for achieving molecular resolution in optical microscopy; it should also facilitate controlled studies of nanometre-scale phenomena (such as resonant energy transfer) with improved lateral and axial spatial resolution.

  10. Status of the Synchrotron Light Source DELTA

    SciTech Connect

    Berges, U.; Sternemann, C.; Tolan, M.; Westphal, C.; Weis, T.; Wille, K.

    2007-01-19

    The Dortmund Electron Accelerator DELTA, a 1.5 GeV synchrotron light source located at University of Dortmund, is operated for 3000 h per year including 2000 h beam time for synchrotron radiation use and 1000 h for machine physics, optimisation and maintenance. The status of the synchrotron light source is presented with emphasis on the operation, commissioning and installation of beamlines and insertion devices. The soft X-ray undulator beamlines provide photon energies between 5 to 400 eV (U250) and 55 and 1500 eV (U55), respectively. One dipole beamline covers soft X-rays between 6 to 200 eV, and a second dipole beamline is used without a monochromator at 2.2 keV critical energy of the dipole spectrum. For photons in the hard X-ray regime, a superconducting asymmetric wiggler (SAW) with a field of 5.3 T and 7.9 keV critical energy was installed, providing circularly polarized X-rays in the range of 2 to 30 keV. Due to its broad radiation fan, three beamlines are simultaneously served. The first SAW-beamline with an energy range between 4 to 30 keV is in full operation, the second is under commissioning, serving the energy range between 2 to 30 keV. The third SAW beamline is near completion, additional dipole beamlines are under construction.

  11. Advanced Solid State Lighting for Human Evaluation Project

    NASA Technical Reports Server (NTRS)

    Zeitlin, Nancy; Holbert, Eirik

    2015-01-01

    Lighting intensity and color have a significant impact on human circadian rhythms. Advanced solid state lighting was developed for the Advanced Exploration System (AES) Deep Space Habitat(DSH) concept demonstrator. The latest generation of assemblies using the latest commercially available LED lights were designed for use in the Bigelow Aerospace Environmental Control and Life Support System (ECLSS) simulator and the University of Hawaii's Hawaii Space Exploration Analog and Simulation (Hi-SEAS) habitat. Agreements with both these organizations will allow the government to receive feedback on the lights and lighting algorithms from long term human interaction.

  12. Light

    NASA Astrophysics Data System (ADS)

    Vernon, C. G.

    2016-09-01

    Preface; 1. Historical; 2. Waves and wave-motion; 3. The behaviour of ripples; 4. The behaviour of light; 5. Refraction through glass blocks and prisms; 6. The imprinting of curvatures; 7. Simple mathematical treatment; 8. More advanced mathematical treatment; 9. The velocity of light; 10. The spectrum and colour; 11. Geometrical optics; 12. The eye and optical instruments; 13. Sources of light; 14. Interference, diffraction and polarisation; 15. Suggestions for class experiments; Index.

  13. The Advanced Neutron Source liquid deuterium cold source

    SciTech Connect

    Lucas, A.T.

    1995-08-01

    The Advanced Neutron Source will employ two cold sources to moderate neutrons to low energy (<10 meV). The cold neutrons produced are then passed through beam guides to various experiment stations. Each cold source moderator is a sphere of 410-mm internal diameter. The moderator material is liquid deuterium flowing at a rate of 1 kg/s and maintained at subcooled temperatures at all points of the circuit, to prevent boiling. Nuclear beat deposited within the liquid deuterium and its containment structure totals more than 30 kW. All of this heat is removed by the liquid deuterium, which raises its temperature by 5 K. The liquid prime mover is a cryogenic circulator that is situated in the return leg of the flow loop. This arrangement minimizes the heat added to the liquid between the heat exchanger and the moderator vessel, allowing the moderator to be operated at the minimum practical temperature. This report describes the latest thinking at the time of project termination. It also includes the status of various systems at that time and outlines anticipated directions in which the design would have progressed. In this regard, some detail differences between this report and official design documents reflect ideas that were not approved at the time of closure but are considered noteworthy.

  14. Status of SESAME Synchrotron Light Source

    NASA Astrophysics Data System (ADS)

    Tarawneh, Hamed

    2013-04-01

    During this presentation, I will talk about the current status of the SESAME synchrotron radiation source (SESAME: Synchrotron light for Experimental Science and Application in the Middle East). SESAME is an international research center located in Allan, Jordan and the accelerator complex consists of new storage ring of an energy of 2.5 GeV injected at 800 MeV and the injector is based on the upgraded 22.5 MeV Microtron and 800 MeV booster from the BESSY-I machine donated by Germany. The results of the design work and the optimizations of the beam optics for the SESAME storage ring and booster accelerators' lattices will be presented. I will also report on the status of the storage ring main sub-systems and the scientific case of the SESAME facility with the planned day-one beamlines.

  15. ENERGY SOURCES AND LIGHT CURVES OF MACRONOVAE

    SciTech Connect

    Kisaka, Shota; Ioka, Kunihito; Takami, Hajime E-mail: takami@post.kek.jp

    2015-04-01

    A macronova (kilonova) was discovered with a short gamma-ray burst, GRB 130603B, which is widely believed to be powered by the radioactivity of r-process elements synthesized in the ejecta of a neutron star (NS)–binary merger. As an alternative, we propose that macronovae are energized by the central engine, i.e., a black hole or NS, and the injected energy is emitted after the adiabatic expansion of ejecta. This engine model is motivated by extended emission of short GRBs. In order to compare the theoretical models with observations, we develop analytical formulae for the light curves of macronovae. The engine model allows a wider parameter range, especially smaller ejecta mass, and a better fit to observations than the r-process model. Future observations of electromagnetic counterparts of gravitational waves should distinguish energy sources and constrain the activity of the central engine and the r-process nucleosynthesis.

  16. Status of the SAGA Light Source

    SciTech Connect

    Kaneyasu, T.; Takabayashi, Y.; Iwasaki, Y.; Koda, S.

    2010-06-23

    The SAGA Light Source (SAGA-LS) is a synchrotron radiation facility consisting of a 255 MeV injector linac and a 1.4 GeV storage ring that is 75.6 m in circumference. The SAGA-LS has been stably providing synchrotron radiation to users since it first started user operation in February 2006. Along with the user operation, various machine improvements have been made over the past years, including upgrading the injector linac control system, replacing a septum magnet and constructing a beam diagnostic system. In addition to these improvements, insertion devices have been developed and installed. An APPLE-II type variable polarization undulator was installed in 2008. To address the demand from users for high-flux hard x-rays, a superconducting 4 T class wiggler is being developed. An experimental setup for generating MeV photons by laser Compton scattering is being constructed for beam monitoring and future user experiments.

  17. Integrated source of broadband quadrature squeezed light.

    PubMed

    Hoff, Ulrich B; Nielsen, Bo M; Andersen, Ulrik L

    2015-05-04

    An integrated silicon nitride resonator is proposed as an ultra-compact source of bright single-mode quadrature squeezed light at 850 nm. Optical properties of the device are investigated and tailored through numerical simulations, with particular attention paid to loss associated with interfacing the device. An asymmetric double layer stack waveguide geometry with inverse vertical tapers is proposed for efficient and robust fibre-chip coupling, yielding a simulated total loss of -0.75 dB/facet. We assess the feasibility of the device through a full quantum noise analysis and derive the output squeezing spectrum for intra-cavity pump self-phase modulation. Subject to standard material loss and detection efficiencies, we find that the device holds promises for generating substantial quantum noise squeezing over a bandwidth exceeding 1 GHz. In the low-propagation loss regime, approximately -6 dB squeezing is predicted for a pump power of only 75 mW.

  18. The Advanced Photon Source list of parameters

    SciTech Connect

    Bizek, H.M.

    1996-07-01

    The Advanced Photon Source (APS) is a third-generation synchrotron radiation source that stores positrons in a storage ring. The choice of positrons as accelerating particles was motivated by the usual reason: to eliminate the degradation of the beam caused by trapping of positively charged dust particles or ions. The third-generation synchrotron radiation sources are designed to have low beam emittance and many straight sections for insertion devices. The parameter list is comprised of three basic systems: the injection system, the storage ring system, and the experimental facilities system. The components of the injection system are listed according to the causal flow of positrons. Below we briefly list the individual components of the injection system, with the names of people responsible for managing these machines in parentheses: the linac system; electron linac-target-positron linac (Marion White); low energy transport line from linac to the PAR (Michael Borland); positron accumulator ring or PAR (Michael Borland); low energy transport line from PAR to injector synchrotron (Michael Borland); injector synchrotron (Stephen Milton); high energy transport line from injector synchrotron to storage ring (Stephen Milton). The storage ring system, managed by Glenn Decker, uses the Chasman-Green lattice. The APS storage ring, 1104 m in circumference, has 40 periodic sectors. Six are used to house hardware and 34 serve as insertion devices. Another 34 beamlines emit radiation from bending magnets. The experimental facilities system`s parameters include parameters for both an undulator and a wiggler.

  19. Status of the Advanced Photon Source

    NASA Astrophysics Data System (ADS)

    Gerig, R. E.; Gibson, J. M.; Mills, D. M.; Ruzicka, W. G.; Young, L.; Zholents, A.

    2011-09-01

    In the fall of 2010, the Advanced Photon Source (APS) will enter its fifteenth year of user operations. During fiscal year 2009, the APS delivered X-ray beam to the scientific community 97.7% of scheduled hours (availability) and with a mean time between faults of 77.5 h. The APS remains the most prolific source worldwide of structure deposits in the Protein Data Bank (1433 in 2009) and a leader in the field of high-pressure research, among others. However, to maintain its position as a state-of-the-art facility for hard X-ray science, it will be necessary to refresh and improve the APS X-ray source and beamlines. We are presently on the path to do that through the APS Upgrade Project. The US Department of Energy Office of Science has formally approved the start of this project with the issuance of Critical Decision-0, Approve of Mission Need. The APS staff, in collaboration with our user community, is now in the process of developing a Conceptual Design Report that documents the proposed scope of the APS Upgrade Project. Components of the Upgrade plan will be presented as well as science highlights from the past year.

  20. LED intense headband light source for fingerprint analysis

    DOEpatents

    Villa-Aleman, Eliel

    2005-03-08

    A portable, lightweight and high-intensity light source for detecting and analyzing fingerprints during field investigation. On-site field analysis requires long hours of mobile analysis. In one embodiment, the present invention comprises a plurality of light emitting diodes; a power source; and a personal attachment means; wherein the light emitting diodes are powered by the power source, and wherein the power source and the light emitting diodes are attached to the personal attachment means to produce a personal light source for on-site analysis of latent fingerprints. The present invention is available for other applications as well.

  1. Advances and synergy of high pressure sciences at synchrotron sources

    SciTech Connect

    Liu, H.; Ehm, L.; Duffy, T.; Crichton, W.; Aoki, K.

    2009-01-01

    Introductory overview to the special issue papers on high-pressure sciences and synchrotron radiation. High-pressure research in geosciences, materials science and condensed matter physics at synchrotron sources is experiencing growth and development through synergistic efforts around the world. A series of high-pressure science workshops were organized in 2008 to highlight these developments. One of these workshops, on 'Advances in high-pressure science using synchrotron X-rays', was held at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, USA, on 4 October 2008. This workshop was organized in honour of Drs Jingzhu Hu and Quanzhong Guo in celebration of their retirement after up to 18 years of dedicated service to the high-pressure community as beamline scientists at X17 of NSLS. Following this celebration of the often unheralded role of the beamline scientist, a special issue of the Journal of Synchrotron Radiation on Advances and Synergy of High-Pressure Sciences at Synchrotron Sources was proposed, and we were pleased to invite contributions from colleagues who participated in the workshop as well as others who are making similar efforts at synchrotron sources worldwide.

  2. Diamond Light Source: status and perspectives.

    PubMed

    Materlik, Gerhard; Rayment, Trevor; Stuart, David I

    2015-03-06

    Diamond Light Source, a third-generation synchrotron radiation (SR) facility in the UK, celebrated its 10th anniversary in 2012. A private limited company was set up in April 2002 to plan, construct and operate the new user-oriented SR facility, called in brief Diamond. It succeeded the Synchrotron Radiation Source in Daresbury, a second-generation synchrotron that opened in 1980 as the world's first dedicated X-ray-providing facility, closing finally in 2008, by which time Diamond's accelerators and first beamlines were operating and user experiments were under way. This theme issue of Philosophical Transactions of the Royal Society A gives some examples of the rich diversity of research done in the initial five years, with some glimpses of activity up to 2014. Speakers at the 10 year anniversary symposium were drawn from a small number of major thematic areas and each theme was elaborated by a few speakers whose contributions were placed into a broader context by a leading member of the UK academic community in the role of rapporteur. This introduction gives a summary of the design choices and strategic planning of Diamond as a coherent user facility, a snapshot of its present status and some consideration of future perspectives.

  3. Status of the Metrology Light Source

    NASA Astrophysics Data System (ADS)

    Klein, R.; Ulm, G.; Feikes, J.; Hartrott, M. v.; Wüstefeld, G.

    2010-06-01

    The Physikalisch-Technische Bundesanstalt (PTB), the German national metrology institute, has set up the low-energy electron storage ring Metrology Light Source (MLS) in close cooperation with the Helmholtz-Zentrum Berlin (HZB, formerly BESSY). This new storage ring has been in regular user operation since April 2008 and is dedicated to synchrotron-radiation-based metrology and technological developments in the far-IR/THz, IR, UV, VUV and EUV spectral range. The MLS has a double-bend-achromate lattice structure, injection is from a 105 MeV racetrack microtron. The electron energy can be ramped to any value from 105 MeV up to 630 MeV and the electron beam current covers the range from one stored electron (1 pA) up to 200 mA. The MLS is the first electron storage ring optimized for the generation of coherent synchrotron radiation, based on an electron bunch shortening mode. In this mode, MLS delivers coherent radiation in the far-IR/THz spectral range with enhanced intensity as compared to the normal mode of operation. Several beamlines are in operation or in construction, including one undulator beamline, bending magnet beamlines for the calibration of radiation sources and detectors and for reflectometry, an EUV metrology beamline and three IR/THz beamlines.

  4. Diamond Light Source: status and perspectives

    PubMed Central

    Materlik, Gerhard; Rayment, Trevor; Stuart, David I.

    2015-01-01

    Diamond Light Source, a third-generation synchrotron radiation (SR) facility in the UK, celebrated its 10th anniversary in 2012. A private limited company was set up in April 2002 to plan, construct and operate the new user-oriented SR facility, called in brief Diamond. It succeeded the Synchrotron Radiation Source in Daresbury, a second-generation synchrotron that opened in 1980 as the world's first dedicated X-ray-providing facility, closing finally in 2008, by which time Diamond's accelerators and first beamlines were operating and user experiments were under way. This theme issue of Philosophical Transactions of the Royal Society A gives some examples of the rich diversity of research done in the initial five years, with some glimpses of activity up to 2014. Speakers at the 10 year anniversary symposium were drawn from a small number of major thematic areas and each theme was elaborated by a few speakers whose contributions were placed into a broader context by a leading member of the UK academic community in the role of rapporteur. This introduction gives a summary of the design choices and strategic planning of Diamond as a coherent user facility, a snapshot of its present status and some consideration of future perspectives. PMID:25624517

  5. The Advanced Photon Source control system

    SciTech Connect

    Knott, M.J.; McDowell, W.P.; Lenkszus, F.R.; Kraimer, M.R.; Arnold, N.D.; Daly, R.T.; Gunderson, G.R.; Cha, Ben-Chin K.; Anderson, M.D.

    1991-01-01

    The Advanced Photon Source (APS), now under construction at Argonne National Laboratory (ANL), is a 7-GeV positron storage ring dedicated to research facilities using synchrotron radiation. This ring, along with its injection accelerators is to be controlled and monitored with a single, flexible and expandable control system. The control system must be capable of operating the APS storage ring alone, and in conjunction with its injector synchrotron for filling, as well as operating both storage ring and injection facilities as machines with separate missions. The control system design is based on the (now classic) precepts of high-performance workstations as operators consoles, distributed microprocessors to control equipment interfacing and preprocess data, and an interconnecting network. The current design includes about 45 distributed microprocessors and five console systems, which may consist of one or more workstations. 6 refs., 2 figs.

  6. Advanced neutron source materials surveillance program

    SciTech Connect

    Heavilin, S.M.

    1995-01-01

    The Advanced Neutron Source (ANS) will be composed of several different materials, one of which is 6061-T6 aluminum. Among other components, the reflector vessel and the core pressure boundary tube (CPBT), are to be made of 6061-T6 aluminum. These components will be subjected to high thermal neutron fluences and will require a surveillance program to monitor the strength and fracture toughness of the 6061-T6 aluminum over their lifetimes. The purpose of this paper is to explain the steps that were taken in the summer of 1994 toward developing the surveillance program. The first goal was to decide upon standard specimens to use in the fracture toughness and tensile testing. Second, facilities had to be chosen for specimens representing the CPBT and the reflector vessel base, weld, and heat-affected-zone (HAZ) metals. Third, a timetable had to be defined to determine when to remove the specimens for testing.

  7. The 4th Generation Light Source at Jefferson Lab

    SciTech Connect

    Stephen Benson; George Biallas; James Boyce; Donald Bullard; James Coleman; David Douglas; H. Dylla; Richard Evans; Pavel Evtushenko; Albert Grippo; Christopher Gould; Joseph Gubeli; David Hardy; Carlos Hernandez-Garcia; Kevin Jordan; John Klopf; Steven Moore; George Neil; Thomas Powers; Joseph Preble; Daniel Sexton; Michelle D. Shinn; Christopher Tennant; Richard Walker; Shukui Zhang; Gwyn Williams

    2007-04-25

    A number of "Grand Challenges" in Science have recently been identified in reports from The National Academy of Sciences, and the U.S. Dept. of Energy, Basic Energy Sciences. Many of these require a new generation of linac-based light source to study dynamical and non-linear phenomena in nanoscale samples. In this paper we present a summary of the properties of such light sources, comparing them with existing sources, and then describing in more detail a specific source at Jefferson Lab. Importantly, the JLab light source has developed some novel technology which is a critical enabler for other new light sources.

  8. National Synchrotron Light Source 2008 Activity Report

    SciTech Connect

    Nasta,K.

    2009-05-01

    Funded by the U.S. Department of Energy's Office of Basic Energy Sciences, the National Synchrotron Light Source (NSLS) is a national user facility that operates two electron storage rings: X-Ray (2.8 GeV, 300 mA) and Vacuum Ultraviolet (VUV) (800 mev, 1.0A). These two rings provide intense light spanning the electromagnetic spectrum -- from very long infrared rays to ultraviolet light and super-short x-rays -- to analyze very small or highly dilute samples. The properties of this light, and the specially designed experimental stations, called beamlines, allow scientists in many diverse disciplines of research to perform experiments not possible at their own laboratories. Each year, about 2,200 scientists from more than 400 universities and companies use the NSLS for research in such diverse fields as biology, physics, chemistry, geology, medicine, and environmental and materials sciences. For example, researchers have used the NSLS to examine the minute details of computer chips, decipher the structures of viruses, probe the density of bone, determine the chemical composition of moon rocks, and reveal countless other mysteries of science. The facility has 65 operating beamlines, with 51 beamlines on the X-Ray Ring and 14 beamlines on the VUV-Infrared Ring. It runs seven days a week, 24 hours a day throughout the year, except during periods of maintenance and studies. Researchers are not charged for beam time, provided that the research results are published in open literature. Proprietary research is conducted on a full-cost-recovery basis. With close to 1,000 publications per year, the NSLS is one of the most prolific scientific facilities in the world. Among the many accolades given to its users and staff, the NSLS has won nine R&D 100 Awards for innovations ranging from a closed orbit feedback system to the first device able to focus a large spread of high-energy x-rays. In addition, a visiting NSLS researcher shared the 2003 Nobel Prize in Chemistry for work

  9. The Sun: the Earth light source

    NASA Astrophysics Data System (ADS)

    Berrilli, Francesco; Giovannelli, Luca; Del Moro, Dario; Piazzesi, Roberto; Catena, Liu` Maria; Amicucci, Giordano; Vittorio, Nicola

    2015-04-01

    We have implemented at Department of Physics of University of Rome Tor Vergata a project called "The Sun: the Earth light source". The project obtained the official endorsement from the IAU Executive Committee Working Group for the International Year of Light. The project, specifically designed for high school students, is focused on the "scientific" study of Sun light by means of a complete acquisition system based on "on the shelf" appropriately CMOS low-cost sensor with free control s/w and self-assembled telescopes. The project (hereafter stage) plan is based on a course of two weeks (60 hours in total). The course contains 20 hours of theoretical lectures, necessary to learn basics about Sun, optics, telescopes and image sensors, and 40 hours of laboratory. During the course, scientists and astronomers share with high schools students, work activities in real research laboratories. High schools teachers are intensely involved in the project. Their role is to share activities with university teachers and realize outreach actions in the home institutions. Simultaneously, they are introduced to innovative teaching methods and the project in this way is regarded as a professional development course. Sun light analysis and Sun-Earth connection through light are the main scientific topics of this project. The laboratory section of the stage is executed in two phases (weeks): First phase aims are the realization of a keplerian telescope and low-cost acquisition system. During this week students are introduced to astronomical techniques used to safety collect and acquire solar light; Second phase aims is the realization of a low-cost instrument to analyse sunlight extracting information about the solar spectrum, solar irradiance and Sun-Earth connection. The proposed stage has been already tested in Italy reached the fifth edition in 2014. Since 2010, the project has been a cornerstone outreach program of the University of Rome Tor Vergata, the Italian Ministry of

  10. LIGHT SOURCE: TW Laser system for Thomson scattering X-ray light source at Tsinghua University

    NASA Astrophysics Data System (ADS)

    Yan, Li-Xm; Du, Ying-Chao; Du, Qiang; Li, Ren-Kai; Hua, Jian-Fei; Huang, Wen-Hui; Tang, Chuan-Xiang

    2009-06-01

    A TW (Tera Watt) laser system based on Ti:sapphire mainly for the Tsinghua Thomson scattering X-ray light source (TTX) is being built. Both UV (ultraviolet) laser pulse for driving the photocathode radio-frequency (RF) gun and the IR (infrared) laser pulse as the electron-beam-scattered-light are provided by the system. Efforts have also been made in laser pulse shaping and laser beam transport to optimize the high-brightness electron beam production by the photocathode RF gun.

  11. Broiler performance when reared under various light sources.

    PubMed

    Zimmermann, N G

    1988-01-01

    Three trials were conducted to determine if modern energy-efficient light sources, which vary in wavelength emission, affect broiler growth performance. The effect of light source on growth performance was determined by measuring body weight, feed conversion, and livability at intervals throughout rearing and at market age in three flocks of approximately 3,600 broilers each. Illuminance within the light-proof experimental facility was approximately 5 1x and photoregimen was 1 h dark:23 h light. Trial 1 compared incandescent (IN), warm white fluorescent (WWF), and daylight fluorescent (DLF) light sources. The WWF source provided superior body weight compared to IN light but feed conversion ratios were similar. Both IN and WWF light sources resulted in better body weight and feed conversion than that of the DLF light source. Trial 2 used IN, WWF, DLF, PL-5 fluorescent (PLF), design white fluorescent (DWF), and high pressure sodium (HPS) light sources. The PLF source resulted in mean body weight significantly higher than those produced by IN, HPS, and DWF. No other significant differences were observed. Trial 3 used IN, WWF, DLF, PLF, HPS, and low pressure sodium (LPS) light sources. Feed conversion for the HPS treatment was superior to that of PLF and LPS treatments. No other significant differences were observed. Light source did not affect livability in any of the trials. These trials demonstrated that energy-efficient light sources varying in wavelength emission may affect broiler growth performance, but consistent differences were not observed. Generally, IN light sources may be replaced with more energy-efficient light sources without adverse effects on broiler growth performance.

  12. The Jefferson Lab High Power Light Source

    SciTech Connect

    James R. Boyce

    2006-01-01

    Jefferson Lab has designed, built and operated two high average power free-electron lasers (FEL) using superconducting RF (SRF) technology and energy recovery techniques. Between 1999-2001 Jefferson Lab operated the IR Demo FEL. This device produced over 2 kW in the mid-infrared, in addition to producing world record average powers in the visible (50 W), ultraviolet (10 W) and terahertz range (50 W) for tunable, short-pulse (< ps) light. This FEL was the first high power demonstration of an accelerator configuration that is being exploited for a number of new accelerator-driven light source facilities that are currently under design or construction. The driver accelerator for the IR Demo FEL uses an Energy Recovered Linac (ERL) configuration that improves the energy efficiency and lowers both the capital and operating cost of such devices by recovering most of the power in the spent electron beam after optical power is extracted from the beam. The IR Demo FEL was de-commissioned in late 2001 for an upgraded FEL for extending the IR power to over 10 kW and the ultraviolet power to over 1 kW. The FEL Upgrade achieved 10 kW of average power in the mid-IR (6 microns) in July of 2004, and its IR operation currently is being extended down to 1 micron. In addition, we have demonstrated the capability of on/off cycling and recovering over a megawatt of electron beam power without diminishing machine performance. A complementary UV FEL will come on-line within the next year. This paper presents a summary of the FEL characteristics, user community accomplishments with the IR Demo, and planned user experiments.

  13. Photocathodes for High Repetition Rate Light Sources

    SciTech Connect

    Ben-Zvi, Ilan

    2014-04-20

    This proposal brought together teams at Brookhaven National Laboratory (BNL), Lawrence Berkeley National Laboratory (LBNL) and Stony Brook University (SBU) to study photocathodes for high repetition rate light sources such as Free Electron Lasers (FEL) and Energy Recovery Linacs (ERL). Below details the Principal Investigators and contact information. Each PI submits separately for a budget through his corresponding institute. The work done under this grant comprises a comprehensive program on critical aspects of the production of the electron beams needed for future user facilities. Our program pioneered in situ and in operando diagnostics for alkali antimonide growth. The focus is on development of photocathodes for high repetition rate Free Electron Lasers (FELs) and Energy Recovery Linacs (ERLs), including testing SRF photoguns, both normal-­conducting and superconducting. Teams from BNL, LBNL and Stony Brook University (SBU) led this research, and coordinated their work over a range of topics. The work leveraged a robust infrastructure of existing facilities and the support was used for carrying out the research at these facilities. The program concentrated in three areas: a) Physics and chemistry of alkali-­antimonide cathodes (BNL – LBNL) b) Development and testing of a diamond amplifier for photocathodes (SBU -­ BNL) c) Tests of both cathodes in superconducting RF photoguns (SBU) and copper RF photoguns (LBNL) Our work made extensive use of synchrotron radiation materials science techniques, such as powder-­ and single-­crystal diffraction, x-­ray fluorescence, EXAFS and variable energy XPS. BNL and LBNL have many complementary facilities at the two light sources associated with these laboratories (NSLS and ALS, respectively); use of these will be a major thrust of our program and bring our understanding of these complex materials to a new level. In addition, CHESS at Cornell will be used to continue seamlessly throughout the NSLS dark period and

  14. Advanced Solid State Lighting for AES Deep Space Hab Project

    NASA Technical Reports Server (NTRS)

    Holbert, Eirik

    2015-01-01

    The advanced Solid State Lighting (SSL) assemblies augmented 2nd generation modules under development for the Advanced Exploration Systems Deep Space Habitat in using color therapy to synchronize crew circadian rhythms. Current RGB LED technology does not produce sufficient brightness to adequately address general lighting in addition to color therapy. The intent is to address both through a mix of white and RGB LEDs designing for fully addressable alertness/relaxation levels as well as more dramatic circadian shifts.

  15. High Pressure Microwave Powered UV Light Sources

    NASA Astrophysics Data System (ADS)

    Cekic, M.; Frank, J. D.; Popovic, S.; Wood, C. H.

    1997-10-01

    Industrial microwave powered (*electrodeless*) light sources have been limited to quiescent pressures of 300 Torr of buffer gas and metal- halide fills. Recently developed multi-atmospheric electronegative bu lb fills (noble gas-halide excimers, metal halide) require electric field s for ionization that are often large multiples of the breakdown voltage for air. For these fills an auxiliary ignition system is necessary. The most successful scheme utilizes a high voltage pulse power supply and a novel field emission source. Acting together they create localized condition of pressure reduction and high free electron density. This allows the normal microwave fields to drive this small region into avalanche, ignite the bulb, and heat the plasma to it's operating poin t Standard diagnostic techniques of high density discharges are inapplicable to the excimer bulbs, because of the ionic molecular exci ted state structure and absence of self-absorption. The method for temperature determination is based on the equilibrium population of certain vibrational levels of excimer ionic excited states. Electron d ensity was determined from the measurements of Stark profiles of H_β radiation from a small amount of hydrogen mixed with noble gas and halogens. At the present time, high pressure (Te 0.5eV, ne 3 x 10^17 cm-3) production bulbs produce over 900W of radiation in a 30nm band, centered at 30nm. Similarly, these prototypes when loaded with metal-halide bulb fills produce 1 kW of radiation in 30nm wide bands, centered about the wavelength of interest.

  16. Status Of The Synchrotron Light Source DELTA

    SciTech Connect

    Berges, U.; Friedl, J.; Hartmann, P.; Schirmer, D.; Schmidt, G.; Sternemann, C.; Tolan, M.; Weis, T.; Westphal, C.; Wille, K.

    2004-05-12

    The Dortmund Electron Accelerator DELTA, located at the University of Dortmund, changed its scope during the last years into a 1.5 GeV synchrotron light source. DELTA is now operated for 3000 h per year including 2000 h dedicated beam time for synchrotron radiation use and 1000 h for machine physics, optimization and maintenance. The status of the accelerator complex is presented together with the beam operation, the installation and commissioning of beamlines and insertion devices. To serve user demands of photon energies up to more than 10 keV a 5.3 T superconducting asymmetric multipole wiggler (SAW) with a critical energy of 7.9 keV has been installed serving three beamlines in the hard X-ray regime with also circular polarization. Two undulator beamlines for photon energies between 5 and 400 eV (U250) and between 55 and 1500 eV (U55) and several dipole beamlines up to 200 eV are under operation. The construction and operation of the different beamlines is done by various universities and laboratories in Nordrhein-Westfalen.

  17. Advanced Source Deconvolution Methods for Compton Telescopes

    NASA Astrophysics Data System (ADS)

    Zoglauer, Andreas

    The next generation of space telescopes utilizing Compton scattering for astrophysical observations is destined to one day unravel the mysteries behind Galactic nucleosynthesis, to determine the origin of the positron annihilation excess near the Galactic center, and to uncover the hidden emission mechanisms behind gamma-ray bursts. Besides astrophysics, Compton telescopes are establishing themselves in heliophysics, planetary sciences, medical imaging, accelerator physics, and environmental monitoring. Since the COMPTEL days, great advances in the achievable energy and position resolution were possible, creating an extremely vast, but also extremely sparsely sampled data space. Unfortunately, the optimum way to analyze the data from the next generation of Compton telescopes has not yet been found, which can retrieve all source parameters (location, spectrum, polarization, flux) and achieves the best possible resolution and sensitivity at the same time. This is especially important for all sciences objectives looking at the inner Galaxy: the large amount of expected sources, the high background (internal and Galactic diffuse emission), and the limited angular resolution, make it the most taxing case for data analysis. In general, two key challenges exist: First, what are the best data space representations to answer the specific science questions? Second, what is the best way to deconvolve the data to fully retrieve the source parameters? For modern Compton telescopes, the existing data space representations can either correctly reconstruct the absolute flux (binned mode) or achieve the best possible resolution (list-mode), both together were not possible up to now. Here we propose to develop a two-stage hybrid reconstruction method which combines the best aspects of both. Using a proof-of-concept implementation we can for the first time show that it is possible to alternate during each deconvolution step between a binned-mode approach to get the flux right and a

  18. Radioluminescent light source for the development of optical sensor arrays.

    PubMed

    Holthoff, William G; Tehan, Elizabeth C; Bukowski, Rachel M; Kent, Nigel; Maccraith, Brian D; Bright, Frank V

    2005-01-15

    A radioluminescent (RL) light source is evaluated for the development of photonically based chemical-responsive sensor arrays (CRSAs). The RL light source is comprised of a strontium-90 (90Sr) radionuclide and a plastic scintillator. The beta particles emitted from the 90Sr generate blue light (lambda(max) = 435 nm) from the plastic scintillator, and the blue light excites the analyte-responsive luminophores within the CRSA. To assess the RL light source utility, we have determined the analytical figures of merit from two tris(4,7'-diphenyl-1,10'-phenathroline)ruthenium(II)-doped xerogel-based sensor platforms: (i) a planar 5 x 5 multielement array and (ii) a discrete sensor element formed on the proximal face of poly(styrene) pillars that have a frustrated cone (frustum) geometry. We compare the performance from each platform when it is excited by a He-Cd laser (442 nm), a blue light-emitting diode (460-470 nm), and the RL light source. The RL light source yields results that are statistically equivalent to results from either electrically powered light source. The RL light source consumes no electrical power, is compact and simple, and has an extremely stable time-averaged signal. The primary trade-offs for these advantages are the RL light source's lower radiant power and the corresponding longer data acquisition times.

  19. Filter selection based on light source for multispectral imaging

    NASA Astrophysics Data System (ADS)

    Xu, Peng; Xu, Haisong

    2016-07-01

    In multispectral imaging, it is necessary to select a reduced number of filters to balance the imaging efficiency and spectral reflectance recovery accuracy. Due to the combined effect of filters and light source on reflectance recovery, the optimal filters are influenced by the employed light source in the multispectral imaging system. By casting the filter selection as an optimization issue, the selection of optimal filters corresponding to the employed light source proceeds with respect to a set of target samples utilizing one kind of genetic algorithms, regardless of the detailed spectral characteristics of the light source, filters, and sensor. Under three light sources with distinct spectral power distributions, the proposed filter selection method was evaluated on a filter-wheel based multispectral device with a set of interference filters. It was verified that the filters derived by the proposed method achieve better spectral and colorimetric accuracy of reflectance recovery than the conventional one under different light sources.

  20. Advanced power sources for space missions

    NASA Technical Reports Server (NTRS)

    Gavin, Joseph G., Jr.; Burkes, Tommy R.; English, Robert E.; Grant, Nicholas J.; Kulcinski, Gerald L.; Mullin, Jerome P.; Peddicord, K. Lee; Purvis, Carolyn K.; Sarjeant, W. James; Vandevender, J. Pace

    1989-01-01

    Approaches to satisfying the power requirements of space-based Strategic Defense Initiative (SDI) missions are studied. The power requirements for non-SDI military space missions and for civil space missions of the National Aeronautics and Space Administration (NASA) are also considered. The more demanding SDI power requirements appear to encompass many, if not all, of the power requirements for those missions. Study results indicate that practical fulfillment of SDI requirements will necessitate substantial advances in the state of the art of power technology. SDI goals include the capability to operate space-based beam weapons, sometimes referred to as directed-energy weapons. Such weapons pose unprecedented power requirements, both during preparation for battle and during battle conditions. The power regimes for these two sets of applications are referred to as alert mode and burst mode, respectively. Alert-mode power requirements are presently stated to range from about 100 kW to a few megawatts for cumulative durations of about a year or more. Burst-mode power requirements are roughly estimated to range from tens to hundreds of megawatts for durations of a few hundred to a few thousand seconds. There are two likely energy sources, chemical and nuclear, for powering SDI directed-energy weapons during the alert and burst modes. The choice between chemical and nuclear space power systems depends in large part on the total duration during which power must be provided. Complete study findings, conclusions, and eight recommendations are reported.

  1. Advanced Neutron Sources: Plant Design Requirements

    SciTech Connect

    Not Available

    1990-07-01

    The Advanced Neutron Source (ANS) is a new, world class facility for research using hot, thermal, cold, and ultra-cold neutrons. At the heart of the facility is a 350-MW{sub th}, heavy water cooled and moderated reactor. The reactor is housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides fans out into a large guide hall, housing about 30 neutron research stations. Office, laboratory, and shop facilities are included to provide a complete users facility. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory at the end of the decade. This Plant Design Requirements document defines the plant-level requirements for the design, construction, and operation of the ANS. This document also defines and provides input to the individual System Design Description (SDD) documents. Together, this Plant Design Requirements document and the set of SDD documents will define and control the baseline configuration of the ANS.

  2. Advanced Neutron Source: Plant Design Requirements

    SciTech Connect

    Not Available

    1990-07-01

    The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and control the baseline configuration of ANS.

  3. Atomic physics at the advanced photon source

    SciTech Connect

    Berry, H.G.; Cowan, P.L.; Gemmell, D.S.

    1995-08-01

    Argonne`s 7-GeV synchrotron light source (APS) is expected to commence operations for research early in FY 1996. The Basic Energy Sciences Synchrotron Research Center (BESSRC) is likewise expected to start its research programs at that time. As members of the BESSRC CAT (Collaborative Access Team), we are preparing, together with atomic physicists from the University of Western Michigan, the University of Tennessee, and University of Notre Dame, to initiate a series of atomic physics experiments that exploit the unique capabilities of the APS, especially its high brilliance for photon energies extending from about 3 keV to more than 50 keV. Most of our early work will be conducted on an undulator beam line and we are thus concentrating on various aspects of that beam line and its associated experimental areas. Our group has undertaken responsibilities in such areas as hutch design, evaluation of undulator performance, user policy, interfacing and instrumentation, etc. Initial experiments will probably utilize existing apparatus. We are, however, planning to move rapidly to more sophisticated measurements involving, for example, ion-beam targets, simultaneous laser excitation, and the spectroscopy of emitted photons.

  4. Advances and prospects in visible light communications

    NASA Astrophysics Data System (ADS)

    Hongda, Chen; Chunhui, Wu; Honglei, Li; Xiongbin, Chen; Zongyu, Gao; Shigang, Cui; Qin, Wang

    2016-01-01

    Visible light communication (VLC) is an emerging technology in optical wireless communication (OWC) that has attracted worldwide research in recent years. VLC can combine communication and illumination together, which could be applied in many application scenarios such as visible light communication local area networks (VLANs), indoor localization, and intelligent lighting. In recent years, pioneering and significant work have been made in the field of VLC. In this paper, an overview of the recent progress in VLC is presented. We also demonstrate our recent experiment results including bidirectional 100 Mbit/s VLAN or Li-Fi system based on OOK modulation without blue filter. The VLC systems that we proposed are good solutions for high-speed VLC application systems with low-cost and low-complexity. VLC technology shows a bright future due to its inherent advantages, shortage of RF spectra and ever increasing popularity of white LEDs. Project supported by the National High Technology Research and Development Program of China (Nos. 2015AA033303, 2013AA013602, 2013AA013603, 2013AA03A104), the National Natural Science Foundation of China (Nos. 61178051, 61321063, 61335010, 61178048, 61275169), and the National Basic Research Program of China (Nos. 2013CB329205, 2011CBA00608).

  5. A squeezed light source operated under high vacuum

    PubMed Central

    Wade, Andrew R.; Mansell, Georgia L.; Chua, Sheon S. Y.; Ward, Robert L.; Slagmolen, Bram J. J.; Shaddock, Daniel A.; McClelland, David E.

    2015-01-01

    Non-classical squeezed states of light are becoming increasingly important to a range of metrology and other quantum optics applications in cryptography, quantum computation and biophysics. Applications such as improving the sensitivity of advanced gravitational wave detectors and the development of space-based metrology and quantum networks will require robust deployable vacuum-compatible sources. To date non-linear photonics devices operated under high vacuum have been simple single pass systems, testing harmonic generation and the production of classically correlated photon pairs for space-based applications. Here we demonstrate the production under high-vacuum conditions of non-classical squeezed light with an observed 8.6 dB of quantum noise reduction down to 10 Hz. Demonstration of a resonant non-linear optical device, for the generation of squeezed light under vacuum, paves the way to fully exploit the advantages of in-vacuum operations, adapting this technology for deployment into new extreme environments. PMID:26657616

  6. Monolithic LED arrays, next generation smart lighting sources

    NASA Astrophysics Data System (ADS)

    Lagrange, Alexandre; Bono, Hubert; Templier, François

    2016-03-01

    LED have become the main light sources of the future as they open the path for intelligent use of light in time, intensity and color. In many usages, strong energy economy is done by adjusting these properties. The smart lighting has three dimensions, energy efficiency brought by GaN blue emitting LEDs, integration of electronics, sensors, microprocessors in the lighting system and development of new functionalities and services provided by the light. Monolithic LED arrays allow two major innovations, the spatial control of light emission and the adjustment of the electrical properties of the source.

  7. Barium light source method and apparatus

    NASA Technical Reports Server (NTRS)

    Curry, John J. (Inventor); MacDonagh-Dumler, Jeffrey (Inventor); Anderson, Heidi M. (Inventor); Lawler, James E. (Inventor)

    2002-01-01

    Visible light emission is obtained from a plasma containing elemental barium including neutral barium atoms and barium ion species. Neutral barium provides a strong green light emission in the center of the visible spectrum with a highly efficient conversion of electrical energy into visible light. By the selective excitation of barium ionic species, emission of visible light at longer and shorter wavelengths can be obtained simultaneously with the green emission from neutral barium, effectively providing light that is visually perceived as white. A discharge vessel contains the elemental barium and a buffer gas fill therein, and a discharge inducer is utilized to induce a desired discharge temperature and barium vapor pressure therein to produce from the barium vapor a visible light emission. The discharge can be induced utilizing a glow discharge between electrodes in the discharge vessel as well as by inductively or capacitively coupling RF energy into the plasma within the discharge vessel.

  8. Inorganic volumetric light source excited by ultraviolet light

    DOEpatents

    Reed, S.; Walko, R.J.; Ashley, C.S.; Brinker, C.J.

    1994-04-26

    The invention relates to a composition for the volumetric generation of radiation. The composition comprises a porous substrate loaded with a component capable of emitting radiation upon interaction with an exciting radiation. Preferably, the composition is an aerogel substrate loaded with a component, e.g., a phosphor, capable of interacting with exciting radiation of a first energy, e.g., ultraviolet light, to produce radiation of a second energy, e.g., visible light. 4 figures.

  9. Inorganic volumetric light source excited by ultraviolet light

    DOEpatents

    Reed, Scott; Walko, Robert J.; Ashley, Carol S.; Brinker, C. Jeffrey

    1994-01-01

    The invention relates to a composition for the volumetric generation of radiation. The composition comprises a porous substrate loaded with a component capable of emitting radiation upon interaction with an exciting radiation. Preferably, the composition is an aerogel substrate loaded with a component, e.g., a phosphor, capable of interacting with exciting radiation of a first energy, e.g., ultraviolet light, to produce radiation of a second energy, e.g., visible light.

  10. Status and Prospects of Coherent Light Source Developments at UVSOR-II

    SciTech Connect

    Adachi, Masahiro; Katoh, Masahiro; Zen, Heishun; Tanikawa, Takanori; Hosaka, Masahito; Takashima, Yoshifumi; Yamamoto, Naoto; Taira, Yoshitaka

    2010-06-23

    We are developing coherent light sources at the UVSOR-II electron storage ring. We have developed a resonator type free electron laser in the visible to the deep UV range, coherent harmonic generation source in VUV range and coherent synchrotron radiation source in the terahertz range. A new five year plan has been started from FY2008, where a new 4m straight section will be created by moving the beam injection point, a new optical klystron type undulator will be installed and dedicated beam-lines will be constructed. Great advances on the coherent light source developments at the new straight section are expected.

  11. Flexible microstructured organic light sources for automotive applications

    NASA Astrophysics Data System (ADS)

    Melpignano, Patrizia; Sinesi, Sabino; Toaldo, A. Baron; Biondo, Viviana; Muccini, Michele; Zamboni, Roberto; Gale, Michael T.; Westenhofer, Susanne

    2004-09-01

    Organic light-emitting diodes (OLED) are rapidly reaching large-scale marketing figures, driven by attractive features like low cost and fast response, being also suitable for application on flexible substrates. All these aspects enable a wide range of applications such as displays, innovative devices in optoelectronics and novel light sources. Furthermore, the benefits expected from OLEDs based devices, if compared to "classical semiconductors" based devices consist of low production costs, lightweight and geometrical flexibility. Novel OLEDs based light sources fulfilling the above-mentioned requirements, call for a considerable effort both in the production processes and in product innovation. Among the variety of possible applicative OLED applications, we focused our research effort on the Automotive sector. Our envisioned approach enabling control of light distribution from an OLED light source include modeling and patterning of the light source, design and fabrication of suitable micro-optics coupled to the flexible transparent Organic Light Emitting Diode (OLED) substrate.

  12. Advanced Neutron Source radiological design criteria

    SciTech Connect

    Westbrook, J.L.

    1995-08-01

    The operation of the proposed Advanced Neutron Source (ANS) facility will present a variety of radiological protection problems. Because it is desired to design and operate the ANS according to the applicable licensing standards of the Nuclear Regulatory Commission (NRC), it must be demonstrated that the ANS radiological design basis is consistent not only with state and Department of Energy (DOE) and other usual federal regulations, but also, so far as is practicable, with NRC regulations and with recommendations of such organizations as the Institute of Nuclear Power Operations (INPO) and the Electric Power Research Institute (EPRI). Also, the ANS radiological design basis is in general to be consistent with the recommendations of authoritative professional and scientific organizations, specifically the National Council on Radiation Protection and Measurements (NCRP) and the International Commission on Radiological Protection (ICRP). As regards radiological protection, the principal goals of DOE regulations and guidance are to keep occupational doses ALARA [as low as (is) reasonably achievable], given the current state of technology, costs, and operations requirements; to control and monitor contained and released radioactivity during normal operation to keep public doses and releases to the environment ALARA; and to limit doses to workers and the public during accident conditions. Meeting these general design objectives requires that principles of dose reduction and of radioactivity control by employed in the design, operation, modification, and decommissioning of the ANS. The purpose of this document is to provide basic radiological criteria for incorporating these principles into the design of the ANS. Operations, modification, and decommissioning will be covered only as they are affected by design.

  13. X-ray Optics for BES Light Source Facilities

    SciTech Connect

    Mills, Dennis; Padmore, Howard; Lessner, Eliane

    2013-03-27

    potentially revolutionary science involves soft excitations such as magnons and phonons; in general, these are well below the resolution that can be probed by today’s optical systems. The study of these low-energy excitations will only move forward if advances are made in high-resolution gratings for the soft X-ray energy region, and higher-resolution crystal analyzers for the hard X-ray region. In almost all the forefront areas of X-ray science today, the main limitation is our ability to focus, monochromate, and manipulate X-rays at the level required for these advanced measurements. To address these issues, the U.S. Department of Energy (DOE) Office of Basic Energy Sciences (BES) sponsored a workshop, X-ray Optics for BES Light Source Facilities, which was held March 27–29, 2013, near Washington, D.C. The workshop addressed a wide range of technical and organizational issues. Eleven working groups were formed in advance of the meeting and sought over several months to define the most pressing problems and emerging opportunities and to propose the best routes forward for a focused R&D program to solve these problems. The workshop participants identified eight principal research directions (PRDs), as follows: Development of advanced grating lithography and manufacturing for high-energy resolution techniques such as soft X-ray inelastic scattering. Development of higher-precision mirrors for brightness preservation through the use of advanced metrology in manufacturing, improvements in manufacturing techniques, and in mechanical mounting and cooling. Development of higher-accuracy optical metrology that can be used in manufacturing, verification, and testing of optomechanical systems, as well as at wavelength metrology that can be used for quantification of individual optics and alignment and testing of beamlines. Development of an integrated optical modeling and design framework that is designed and maintained specifically for X-ray optics. Development of

  14. HIGH BRIGHTNESS ELECTRON GUNS FOR NEXT-GENERATION LIGHT SOURCES AND ACCELERATORS.

    SciTech Connect

    BLUEM,H.P.; BEN-ZVI,I.; SRINIVASAN-RAO,T.; ET AL.

    2004-07-05

    Next-generation light sources and accelerators are being proposed that set unique requirements for the electron source parameters. No single source is suitable for the diverse applications, which have operating characteristics ranging from high-average-current, quasi-CW, to high-peak-current, single-pulse electron beams. Advanced Energy Systems, in collaboration with our various partners, is developing a variety of electron gun concepts for these important applications.

  15. Optical pumping experiments on next-generation light sources

    NASA Astrophysics Data System (ADS)

    Moon, Stephen J.; Fournier, Kevin B.; Scott, H.; Chung, H.-K.; Lee, R. W.

    2004-11-01

    Laser-based plasma spectroscopic techniques have been used with great success to determine the line shapes of atomic transitions in plasmas, study the population kinetics of atomic systems embedded in plasmas, and look at the redistribution of radiation. However, the possibilities for optical lasers end for plasmas with ne > 1022 cm-3 as light propagation is severely altered by the plasma. The construction of the Tesla Test Facility (TTF) at DESY (Deutsche Elektronen-Synchrotron), a short pulse tunable free electron laser in the vacuum-ultraviolet and soft X-ray regime (VUV FEL), based on the SASE (self amplified spontaneous emission) process, will provide a major advance in the capability for dense plasma-related research. This source will provide 1013 photons in a 200 fs duration pulse that is tunable from ~6 nm to 100 nm. Since an VUV FEL will not have the limitation associated with optical lasers the entire field of high density plasmas kinetics in laser produced plasma will then be available to study with the tunable source. Thus, one will be able to use this and other FEL x-ray sources to pump individual transitions creating enhanced population in the excited states that can be easily monitored. We show two case studies illuminating different aspects of plasma spectroscopy.

  16. Optical Pumping Experiments on Next Generation Light Sources

    SciTech Connect

    Moon, S J; Fournier, K B; Scott, H; Chung, H K; Lee, R W

    2004-07-29

    Laser-based plasma spectroscopic techniques have been used with great success to determine the line shapes of atomic transitions in plasmas, study the population kinetics of atomic systems embedded in plasmas, and look at the redistribution of radiation. However, the possibilities for optical lasers end for plasmas with n{sub e}>10{sup 22}cm{sup -3} as light propagation is severely altered by the plasma. The construction of the Tesla Test Facility(TTF) at DESY(Deutsche Elektronen-Synchrotron), a short pulse tunable free electron laser in the vacuum-ultraviolet and soft X-ray regime (VUV FEL), based on the SASE(self amplified spontaneous emission) process, will provide a major advance in the capability for dense plasma-related research. This source will provide 10{sup 13} photons in a 200 fs duration pulse that is tunable from {approx} 6nm to 100nm. Since an VUV FEL will not have the limitation associated with optical lasers the entire field of high density plasmas kinetics in laser produced plasma will then be available to study with tunable source. Thus, one will be able to use this and other FEL x-ray sources to pump individual transitions creating enhanced population in the excited states that can easily be monitored. We show two case studies illuminating different aspects of plasma spectroscopy.

  17. Recent Advances in Conjugated Polymers for Light Emitting Devices

    PubMed Central

    AlSalhi, Mohamad Saleh; Alam, Javed; Dass, Lawrence Arockiasamy; Raja, Mohan

    2011-01-01

    A recent advance in the field of light emitting polymers has been the discovery of electroluminescent conjugated polymers, that is, kind of fluorescent polymers that emit light when excited by the flow of an electric current. These new generation fluorescent materials may now challenge the domination by inorganic semiconductor materials of the commercial market in light-emitting devices such as light-emitting diodes (LED) and polymer laser devices. This review provides information on unique properties of conjugated polymers and how they have been optimized to generate these properties. The review is organized in three sections focusing on the major advances in light emitting materials, recent literature survey and understanding the desirable properties as well as modern solid state lighting and displays. Recently, developed conjugated polymers are also functioning as roll-up displays for computers and mobile phones, flexible solar panels for power portable equipment as well as organic light emitting diodes in displays, in which television screens, luminous traffic, information signs, and light-emitting wallpaper in homes are also expected to broaden the use of conjugated polymers as light emitting polymers. The purpose of this review paper is to examine conjugated polymers in light emitting diodes (LEDs) in addition to organic solid state laser. Furthermore, since conjugated polymers have been approved as light-emitting organic materials similar to inorganic semiconductors, it is clear to motivate these organic light-emitting devices (OLEDs) and organic lasers for modern lighting in terms of energy saving ability. In addition, future aspects of conjugated polymers in LEDs were also highlighted in this review. PMID:21673938

  18. 21 CFR 352.71 - Light source (solar simulator).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Light source (solar simulator). 352.71 Section 352... Light source (solar simulator). A solar simulator used for determining the SPF of a sunscreen drug... total energy output contributed by nonsolar wavelengths shorter than 290 nanometers; and it has not...

  19. 21 CFR 352.71 - Light source (solar simulator).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Light source (solar simulator). 352.71 Section 352... Light source (solar simulator). A solar simulator used for determining the SPF of a sunscreen drug... total energy output contributed by nonsolar wavelengths shorter than 290 nanometers; and it has not...

  20. 21 CFR 352.71 - Light source (solar simulator).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Light source (solar simulator). 352.71 Section 352... Light source (solar simulator). A solar simulator used for determining the SPF of a sunscreen drug... total energy output contributed by nonsolar wavelengths shorter than 290 nanometers; and it has not...

  1. 21 CFR 352.71 - Light source (solar simulator).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Light source (solar simulator). 352.71 Section 352... Light source (solar simulator). A solar simulator used for determining the SPF of a sunscreen drug... total energy output contributed by nonsolar wavelengths shorter than 290 nanometers; and it has not...

  2. 21 CFR 352.71 - Light source (solar simulator).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Light source (solar simulator). 352.71 Section 352... Light source (solar simulator). A solar simulator used for determining the SPF of a sunscreen drug... total energy output contributed by nonsolar wavelengths shorter than 290 nanometers; and it has not...

  3. Phosphor-Free Solid State Light Sources

    SciTech Connect

    Nause, Jeff E; Ferguson, Ian; Doolittle, Alan

    2007-02-28

    The objective of this work was to demonstrate a light emitting diode that emitted white light without the aid of a phosphor. The device was based on the combination of a nitride LED and a fluorescing ZnO substrate. The early portion of the work focused on the growth of ZnO in undoped and doped form. The doped ZnO was successfully engineered to emit light at specific wavelengths by incorporating various dopants into the crystalline lattice. Thereafter, the focus of the work shifted to the epitaxial growth of nitride structures on ZnO. Initially, the epitaxy was accomplished with molecular beam epitaxy (MBE). Later in the program, metallorganic chemical vapor deposition (MOCVD) was successfully used to grow nitrides on ZnO. By combining the characteristics of the doped ZnO substrate with epitaxially grown nitride LED structures, a phosphor-free white light emitting diode was successfully demonstrated and characterized.

  4. Simple, fast, bright, and stable light sources.

    PubMed

    Tordera, Daniel; Meier, Sebastian; Lenes, Martijn; Costa, Rubén D; Ortí, Enrique; Sarfert, Wiebke; Bolink, Henk J

    2012-02-14

    In this work we show that solution-processed light-emitting electrochemical cells (LECs) based on only an ionic iridium complex and a small amount of ionic liquid exhibit exceptionally good performances when applying a pulsed current: sub-second turn-on times and almost constant high luminances (>600 cd m(-2) ) and power efficiencies over the first 600 h. This demonstrates the potential of LECs for applications in solid-state signage and lighting.

  5. Study on paper moisture measurement method by monochromatic light sources

    NASA Astrophysics Data System (ADS)

    Mo, Changtao; Du, Xin; He, Ping; Zhang, Lili; Li, Nan; Wang, Ming

    2010-10-01

    We design the emission and detection optical paths of three monochromatic infrared light sources with different wavelength. The three light sources are placed according to the different angles, so that the three kinds of monochromatic lights are converged on the same point of the sample. Using the method, we can detect the same point and improve the measurement accuracy. We choose the standard near-infrared monochromatic light source, so that we can save some equipments, such as tungsten- halogen lamp, filtered wheel, collimation focalizer, electric machine, and so on. In particular, we save the cumbersome cooling system, reduce the volume of the instrument greatly and reduce the cost. The three monochromatic light sources are supplied by the same pulse power source, to ensure their synchronous working.

  6. UV emissions from low energy artificial light sources.

    PubMed

    Fenton, Leona; Moseley, Harry

    2014-01-01

    Energy efficient light sources have been introduced across Europe and many other countries world wide. The most common of these is the Compact Fluorescent Lamp (CFL), which has been shown to emit ultraviolet (UV) radiation. Light Emitting Diodes (LEDs) are an alternative technology that has minimal UV emissions. This brief review summarises the different energy efficient light sources available on the market and compares the UV levels and the subsequent effects on the skin of normal individuals and those who suffer from photodermatoses.

  7. Light extraction by Lambertian sources from light emitting diodes

    NASA Astrophysics Data System (ADS)

    Nagel, James R.

    2013-03-01

    Internal back-and-forth propagation of photons within a light emitting diode (LED) will naturally tend towards a Lambertian intensity profile when surface texturing is sufficiently rough. Novel designs in light extraction efficiency (LEE) can therefore benefit by optimizing under this expectation. This paper develops a framework for calculating LEE from a planar LED structure with textured surface features under the assumption of Lambertian intensity within the substrate. The method can estimate the total LEE value when given a substrate width w, an attenuation constant α, and the transmittance function T(θ,Φ) through the top interface. We demonstrate our theory on a pyramidal surface texture over a GaSb substrate at 4.5 μm wavelength by computing the expected LEE as a function of w.

  8. NATIONAL SYNCHROTRON LIGHT SOURCE ACTIVITY REPORT 1998.

    SciTech Connect

    ROTHMAN,E.

    1999-05-01

    thereafter for half of the running time in FY 1998. In combination with the development of narrow gap undulators this mode opens the possibility of new undulators which could produce hard X-rays in the fundamental, perhaps up to 10 keV. On 27 September 1998, a low horizontal emittance lattice became operational at 2.584 GeV. This results in approximately a 50% decrease in the horizontal beam-size on dipole bending magnet beamlines, and somewhat less of a decrease on the insertion device lines. The beam lifetime is not degraded by the low emittance lattice. This represents an important achievement, enhancing for all users the x-ray ring brightness. The reduced horizontal emittance electron beam will produce brighter x-ray beams for all the beamlines, both bending magnets and insertion devices, adding to other recent increases in the X-Ray ring brightness. During FY 1999 users will gain experience of the new running mode and plans are in place to do the same at 2.8GeV during further studies sessions. Independent evidence of the reduced emittance is shown in Figure 2. This is a pinhole camera scan showing the X-ray beam profile, obtained on the diagnostic beamline X28. Finally, work has begun to update and refine the proposal of the Phase III upgrade endorsed by the Birgeneau panel and BESAC last year. With the whole NSLS facility in teenage years and with many demonstrated enhancements available, the time has come to herald in the next stage of life at the Light Source.

  9. Next Generation Accelerator-Based Light Sources

    SciTech Connect

    Gwyn Williams

    2005-06-26

    We discuss the physics which is driving the evolution of new sources for microscopy and spectroscopy. A new generation of sources, called energy recovery linacs or ERL’s, will be described and reviewed with particular emphasis on the examples of imaging and spectroscopic applications enabled by them.

  10. Development of implantable light source for optogenetics

    NASA Astrophysics Data System (ADS)

    Rusakov, Konstantin; Radzewicz, Czesław

    2016-09-01

    The research described here aims at a design and fabrication of a light emitting module for a mobile optogenetic device for animals that are freely moving in the IntelliCage system cages. The device is designed to stimulate selected brain areas of the animal with light. The approach described here is based on a LED chip attached to the tip of a cannula which will be directly implanted into a mouse's brain. The device has been fabricated and tested in a laboratory. In addition, we have observed optogenetic effect on the slice of mice brain tissue in vitro stimulated with our implants.

  11. A new storage-ring light source

    SciTech Connect

    Chao, Alex

    2015-06-01

    A recently proposed technique in storage ring accelerators is applied to provide potential high-power sources of photon radiation. The technique is based on the steady-state microbunching (SSMB) mechanism. As examples of this application, one may consider a high-power DUV photon source for research in atomic and molecular physics or a high-power EUV radiation source for industrial lithography. A less challenging proof-of-principle test to produce IR radiation using an existing storage ring is also considered.

  12. Rapidly pulsed, high intensity, incoherent light source

    NASA Technical Reports Server (NTRS)

    Evans, J. C., Jr.; Brandhorst, H. W., Jr. (Inventor)

    1974-01-01

    A rapid pulsing, high intensity, incoherent light is produced by selectively energizing a plurality of discharge lamps with a triggering circuit. Each lamp is connected to a capacitor, and a power supply is electrically connected to all but one of the capacitors. This last named capacitor is electrically connected to a discharge lamp which is connected to the triggering circuit.

  13. Cathodoluminescent Source of Intense White Light

    NASA Technical Reports Server (NTRS)

    Foster, John E.

    2007-01-01

    The device described exploits cathodoluminescence to generate intense light in the visible and near-infrared regions of the spectrum. In this device, the material to be excited to luminescence is a layer of quartz or alumina powder on an electrically conductive plate exposed to a low-pressure plasma discharge. The plate is electrically biased positively to collect electron current.

  14. An advanced negative hydrogen ion source

    SciTech Connect

    Goncharov, Alexey A. Dobrovolsky, Andrey N.; Goretskii, Victor P.

    2016-02-15

    The results of investigation of emission productivity of negative particles source with cesiated combined discharge are presented. A cylindrical beam of negative hydrogen ions with density about 2 A/cm{sup 2} in low noise mode on source emission aperture is obtained. The total beam current values are up to 200 mA for negative hydrogen ions and up to 1.5 A for all negative particles with high divergence after source. The source has simple design and can produce stable discharge with low level of oscillation.

  15. How advances in light technology have shaped ENT.

    PubMed

    Mozaffari, M; Fishman, J M; Tolley, N S

    2016-02-01

    The development of light technologies, allowing anatomical visualisation of otherwise hidden structures, led to significant advances in ENT in the nineteenth and twentieth centuries. Natural light from the sun, and from candles, was initially harnessed using mirrors. Later, the invention of limelight and electricity preceded the emergence of the modern-day endoscope, which, in tandem with the discovery of coherent fibre-optics in the 1950s, significantly expanded the surgical repertoire available to otolaryngologists. This study aimed to trace the rich history of ENT through the specialty's use of light.

  16. An experiment on the color rendering of different light sources

    NASA Astrophysics Data System (ADS)

    Fumagalli, Simonetta; Bonanomi, Cristian; Rizzi, Alessandro

    2013-02-01

    The color rendering index (CRI) of a light source attempts to measure how much the color appearance of objects is preserved when they are illuminated by the given light source. This problem is of great importance for various industrial and scientific fields, such as lighting architecture, design, ergonomics, etc. Usually a light source is specified through the Correlated Color Temperature or CCT. However two (or more) light sources with the same CCT but different spectral power distribution can exist. Therefore color samples viewed under two light sources with equal CCTs can appear different. Hence, the need for a method to assess the quality of a given illuminant in relation to color. Recently CRI has had a renewed interest because of the new LED-based lighting systems. They usually have a color rendering index rather low, but good preservation of color appearance and a pleasant visual appearance (visual appeal). Various attempts to develop a new color rendering index have been done so far, but still research is working for a better one. This article describes an experiment performed by human observers concerning the appearance preservation of color under some light sources, comparing it with a range of available color rendering indices.

  17. Future Synchrotron Light Sources Based on Ultimate Storage Rings

    SciTech Connect

    Cai, Yunhai; /SLAC

    2012-04-09

    The main purpose of this talk is to describe how far one might push the state of the art in storage ring design. The talk will start with an overview of the latest developments and advances in the design of synchrotron light sources based on the concept of an 'ultimate' storage ring. The review will establish how bright a ring based light source might be, where the frontier of technological challenges are, and what the limits of accelerator physics are. Emphasis will be given to possible improvements in accelerator design and developments in technology toward the goal of achieving an ultimate storage ring. An ultimate storage ring (USR), defined as an electron ring-based light source having an emittance in both transverse planes at the diffraction limit for the range of X-ray wavelengths of interest for a scientific community, would provide very high brightness photons having high transverse coherence that would extend the capabilities of X-ray imaging and probe techniques beyond today's performance. It would be a cost-effective, high-coherence 4th generation light source, competitive with one based on energy recovery linac (ERL) technology, serving a large number of users studying material, chemical, and biological sciences. Furthermore, because of the experience accumulated over many decades of ring operation, it would have the great advantage of stability and reliability. In this paper we consider the design of an USR having 10-pm-rad emittance. It is a tremendous challenge to design a storage ring having such an extremely low emittance, a factor of 100 smaller than those in existing light sources, especially such that it has adequate dynamic aperture and beam lifetime. In many ultra-low emittance designs, the injection acceptances are not large enough for accumulation of the electron beam, necessitating on-axis injection where stored electron bunches are completely replaced with newly injected ones. Recently, starting with the MAX-IV 7-bend achromatic cell, we

  18. A numerical experiment on light pollution from distant sources

    NASA Astrophysics Data System (ADS)

    Kocifaj, M.

    2011-08-01

    To predict the light pollution of the night-time sky realistically over any location or measuring point on the ground presents quite a difficult calculation task. Light pollution of the local atmosphere is caused by stray light, light loss or reflection of artificially illuminated ground objects or surfaces such as streets, advertisement boards or building interiors. Thus it depends on the size, shape, spatial distribution, radiative pattern and spectral characteristics of many neighbouring light sources. The actual state of the atmospheric environment and the orography of the surrounding terrain are also relevant. All of these factors together influence the spectral sky radiance/luminance in a complex manner. Knowledge of the directional behaviour of light pollution is especially important for the correct interpretation of astronomical observations. From a mathematical point of view, the light noise or veil luminance of a specific sky element is given by a superposition of scattered light beams. Theoretical models that simulate light pollution typically take into account all ground-based light sources, thus imposing great requirements on CPU and MEM. As shown in this paper, a contribution of distant sources to the light pollution might be essential under specific conditions of low turbidity and/or Garstang-like radiative patterns. To evaluate the convergence of the theoretical model, numerical experiments are made for different light sources, spectral bands and atmospheric conditions. It is shown that in the worst case the integration limit is approximately 100 km, but it can be significantly shortened for light sources with cosine-like radiative patterns.

  19. Advanced Photon Source research: Volume 1, Number 1, April 1998

    SciTech Connect

    1998-04-01

    The following articles are included in this publication: (1) The Advanced Photon Source: A Brief Overview; (2) MAD Analysis of FHIT at the Structural Biology Center; (3) Advances in High-Energy-Resolution X-ray Scattering at Beamline 3-ID; (4) X-ray Imaging and Microspectroscopy of the Mycorrhyizal Fungus-Plant Symbiosis; (5) Measurement and Control of Particle-beam Trajectories in the Advanced Photon Storage Ring; (6) Beam Acceleration and Storage at the Advanced Photon Source; and (7) Experimental Facilities Operations and Current Status.

  20. Measurement of the speed of light from extraterrestrial sources

    NASA Astrophysics Data System (ADS)

    Wu, Jingshown; Huang, Yen-Ru; Tsao, Hen-Wai; Lee, San-Liang; Chang, Shenq-Tsong; Tsay, Ho-Lin; Young, Hong-Tsu

    2015-09-01

    The conventional measurements of the speed of light were performed before the early twentieth century. Only few used extraterrestrial sources and got the result with large uncertainty. We design a transmitter to modulate the rays from the local infrared light source and the extraterrestrial sources simultaneously into pulses. Both are received by a distant receiver. We have the white light travelling exactly along the path of the starlight pulses for calibration. It is found that the travel times of Aldebaran and Capella pulses are longer than that of Vega pulses. The results indicate that the speeds of starlights are different.

  1. Potential Sources of Polarized Light from a Plant Canopy

    NASA Technical Reports Server (NTRS)

    Vanderbilt, Vern; Daughtry, Craig; Dahlgren, Robert

    2016-01-01

    Field measurements have demonstrated that sunlight polarized during a first surface reflection by shiny leaves dominates the optical polarization of the light reflected by shiny-leafed plant canopies having approximately spherical leaf angle probability density functions ("Leaf Angle Distributions" - LAD). Yet for other canopies - specifically those without shiny leaves and/or spherical LADs - potential sources of optically polarized light may not always be obvious. Here we identify possible sources of polarized light within those other canopies and speculate on the ecologically important information polarization measurements of those sources might contain.

  2. Synchronization System for Next Generation Light Sources

    SciTech Connect

    Zavriyev, Anton

    2014-03-27

    An alternative synchronization technique – one that would allow explicit control of the pulse train including its repetition rate and delay is clearly desired. We propose such a scheme. Our method is based on optical interferometry and permits synchronization of the pulse trains generated by two independent mode-locked lasers. As the next generation x-ray sources will be driven by a clock signal derived from a mode-locked optical source, our technique will provide a way to synchronize x-ray probe with the optical pump pulses.

  3. Gallium Nitride Nanowires and Heterostructures: Toward Color-Tunable and White-Light Sources.

    PubMed

    Kuykendall, Tevye R; Schwartzberg, Adam M; Aloni, Shaul

    2015-10-14

    Gallium-nitride-based light-emitting diodes have enabled the commercialization of efficient solid-state lighting devices. Nonplanar nanomaterial architectures, such as nanowires and nanowire-based heterostructures, have the potential to significantly improve the performance of light-emitting devices through defect reduction, strain relaxation, and increased junction area. In addition, relaxation of internal strain caused by indium incorporation will facilitate pushing the emission wavelength into the red. This could eliminate inefficient phosphor conversion and enable color-tunable emission or white-light emission by combining blue, green, and red sources. Utilizing the waveguiding modes of the individual nanowires will further enhance light emission, and the properties of photonic structures formed by nanowire arrays can be implemented to improve light extraction. Recent advances in synthetic methods leading to better control over GaN and InGaN nanowire synthesis are described along with new concept devices leading to efficient white-light emission.

  4. Phenomenological Modeling of Infrared Sources: Recent Advances

    NASA Technical Reports Server (NTRS)

    Leung, Chun Ming; Kwok, Sun (Editor)

    1993-01-01

    Infrared observations from planned space facilities (e.g., ISO (Infrared Space Observatory), SIRTF (Space Infrared Telescope Facility)) will yield a large and uniform sample of high-quality data from both photometric and spectroscopic measurements. To maximize the scientific returns of these space missions, complementary theoretical studies must be undertaken to interpret these observations. A crucial step in such studies is the construction of phenomenological models in which we parameterize the observed radiation characteristics in terms of the physical source properties. In the last decade, models with increasing degree of physical realism (in terms of grain properties, physical processes, and source geometry) have been constructed for infrared sources. Here we review current capabilities available in the phenomenological modeling of infrared sources and discuss briefly directions for future research in this area.

  5. Vacuum chamber thermal protection for the APS (Advanced Photon Source)

    SciTech Connect

    Kramer, S.L.; Crosbie, E.A.; Kim, S.; Wehrle, R.; Yoon, M.

    1989-01-01

    The addition of undulators and wigglers into synchrotron storage rings created new problems in terms of protecting the integrity of the ring vacuum chamber. If the photon beam from these devices were missteered into striking an inadequately cooled section of the storage ring vacuum chamber, the structural strength might be reduced sufficiently that the vacuum envelope could be penetrated, resulting in long downtime of the storage ring. The new generation of high-energy synchrotron light sources will produce photon beams of such high power density that cooling of the vacuum chamber will not prevent a potential penetration of the vacuum envelope, and other methods of preventing this occurrence will be required. Since active methods will be used to ensure that the beams are delivered to beam lines for users during normal operation, there is a need for passive protection methods during non-routine operation, such as turning on new beam lines, injection, etc., when the active systems may be disabled. In addition, the passive methods could prevent the problem from arising and provide the rapid time response necessary for the highest power beams, a property that might not be easily and reliably provided by active methods during the early operation of these machines. This paper summarizes the results of a task group that studied the problem and outlines passive methods of protection for the Advanced Photon Source (APS). 2 refs., 3 figs., 1 tab.

  6. Pulse-modulated light source for psychometric and vision experiments.

    PubMed

    Scholfield, C N; Murdock, M

    1987-03-01

    Light-emitting diodes (LED) of various colours were used to produce accurately controllable light sources. Variable light intensity was obtained by applying 800-ns current pulses to the LEDs at frequencies 1-1000 kHz using a single potentiometer. These current pulses were generated from an oscillator which was voltage-controlled from a potentiometer and an antilogarithmic amplifier. Its output was gated to produce an optional flicker of 1-100 Hz. The light intensity was indicated by a frequency meter connected to the oscillator. The reading of this was found to linearly indicate light intensity.

  7. Open-source products for a lighting experiment device.

    PubMed

    Gildea, Kevin M; Milburn, Nelda

    2014-12-01

    The capabilities of open-source software and microcontrollers were used to construct a device for controlled lighting experiments. The device was designed to ascertain whether individuals with certain color vision deficiencies were able to discriminate between the red and white lights in fielded systems on the basis of luminous intensity. The device provided the ability to control the timing and duration of light-emitting diode (LED) and incandescent light stimulus presentations, to present the experimental sequence and verbal instructions automatically, to adjust LED and incandescent luminous intensity, and to display LED and incandescent lights with various spectral emissions. The lighting device could easily be adapted for experiments involving flashing or timed presentations of colored lights, or the components could be expanded to study areas such as threshold light perception and visual alerting systems.

  8. Lighting system combining daylight concentrators and an artificial source

    DOEpatents

    Bornstein, Jonathan G.; Friedman, Peter S.

    1985-01-01

    A combined lighting system for a building interior includes a stack of luminescent solar concentrators (LSC), an optical conduit made of preferably optical fibers for transmitting daylight from the LSC stack, a collimating lens set at an angle, a fixture for receiving the daylight at one end and for distributing the daylight as illumination inside the building, an artificial light source at the other end of the fixture for directing artifical light into the fixture for distribution as illumination inside the building, an automatic dimmer/brightener for the artificial light source, and a daylight sensor positioned near to the LSC stack for controlling the automatic dimmer/brightener in response to the daylight sensed. The system also has a reflector positioned behind the artificial light source and a fan for exhausting heated air out of the fixture during summer and for forcing heated air into the fixture for passage into the building interior during winter.

  9. Interference of light from independent sources

    SciTech Connect

    Pegg, David T.

    2006-12-15

    We extend and generalize previous work on the interference of light from independent cavities that began with the suggestion of Pfleegor and Mandel [Phys. Rev. 159, 1084 (1967)] that their observed interference of laser beams should not be associated too closely with particular states of the beams but more with the detection process itself. In particular we examine how the detection of interference induces a nonrandom-phase difference between internal cavity states with initial random phases for a much broader range of such states than has previously been considered. We find that a subsequent interference measurement should give results consistent with the induced phase difference. The inclusion of more cavities in the interference measurements enables the construction in principle of a laboratory in the sense used by Aharonov and Susskind, made up of cavity fields that can serve as frames of phase reference. We also show reasonably simply how intrinsic phase coherence of a beam of light leaking from a single cavity arises for any internal cavity state, even a photon number state. Although the work presented here may have some implications for the current controversy over whether or not a typical laboratory laser produces a coherent state, it is not the purpose of this paper to enter this controversy; rather it is to examine the interesting quantum physics that arises for cavities with more general internal states.

  10. Advanced UV Source for Biological Agent Destruction

    DTIC Science & Technology

    2006-01-01

    of wavelength. The action spectra for killing of E . coli and S. aureus are shown in Figure 2.2-2. These action spectra, (Gates, F. L. “A Study of...Figure 2.2-1. DNA Damage Mechanisms. Ultraviolet light of the proper wavelength has long been known to produce strong antimicrobial effects. The...The wavelength range from 190 to 300 nm is called far-ultraviolet radiation. This range is also called UVC , and

  11. Large area, surface discharge pumped, vacuum ultraviolet light source

    DOEpatents

    Sze, Robert C.; Quigley, Gerard P.

    1996-01-01

    Large area, surface discharge pumped, vacuum ultraviolet (VUV) light source. A contamination-free VUV light source having a 225 cm.sup.2 emission area in the 240-340 nm region of the electromagnetic spectrum with an average output power in this band of about 2 J/cm.sup.2 at a wall-plug efficiency of approximately 5% is described. Only ceramics and metal parts are employed in this surface discharge source. Because of the contamination-free, high photon energy and flux, and short pulse characteristics of the source, it is suitable for semiconductor and flat panel display material processing.

  12. Large area, surface discharge pumped, vacuum ultraviolet light source

    DOEpatents

    Sze, R.C.; Quigley, G.P.

    1996-12-17

    Large area, surface discharge pumped, vacuum ultraviolet (VUV) light source is disclosed. A contamination-free VUV light source having a 225 cm{sup 2} emission area in the 240-340 nm region of the electromagnetic spectrum with an average output power in this band of about 2 J/cm{sup 2} at a wall-plug efficiency of approximately 5% is described. Only ceramics and metal parts are employed in this surface discharge source. Because of the contamination-free, high photon energy and flux, and short pulse characteristics of the source, it is suitable for semiconductor and flat panel display material processing. 3 figs.

  13. Interferometer combines laser light source and digital counting system

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Measurement of small linear displacements in digital readouts with extreme accuracy and sensitivity is achieved by an interferometer. The instrument combines a digital electro-optical fringe-counting system and a laser light source.

  14. Proposed neutron activation analysis facilities in the Advanced Neutron Source

    SciTech Connect

    Robinson, L.; Dyer, F.F.; Emery, J.F.

    1990-01-01

    A number of analytical chemistry experimental facilities are being proposed for the Advanced Neutron Source. Experimental capabilities will include gamma-ray analysis and neutron depth profiling. This paper describes the various systems proposed and some of their important characteristics.

  15. Performance of single mechanoluminescent particle as ubiquitous light source.

    PubMed

    Terasaki, Nao; Xu, Chao-Nan

    2014-08-01

    In this study, we have investigated mechanoluminescent (ML) performance of single ML particle as ubiquitous light source. When using high-speed CCD camera with image intensifier and microscopic equipment, mechanoluminescence from single particle was observed. As to the quantitative ML evaluation of the single ML particle was carried out using photomultiplier, and successfully estimated the performance of the single ML particle as an intensity controllable light source in nW order.

  16. Modification of light sources for appropriate biological action

    NASA Astrophysics Data System (ADS)

    Kozakov, R.; Schöpp, H.; Franke, St.; Stoll, C.; Kunz, D.

    2010-06-01

    The impact of the non-visual action of light on the design of novel light sources is discussed. Therefore possible modifications of lamps dealing with spectral tailoring and their action on melatonin suppression in usual life situations are investigated. The results of melatonin suppression by plasma lamps are presented. It is shown that even short-time exposure to usual light levels in working areas has an influence on the melatonin onset.

  17. Passivation of quartz for halogen-containing light sources

    DOEpatents

    Falkenstein, Zoran

    1999-01-01

    Lifetime of halogen containing VUV, UV, visible or IR light sources can be extended by passivating the quartz or glass gas containers with halogens prior to filling the quartz with the halogen and rare gas mixtures used to produce the light.

  18. Hyperspectral microscopy to identify foodborne bacteria with optimum lighting source

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hyperspectral microscopy is an emerging technology for rapid detection of foodborne pathogenic bacteria. Since scattering spectral signatures from hyperspectral microscopic images (HMI) vary with lighting sources, it is important to select optimal lights. The objective of this study is to compare t...

  19. Advanced RF power sources for linacs

    SciTech Connect

    Wilson, P.B.

    1996-10-01

    In order to maintain a reasonable over-all length at high center-of-mass energy, the main linac of an electron-positron linear collider must operate at a high accelerating gradient. For copper (non-superconducting) accelerator structures, this implies a high peak power per unit length and a high peak power per RF source, assuming a limited number of discrete sources are used. To provide this power, a number of devices are currently under active development or conceptual consideration: conventional klystrons with multi-cavity output structures, gyroklystrons, magnicons, sheet-beam klystrons, multiple-beam klystrons and amplifiers based on the FEL principle. To enhance the peak power produced by an rf source, the SLED rf pulse compression scheme is currently in use on existing linacs, and new compression methods that produce a flatter output pulse are being considered for future linear colliders. This paper covers the present status and future outlook for the more important rf power sources and pulse compression systems. It should be noted that high gradient electron linacs have applications in addition to high-energy linear colliders; they can, for example, serve as compact injectors for FEL`s and storage rings.

  20. Expert Assessment of Advanced Power Sources

    DTIC Science & Technology

    2007-07-01

    attracting attention worldwide. A South African firm, Pebble Bed Modular Reactor ( PBMR ) Pty, is apparently constructing a demonstration plant near Cape...Encapsulated Nuclear Heat-Source (ENHS), 50 MWe, from UC Berkeley, U.S.; and NEREUS, 8 MWe, reactor from the Netherlands, similar to the PBMR . Several

  1. Compact synchrotron light source of the HSRC.

    PubMed

    Yoshida, K; Takayama, T; Hori, T

    1998-05-01

    A 700 MeV synchrotron radiation source optimized in order to be incorporated in the university laboratory is under commissioning at Hiroshima University. The storage ring is of a racetrack type with two long straight sections for installing undulators. The bending field is as strong as 2.7 T, produced by normal-conducting magnet technology, and delivers synchrotron radiation with a critical wavelength of 1.42 nm. The strong magnetic field also enables a low-energy injection scheme to be employed owing to the fast radiation damping. A 150 MeV microtron has been adopted as the injector.

  2. Novel interfaces for light directed neuronal stimulation: advances and challenges

    PubMed Central

    Bareket-Keren, Lilach; Hanein, Yael

    2014-01-01

    Light activation of neurons is a growing field with applications ranging from basic investigation of neuronal systems to the development of new therapeutic methods such as artificial retina. Many recent studies currently explore novel methods for optical stimulation with temporal and spatial precision. Novel materials in particular provide an opportunity to enhance contemporary approaches. Here we review recent advances towards light directed interfaces for neuronal stimulation, focusing on state-of-the-art nanoengineered devices. In particular, we highlight challenges and prospects towards improved retinal prostheses. PMID:24872704

  3. Novel interfaces for light directed neuronal stimulation: advances and challenges.

    PubMed

    Bareket-Keren, Lilach; Hanein, Yael

    2014-01-01

    Light activation of neurons is a growing field with applications ranging from basic investigation of neuronal systems to the development of new therapeutic methods such as artificial retina. Many recent studies currently explore novel methods for optical stimulation with temporal and spatial precision. Novel materials in particular provide an opportunity to enhance contemporary approaches. Here we review recent advances towards light directed interfaces for neuronal stimulation, focusing on state-of-the-art nanoengineered devices. In particular, we highlight challenges and prospects towards improved retinal prostheses.

  4. High Energy Density Science at the Linac Coherent Light Source

    SciTech Connect

    Lee, R W

    2007-10-19

    High energy density science (HEDS), as a discipline that has developed in the United States from National Nuclear Security Agency (NNSA)-sponsored laboratory research programs, is, and will remain, a major component of the NNSA science and technology strategy. Its scientific borders are not restricted to NNSA. 'Frontiers in High Energy Density Physics: The X-Games of Contemporary Science' identified numerous exciting scientific opportunities in this field, while pointing to the need for a overarching interagency plan for its evolution. Meanwhile, construction of the first x-ray free-electron laser, the Office-of-Science-funded Linear Coherent Light Source-LCLS: the world's first free electron x-ray laser, with 100-fsec time resolution, tunable x-ray energies, a high rep rate, and a 10 order-of-magnitude increase in brightness over any other x-ray source--led to the realization that the scientific needs of NNSA and the broader scientific community could be well served by an LCLS HEDS endstation employing both short-pulse and high-energy optical lasers. Development of this concept has been well received in the community. NNSA requested a workshop on the applicability of LCLS to its needs. 'High Energy Density Science at the LCLS: NNSA Defense Programs Mission Need' was held in December 2006. The workshop provided strong support for the relevance of the endstation to NNSA strategic requirements. The range of science that was addressed covered a wide swath of the vast HEDS phase space. The unique possibilities provided by the LCLS in areas of intense interest to NNSA Defense Programs were discussed. The areas of focus included warm dense matter and equations of state, hot dense matter, and behavior of high-pressure materials under conditions of high strain-rate and extreme dynamic loading. Development of new and advanced diagnostic techniques was also addressed. This report lays out the relevant science, as brief summaries (Ch. II), expanded descriptions (Ch. V), and a

  5. Dielectric Wakefield Accelerator to drive the future FEL Light Source.

    SciTech Connect

    Jing, C.; Power, J.; Zholents, A. )

    2011-04-20

    X-ray free-electron lasers (FELs) are expensive instruments and a large part of the cost of the entire facility is driven by the accelerator. Using a high-energy gain dielectric wake-field accelerator (DWA) instead of the conventional accelerator may provide a significant cost saving and reduction of the facility size. In this article, we investigate using a collinear dielectric wakefield accelerator to provide a high repetition rate, high current, high energy beam to drive a future FEL x-ray light source. As an initial case study, a {approx}100 MV/m loaded gradient, 850 GHz quartz dielectric based 2-stage, wakefield accelerator is proposed to generate a main electron beam of 8 GeV, 50 pC/bunch, {approx}1.2 kA of peak current, 10 x 10 kHz (10 beamlines) in just 100 meters with the fill factor and beam loading considered. This scheme provides 10 parallel main beams with one 100 kHz drive beam. A drive-to-main beam efficiency {approx}38.5% can be achieved with an advanced transformer ratio enhancement technique. rf power dissipation in the structure is only 5 W/cm{sup 2} in the high repetition rate, high gradient operation mode, which is in the range of advanced water cooling capability. Details of study presented in the article include the overall layout, the transform ratio enhancement scheme used to increase the drive to main beam efficiency, main wakefield linac design, cooling of the structure, etc.

  6. National Synchrotron Light Source annual report 1991

    SciTech Connect

    Hulbert, S.L.; Lazarz, N.M.

    1992-04-01

    This report discusses the following research conducted at NSLS: atomic and molecular science; energy dispersive diffraction; lithography, microscopy and tomography; nuclear physics; UV photoemission and surface science; x-ray absorption spectroscopy; x-ray scattering and crystallography; x-ray topography; workshop on surface structure; workshop on electronic and chemical phenomena at surfaces; workshop on imaging; UV FEL machine reviews; VUV machine operations; VUV beamline operations; VUV storage ring parameters; x-ray machine operations; x-ray beamline operations; x-ray storage ring parameters; superconducting x-ray lithography source; SXLS storage ring parameters; the accelerator test facility; proposed UV-FEL user facility at the NSLS; global orbit feedback systems; and NSLS computer system.

  7. Electrically driven and electrically tunable quantum light sources

    NASA Astrophysics Data System (ADS)

    Lee, J. P.; Murray, E.; Bennett, A. J.; Ellis, D. J. P.; Dangel, C.; Farrer, I.; Spencer, P.; Ritchie, D. A.; Shields, A. J.

    2017-02-01

    Compact and electrically controllable on-chip sources of indistinguishable photons are desirable for the development of integrated quantum technologies. We demonstrate that two quantum dot light emitting diodes (LEDs) in close proximity on a single chip can function as a tunable, all-electric quantum light source. Light emitted by an electrically excited driving LED is used to excite quantum dots in the neighbouring diode. The wavelength of the quantum dot emission from the neighbouring driven diode is tuned via the quantum confined Stark effect. We also show that we can electrically tune the fine structure splitting.

  8. Handling high data rate detectors at Diamond Light Source

    NASA Astrophysics Data System (ADS)

    Pedersen, U. K.; Rees, N.; Basham, M.; Ferner, F. J. K.

    2013-03-01

    An increasing number of area detectors, in use at Diamond Light Source, produce high rates of data. In order to capture, store and process this data High Performance Computing (HPC) systems have been implemented. This paper will present the architecture and usage for handling high rate data: detector data capture, large volume storage and parallel processing. The EPICS area Detector frame work has been adopted to abstract the detectors for common tasks including live processing, file format and storage. The chosen data format is HDF5 which provides multidimensional data storage and NeXuS compatibility. The storage system and related computing infrastructure include: a centralised Lustre based parallel file system, a dedicated network and a HPC cluster. A well defined roadmap is in place for the evolution of this to meet demand as the requirements and technology advances. For processing the science data the HPC cluster allow efficient parallel computing, on a mixture of ×86 and GPU processing units. The nature of the Lustre storage system in combination with the parallel HDF5 library allow efficient disk I/O during computation jobs. Software developments, which include utilising optimised parallel file reading for a variety of post processing techniques, are being developed in collaboration as part of the Pan-Data EU Project (www.pan-data.eu). These are particularly applicable to tomographic reconstruction and processing of non crystalline diffraction data.

  9. A multi-source portable light emitting diode spectrofluorometer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A portable luminescence spectrofluorometer weighing only 1.5 kg that uses multiple light emitting diodes (LEDs) as excitation sources was developed and evaluated. Excitation using a sequence of seven individual broad-band LED emission sources enabled the generation of excitation-emission spectra usi...

  10. Conversion degrees of resin composites using different light sources

    PubMed Central

    Ozturk, Bora; Cobanoglu, Nevin; Cetin, Ali Rıza; Gunduz, Beniz

    2013-01-01

    Objective: The objective of this study was to compare the conversion degree of six different composite materials (Filtek Z 250, Filtek P60, Spectrum TPH, Pertac II, Clearfil AP-X, and Clearfil Photo Posterior) using three different light sources (blue light-emitting diode [LED], plasma arc curing [PAC], and conventional halogen lamp [QTH]). Methods: Composites were placed in a 2 mm thick and 5 mm diameter Teflon molds and light cured from the top using three methods: LED for 40 s, PAC for 10 s, and QTH for 40 s. A Fourier Transform Infrared Spectroscopy (FTIR) was used to evaluate the degree of conversion (DC) (n=5). The results were analyzed with two-way analysis of variance and Tukey HSD test. Results: DC was significantly influenced by two variables, light source and composite (P<.05). QTH revealed significantly higher DC values than LED (P<.05). However, there were no significant differences between DC values of QTH and PAC or between DC values of LED and PAC (P>.05). The highest DC was observed in the Z 250 composite specimens following photopolymerization with QTH (70%). The lowest DC was observed in Clearfil Photo Posterior composite specimens following photo-polymerization with LED (43%). Conclusions: The DC was found to be changing according to both light sources and composite materials used. Conventional light halogen (QTH) from light sources and Filtek Z 250 and Filtek P 60 among composite materials showed the most DC performance. PMID:23407765

  11. Demonstration of the light source color on a photograph

    NASA Astrophysics Data System (ADS)

    Yamauchi, Rumi; Ikeda, Mitsuo; Shinoda, Hiroyuki

    2002-06-01

    We don't normally perceive the light source color in a night scene photograph even at the spot of a shining lamp, although of course we do perceive the color if we are in the corresponding real world. This different experience can be nicely explained by the concept of the recognized visual space of illumination, RVSI. We see the light source color for a shining lamp in a real world because its luminance is too high to be included within the RVSI constructed for the world. On the contrary, the luminance of the shining lamp in the photograph never goes beyond that of N10 in Munsell Value and it is easily included within the RVSI constructed for the space where the photograph is observed. The spot should appear a mere white, not a light source color. We proposed in the present paper a new method to perceive the light source color in a printed photograph. A subject used a dimension-up goggle to input only the photograph into his/her monocular eye so that he/she can perceive a 3D scene in it. The RVSI of a small brightness size was made for the scene by employing a night scene photograph and a spot in the scene was perceived as the light source color when the area had lightness 8.1 or larger in Munsell Value.

  12. Cell structure imaging with bright and homogeneous nanometric light source.

    PubMed

    Fukuta, Masahiro; Ono, Atsushi; Nawa, Yasunori; Inami, Wataru; Shen, Lin; Kawata, Yoshimasa; Terekawa, Susumu

    2017-04-01

    Label-free optical nano-imaging of dendritic structures and intracellular granules in biological cells is demonstrated using a bright and homogeneous nanometric light source. The optical nanometric light source is excited using a focused electron beam. A zinc oxide (ZnO) luminescent thin film was fabricated by atomic layer deposition (ALD) to produce the nanoscale light source. The ZnO film formed by ALD emitted the bright, homogeneous light, unlike that deposited by another method. The dendritic structures of label-free macrophage receptor with collagenous structure-expressing CHO cells were clearly visualized below the diffraction limit. The inner fiber structure was observed with 120 nm spatial resolution. Because the bright homogeneous emission from the ZnO film suppresses the background noise, the signal-to-noise ratio (SNR) for the imaging results was greater than 10. The ALD method helps achieve an electron beam excitation assisted microscope with high spatial resolution and high SNR.

  13. Environment assisted degradation mechanisms in advanced light metals

    NASA Technical Reports Server (NTRS)

    Gangloff, R. P.; Stoner, G. E.; Swanson, R. E.

    1989-01-01

    A multifaceted research program on the performance of advanced light metallic alloys in aggressive aerospace environments, and associated environmental failure mechanisms was initiated. The general goal is to characterize alloy behavior quantitatively and to develop predictive mechanisms for environmental failure modes. Successes in this regard will provide the basis for metallurgical optimization of alloy performance, for chemical control of aggressive environments, and for engineering life prediction with damage tolerance and long term reliability.

  14. Status of the MAX IV Light Source Project

    SciTech Connect

    Wallen, Erik; Eriksson, Mikael; Berglund, Magnus; Malmgren, Lars; Lindgren, Lars-Johan; Tarawneh, Hamed; Brandin, Mathias; Werin, Sverker; Thorin, Sara; Sjoestroem, Magnus; Svensson, Haakan; Kumbaro, Dionis; Hansen, Tue

    2007-01-19

    The MAX IV light source project is presented. The MAX IV light source will consist of three low emittance storage rings and a 3 GeV injector linac. The three storage rings will be operated at 700 MeV, 1.5 GeV, and 3.0 GeV, which make it possible to cover a large spectral range from IR to hard X-rays with high brilliance undulator radiation from insertion devices optimised for each storage ring. The preparation of the injector linac to serve as a short pulse source and the major sub-systems of the facility are also presented.

  15. Fifth-Generation Free-Electron Laser Light Sources

    SciTech Connect

    Pellegrini, Claudio

    2011-03-02

    During the past few years, the Linac Coherent Light Source (LCLS) and the Free-Electron Laser in Hamburg (FLASH) have demonstrated the outstanding capability of free-electron lasers (FELs) as sources of coherent radiation in the soft and hard x-ray region. The high intensity, tens of GW, short pulses (few to less than 100 femtoseconds, and the unique transverse coherence properties are opening a new window to study the structure and dynamics of atomic and molecular systems. The LCLS, FLASH, and the other FELs now under construction are only the beginning of the development of these light sources. The next generations will reach new levels of performance: terawatt, atto-second, ultra-small line-width, high repetition rate, full longitudinal and transverse coherence. These future developments and the R&D needed to successfully build and operate the next generation of FEL light sources will be discussed.

  16. Recent advances in the spin Hall effect of light.

    PubMed

    Ling, Xiaohui; Zhou, Xinxing; Huang, Kun; Liu, Yachao; Qiu, Cheng-Wei; Luo, Hailu; Wen, Shuangchun

    2017-03-30

    The spin Hall effect (SHE) of light, as an analogue of the SHE in electronic systems, is a promising candidate for investigating the SHE in semiconductor spintronics/valleytronics, high-energy physics and condensed matter physics, owing to their similar topological nature in the spin-orbit interaction. The SHE of light exhibits unique potential for exploring the physical properties of nanostructures, such as determining the optical thickness, and the material properties of metallic and magnetic thin films and even atomically thin two-dimensional materials. More importantly, it opens a possible pathway for controlling the spin states of photons and developing next-generation photonic spin Hall devices as a fundamental constituent of the emerging spinoptics. In this review, based on the viewpoint of the geometric phase gradient, we give a detailed presentation of the recent advances in the SHE of light and its applications in precision metrology and future spin-based photonics.

  17. Advanced Neutron Source (ANS) Project Progress report, FY 1991

    SciTech Connect

    Campbell, J.H. ); Selby, D.L.; Harrington, R.M. ); Thompson, P.B. . Engineering Division)

    1992-01-01

    This report discusses the following about the Advanced Neutron Source: Project Management; Research and Development; Fuel Development; Corrosion Loop Tests and Analyses; Thermal-Hydraulic Loop Tests; Reactor Control and Shutdown Concepts; Critical and Subcritical Experiments; Material Data, Structural Tests, and Analysis; Cold-Source Development; Beam Tube, Guide, and Instrument Development; Hot-Source Development; Neutron Transport and Shielding; I C Research and Development; Design; and Safety.

  18. Advanced Neutron Source (ANS) Project Progress report, FY 1991

    SciTech Connect

    Campbell, J.H.; Selby, D.L.; Harrington, R.M.; Thompson, P.B.

    1992-01-01

    This report discusses the following about the Advanced Neutron Source: Project Management; Research and Development; Fuel Development; Corrosion Loop Tests and Analyses; Thermal-Hydraulic Loop Tests; Reactor Control and Shutdown Concepts; Critical and Subcritical Experiments; Material Data, Structural Tests, and Analysis; Cold-Source Development; Beam Tube, Guide, and Instrument Development; Hot-Source Development; Neutron Transport and Shielding; I & C Research and Development; Design; and Safety.

  19. Advanced High Brilliance X-Ray Source

    NASA Technical Reports Server (NTRS)

    Gibson, Walter M.

    1998-01-01

    The possibility to dramatically increase the efficiency of laboratory based protein structure measurements through the use of polycapillary X-ray optics was investigated. This project initiated April 1, 1993 and concluded December 31, 1996 (including a no cost extension from June 31, 1996). This is a final report of the project. The basis for the project is the ability to collect X-rays from divergent electron bombardment laboratory X-ray sources and redirect them into quasiparallel or convergent (focused) beams. For example, a 0.1 radian (approx. 6 deg) portion of a divergent beam collected by a polycapillary collimator and transformed into a quasiparallel beam of 3 millradian (0.2 deg) could give a gain of 6(exp 2)/0.2(exp 2) x T for the intensity of a diffracted beam from a crystal with a 0.2 deg diffraction width. T is the transmission efficiency of the polycapillary diffraction optic, and for T=0.5, the gain would be 36/0.04 x O.5=45. In practice, the effective collection angle will depend on the source spot size, the input focal length of the optic (usually limited by the source spot-to-window distance on the x-ray tube) and the size of the crystal relative to the output diameter of the optic. The transmission efficiency, T, depends on the characteristics (fractional open area, surface roughness, shape and channel diameter) of the polycapillary optic and is typically in the range 0.2-0.4. These effects could substantially reduce the expected efficiency gain. During the course of this study, the possibility to use a weakly focused beam (0.5 deg convergence) was suggested which could give an additional 10-20 X efficiency gain for small samples . Weakly focused beams from double focusing mirrors are frequently used for macromolecular crystallography studies. Furthermore the crystals are typically oscillated by as much as 2 deg during each X-ray exposure in order to increase the reciprocal space (number of crystal planes) sampled and use of a slightly convergent

  20. LED-based endoscopic light source for spectral imaging

    NASA Astrophysics Data System (ADS)

    Browning, Craig M.; Mayes, Samuel; Favreau, Peter; Rich, Thomas C.; Leavesley, Silas J.

    2016-03-01

    Colorectal cancer is the United States 3rd leading cancer in death rates.1 The current screening for colorectal cancer is an endoscopic procedure using white light endoscopy (WLE). There are multiple new methods testing to replace WLE, for example narrow band imaging and autofluorescence imaging.2 However, these methods do not meet the need for a higher specificity or sensitivity. The goal for this project is to modify the presently used endoscope light source to house 16 narrow wavelength LEDs for spectral imaging in real time while increasing sensitivity and specificity. The process to do such was to take an Olympus CLK-4 light source, replace the light and electronics with 16 LEDs and new circuitry. This allows control of the power and intensity of the LEDs. This required a larger enclosure to house a bracket system for the solid light guide (lightpipe), three new circuit boards, a power source and National Instruments hardware/software for computer control. The results were a successfully designed retrofit with all the new features. The LED testing resulted in the ability to control each wavelength's intensity. The measured intensity over the voltage range will provide the information needed to couple the camera for imaging. Overall the project was successful; the modifications to the light source added the controllable LEDs. This brings the research one step closer to the main goal of spectral imaging for early detection of colorectal cancer. Future goals will be to connect the camera and test the imaging process.

  1. Experiments with radioactive samples at the Advanced Photon Source.

    SciTech Connect

    Veluri, V. R.; Justus, A.; Glagola, B.; Rauchas, A.; Vacca, J.

    2000-11-01

    The Advanced Photon Source (APS) at Argonne National Laboratory is a national synchrotron-radiation light source research facility. The 7 GeV electron Storage Ring is currently delivering intense high brilliance x-ray beams to a total of 34 beamlines with over 120 experiment stations to members of the international scientific community to carry out forefront basic and applied research in several scientific disciplines. Researchers come to the APS either as members of Collaborative Access Teams (CATs) or as Independent Investigators (IIs). Collaborative Access Teams comprise large number of investigators from universities, industry, and research laboratories with common research objectives. These teams are responsible for the design, construction, finding, and operation of beamlines. They are the owners of their experimental enclosures (''hutches'') designed and built to meet their specific research needs. Fig. 1 gives a plan view of the location of the Collaborative Access Teams by Sector and Discipline. In the past two years, over 2000 individual experiments were conducted at the APS facility. Of these, about 60 experiments involved the use of radioactive samples, which is less than 3% of the total. However, there is an increase in demand for experiment stations to accommodate the use of radioactive samples in different physical forms embedded in various matrices with activity levels ranging from trace amounts of naturally occurring radionuclides to MBq (mCi) quantities including transuranics. This paper discusses in some detail the steps in the safety review process for experiments involving radioactive samples and how ALARA philosophy is invoked at each step and implemented.

  2. Suboptimal Light Conditions Influence Source-Sink Metabolism during Flowering

    PubMed Central

    Christiaens, Annelies; De Keyser, Ellen; Pauwels, Els; De Riek, Jan; Gobin, Bruno; Van Labeke, Marie-Christine

    2016-01-01

    Reliance on carbohydrates during flower forcing was investigated in one early and one late flowering cultivar of azalea (Rhododendron simsii hybrids). Carbohydrate accumulation, invertase activity, and expression of a purported sucrose synthase gene (RsSUS) was monitored during flower forcing under suboptimal (natural) and optimal (supplemental light) light conditions, after a cold treatment (7°C + dark) to break flower bud dormancy. Post-production sucrose metabolism and flowering quality was also assessed. Glucose and fructose concentrations and invertase activity increased in petals during flowering, while sucrose decreased. In suboptimal light conditions RsSUS expression in leaves increased as compared to optimal light conditions, indicating that plants in suboptimal light conditions have a strong demand for carbohydrates. However, carbohydrates in leaves were markedly lower in suboptimal light conditions compared to optimal light conditions. This resulted in poor flowering of plants in suboptimal light conditions. Post-production flowering relied on the stored leaf carbon, which could be accumulated under optimal light conditions in the greenhouse. These results show that flower opening in azalea relies on carbohydrates imported from leaves and is source-limiting under suboptimal light conditions. PMID:26973689

  3. Phototaxis of Grapholitha molesta (Lepidoptera: Olethreutidae) to Different Light Sources.

    PubMed

    Sun, Y-X; Tian, A; Zhang, X-B; Zhao, Z-G; Zhang, Z-W; Ma, R-Y

    2014-10-01

    The Oriental Fruit Moth Grapholita molesta (Busck) causes substantial damage to stone and pome fruit crops worldwide. Light-based traps offer a potential means for pest monitoring and management. In this study, we tested the preference of G. molesta for the following light sources: monochromatic light produced from light-emitting diodes (LEDs) (red, orange, yellow, green, blue, violet, and white), specific wavelengths of light produced from filters (405, 450, 480, 512, 540, 576, and 610 nm), and polychromatic light produced by different numbers (0, 12, 24, and 36) of green, blue, and violet LEDs. The arrangement of polychromatic lights was based on an orthogonal design matrix of L16 (4(3)). Based on the results of former studies, we further determined the optimal number of green and violet LEDs. The results showed that: 1) G. molesta strongly preferred the green, violet, and blue LEDs; 2) G. molesta significantly preferred light at 405 nm, followed by 540 nm, and showed no phototaxis to 480 nm; 3) for the polychromatic light configuration, violet and green were the factors that determined the preference of G. molesta, and the lamp with 12 violet LEDs captured the most moths; and 4) for the lamps with different light intensities, 36 violet LEDs or 12 green LEDs attracted the most moths, with the former performing better.

  4. Data format standard for sharing light source measurements

    NASA Astrophysics Data System (ADS)

    Gregory, G. Groot; Ashdown, Ian; Brandenburg, Willi; Chabaud, Dominique; Dross, Oliver; Gangadhara, Sanjay; Garcia, Kevin; Gauvin, Michael; Hansen, Dirk; Haraguchi, Kei; Hasna, Günther; Jiao, Jianzhong; Kelley, Ryan; Koshel, John; Muschaweck, Julius

    2013-09-01

    Optical design requires accurate characterization of light sources for computer aided design (CAD) software. Various methods have been used to model sources, from accurate physical models to measurement of light output. It has become common practice for designers to include measured source data for design simulations. Typically, a measured source will contain rays which sample the output distribution of the source. The ray data must then be exported to various formats suitable for import into optical analysis or design software. Source manufacturers are also making measurements of their products and supplying CAD models along with ray data sets for designers. The increasing availability of data has been beneficial to the design community but has caused a large expansion in storage needs for the source manufacturers since each software program uses a unique format to describe the source distribution. In 2012, the Illuminating Engineering Society (IES) formed a working group to understand the data requirements for ray data and recommend a standard file format. The working group included representatives from software companies supplying the analysis and design tools, source measurement companies providing metrology, source manufacturers creating the data and users from the design community. Within one year the working group proposed a file format which was recently approved by the IES for publication as TM-25. This paper will discuss the process used to define the proposed format, highlight some of the significant decisions leading to the format and list the data to be included in the first version of the standard.

  5. A Multipurpose LED Light Source for Optics Experiments

    NASA Astrophysics Data System (ADS)

    Mak, Se-yuen

    2004-12-01

    The traditional light source for studying lenses and mirrors is either a bare white light bulb, or one encased inside a lamphouse.2, 3 A simple pattern like an arrow, mounted on an optical bench or printed on the window of a lamphouse, serves as the object. Ironically, the image captured on a translucent screen is often the shadow of the pattern with no light falling on it. Although LEDs have been used in commercial display boards for decades, the advantage of using LEDs as a multipurpose light source in the physics laboratory has been overlooked by many physics teachers. In this paper, we remind readers of a few examples of how LEDs can be used to replace the incandescent lamp for geometrical optics, physical optics, and fiber optics experiments.

  6. Tunable light source for use in photoacoustic spectrometers

    DOEpatents

    Bisson, Scott E.; Kulp, Thomas J.; Armstrong, Karla M.

    2005-12-13

    The present invention provides a photoacoustic spectrometer that is field portable and capable of speciating complex organic molecules in the gas phase. The spectrometer has a tunable light source that has the ability to resolve the fine structure of these molecules over a large wavelength range. The inventive light source includes an optical parametric oscillator (OPO) having combined fine and coarse tuning. By pumping the OPO with the output from a doped-fiber optical amplifier pumped by a diode seed laser, the inventive spectrometer is able to speciate mixtures having parts per billion of organic compounds, with a light source that has a high efficiency and small size, allowing for portability. In an alternative embodiment, the spectrometer is scanned by controlling the laser wavelength, thus resulting in an even more compact and efficient design.

  7. Structural biology research at the National Synchroton Light Source

    SciTech Connect

    1996-05-01

    The world`s foremost facility for scientific research using x-rays and ultraviolet and infrared radiation is operated by the national synchrotron Light Source Department. This year alone, a total of 2200 guest researchers performed experiments at the world`s largest source of synchrotron light. Researchers are trying to define the three- dimensional structures of biological macromolecules to create a map of life, a guide for exploring the biological and chemical interactions of the vast variety of molecules found in living organisms. Studies in structural biology may lead to new insights into how biological systems are formed and nourished, how they survive and grow, how they are damaged and die. This document discusses some the the structural biological research done at the National Synchrotron Light Source.

  8. Collimating lens for light-emitting-diode light source based on non-imaging optics.

    PubMed

    Wang, Guangzhen; Wang, Lili; Li, Fuli; Zhang, Gongjian

    2012-04-10

    A collimating lens for a light-emitting-diode (LED) light source is an essential device widely used in lighting engineering. Lens surfaces are calculated by geometrical optics and nonimaging optics. This design progress does not rely on any software optimization and any complex iterative process. This method can be used for any type of light source not only Lambertian. The theoretical model is based on point source. But the practical LED source has a certain size. So in the simulation, an LED chip whose size is 1 mm*1 mm is used to verify the feasibility of the model. The mean results show that the lenses have a very compact structure and good collimating performance. Efficiency is defined as the ratio of the flux in the illuminated plane to the flux from LED source without considering the lens material transmission. Just investigating the loss in the designed lens surfaces, the two types of lenses have high efficiencies of more than 90% and 99%, respectively. Most lighting area (possessing 80% flux) radii are no more than 5 m when the illuminated plane is 200 m away from the light source.

  9. Sixth users meeting for the Advanced Photon Source: Proceedings

    SciTech Connect

    1994-12-01

    Scientists and engineers from universities, industry, and national laboratories came to review the status of the facility and to look ahead to the types of forefront science that will be possible when the APS is completed. The presentations at the meeting included an overview of the project, advances in synchrotron radiation applications, and technical developments at the APS. The actions taken at the 1994 Business Meeting of the Advanced Photon Source Users Organization are also documented here.

  10. Does the light source affect the repairability of composite resins?

    PubMed

    Karaman, Emel; Gönülol, Nihan

    2014-01-01

    The aim of this study was to examine the effect of the light source on the microshear bond strength of different composite resins repaired with the same substrate. Thirty cylindrical specimens of each composite resin--Filtek Silorane, Filtek Z550 (3M ESPE), Gradia Direct Anterior (GC), and Aelite Posterior (BISCO)--were prepared and light-cured with a QTH light curing unit (LCU). The specimens were aged by thermal cycling and divided into three subgroups according to the light source used--QTH, LED, or PAC (n = 10). They were repaired with the same substrate and a Clearfil Repair Kit (Kuraray). The specimens were light-cured and aged for 1 week in distilled water at 37 °C. The microshear bond strength and failure modes were assessed. There was no significant difference in the microshear bond strength values among the composite resins, except for the Filtek Silorane group that showed significantly lower bond strength values when polymerized with the PAC unit compared to the QTH or LED unit. In conclusion, previously placed dimethacrylate-based composites can be repaired with different light sources; however, if the composite to be repaired is silorane-based, then using a QTH or LED device may be the best option.

  11. LPP-EUV light source for HVM lithography

    NASA Astrophysics Data System (ADS)

    Saito, T.; Ueno, Y.; Yabu, T.; Kurosawa, A.; Nagai, S.; Yanagida, T.; Hori, T.; Kawasuji, Y.; Abe, T.; Kodama, T.; Nakarai, H.; Yamazaki, T.; Mizoguchi, H.

    2017-01-01

    We have been developing a laser produced plasma extremely ultra violet (LPP-EUV) light source for a high volume manufacturing (HVM) semiconductor lithography. It has several unique technologies such as the high power short pulse carbon dioxide (CO2) laser, the short wavelength solid-state pre-pulse laser and the debris mitigation technology with the magnetic field. This paper presents the key technologies for a high power LPP-EUV light source. We also show the latest performance data which is 188W EUV power at intermediate focus (IF) point with 3.7% conversion efficiency (CE) at 100 kHz.

  12. Laser wakefield accelerator based light sources: potential applications and requirements

    SciTech Connect

    Albert, F.; Thomas, A. G.; Mangles, S. P.D.; Banerjee, S.; Corde, S.; Flacco, A.; Litos, M.; Neely, D.; Viera, J.; Najmudin, Z.; Bingham, R.; Joshi, C.; Katsouleas, T.

    2015-01-15

    In this article we review the prospects of laser wakefield accelerators as next generation light sources for applications. This work arose as a result of discussions held at the 2013 Laser Plasma Accelerators Workshop. X-ray phase contrast imaging, X-ray absorption spectroscopy, and nuclear resonance fluorescence are highlighted as potential applications for laser-plasma based light sources. We discuss ongoing and future efforts to improve the properties of radiation from plasma betatron emission and Compton scattering using laser wakefield accelerators for these specific applications.

  13. Applications of laser wakefield accelerator-based light sources

    SciTech Connect

    Albert, Felicie; Thomas, Alec G. R.

    2016-10-01

    Laser-wakefield accelerators (LWFAs) were proposed more than three decades ago, and while they promise to deliver compact, high energy particle accelerators, they will also provide the scientific community with novel light sources. In a LWFA, where an intense laser pulse focused onto a plasma forms an electromagnetic wave in its wake, electrons can be trapped and are now routinely accelerated to GeV energies. From terahertz radiation to gamma-rays, this article reviews light sources from relativistic electrons produced by LWFAs, and discusses their potential applications. Betatron motion, Compton scattering and undulators respectively produce x-rays or gamma-rays by oscillating relativistic electrons in the wakefield behind the laser pulse, a counter-propagating laser field, or a magnetic undulator. Other LWFA-based light sources include bremsstrahlung and terahertz radiation. Here, we first evaluate the performance of each of these light sources, and compare them with more conventional approaches, including radio frequency accelerators or other laser-driven sources. We have then identified applications, which we discuss in details, in a broad range of fields: medical and biological applications, military, defense and industrial applications, and condensed matter and high energy density science.

  14. Applications of laser wakefield accelerator-based light sources

    NASA Astrophysics Data System (ADS)

    Albert, Félicie; Thomas, Alec G. R.

    2016-11-01

    Laser-wakefield accelerators (LWFAs) were proposed more than three decades ago, and while they promise to deliver compact, high energy particle accelerators, they will also provide the scientific community with novel light sources. In a LWFA, where an intense laser pulse focused onto a plasma forms an electromagnetic wave in its wake, electrons can be trapped and are now routinely accelerated to GeV energies. From terahertz radiation to gamma-rays, this article reviews light sources from relativistic electrons produced by LWFAs, and discusses their potential applications. Betatron motion, Compton scattering and undulators respectively produce x-rays or gamma-rays by oscillating relativistic electrons in the wakefield behind the laser pulse, a counter-propagating laser field, or a magnetic undulator. Other LWFA-based light sources include bremsstrahlung and terahertz radiation. We first evaluate the performance of each of these light sources, and compare them with more conventional approaches, including radio frequency accelerators or other laser-driven sources. We have then identified applications, which we discuss in details, in a broad range of fields: medical and biological applications, military, defense and industrial applications, and condensed matter and high energy density science.

  15. Brazilian Synchrotron Light Source: current results and future perspectives

    NASA Astrophysics Data System (ADS)

    Roque da Silva, Antonio Jose

    2013-03-01

    The application of synchrotron radiation in a great variety of fields in general, and condensed matter in particular, has increased steadily worldwide. This, to a large extent, is a result of the availability of the much brighter third-generation light sources, which opened up new experimental techniques. Brazil gave an important contribution to science in Latin America through the development of the necessary technology and the construction of the first synchrotron in the southern hemisphere, still the only one in Latin America. The Laboratório Nacional de Luz Síncrotron - LNLS, operates this installation as an open facility since 1997, having today more than 1300 users yearly. Despite all this success, the current Brazilian light source is a second-generation machine, with relatively low electron energy, high emittance and few straight sections for insertion devices. LNLS is currently engaged in the design and construction of a new, third-generation synchrotron light source. It is being planned to be a state of the art machine, providing tools for cutting edge research that are non existent today in Brazil. In this talk an overview of the status of the current Brazilian light source will be provided, illustrated with some experimental results from users, as well as the future perspectives of the new synchrotron source.

  16. Applications of laser wakefield accelerator-based light sources

    DOE PAGES

    Albert, Felicie; Thomas, Alec G. R.

    2016-10-01

    Laser-wakefield accelerators (LWFAs) were proposed more than three decades ago, and while they promise to deliver compact, high energy particle accelerators, they will also provide the scientific community with novel light sources. In a LWFA, where an intense laser pulse focused onto a plasma forms an electromagnetic wave in its wake, electrons can be trapped and are now routinely accelerated to GeV energies. From terahertz radiation to gamma-rays, this article reviews light sources from relativistic electrons produced by LWFAs, and discusses their potential applications. Betatron motion, Compton scattering and undulators respectively produce x-rays or gamma-rays by oscillating relativistic electrons inmore » the wakefield behind the laser pulse, a counter-propagating laser field, or a magnetic undulator. Other LWFA-based light sources include bremsstrahlung and terahertz radiation. Here, we first evaluate the performance of each of these light sources, and compare them with more conventional approaches, including radio frequency accelerators or other laser-driven sources. We have then identified applications, which we discuss in details, in a broad range of fields: medical and biological applications, military, defense and industrial applications, and condensed matter and high energy density science.« less

  17. The ALS — A third-generation light source

    NASA Astrophysics Data System (ADS)

    Robinson, A. L.; Schlachter, A. S.

    1990-05-01

    The Advanced Light Source, a third-generation national synchrotron-radiation facility now under construction at the Lawrence Berkeley Laboratory, is scheduled to begin serving qualified users across a broad spectrum of research areas in April 1993. Based on a low-emittance electron storage ring optimized to operate at 1.5 GeV, the ALS will have 11 long straight sections available for insertion devices (undulators and wigglers). Undulators will generate high-brightness soft-X-ray and ultraviolet (XUV) radiation; wigglers will extend the spectrum generated into the hard-X-ray region, but at a lower brightness. Up to 48 bending-magnet ports will also be available. Engineering design has begun on a complement of three undulators with periods of 8.0, 5.0, and 3.9 cm. Among them, the photon-energy range from 5.4 eV to 2.5 keV will be covered when the first, third, and fifth undulator harmonics are used. Also being designed is a wiggler with a critical energy of 3.1 keV. Undulator beam lines will be based on high-resolution spherical-grating monochromators. A Call for Proposals has been issued for those who wish to participate in the design, development, commissioning, and operation of the initial complement of the ALS experimental facilities (insertion devices, beam lines, and experimental stations) as members of a participating research team. The deadline for receipt of proposals was August 15, 1989. Proposals are expected to reflect the Letters of Interest received from potential participating research teams (PRTs) during the previous year.

  18. High-speed OCT light sources and systems [Invited

    PubMed Central

    Klein, Thomas; Huber, Robert

    2017-01-01

    Imaging speed is one of the most important parameters that define the performance of optical coherence tomography (OCT) systems. During the last two decades, OCT speed has increased by over three orders of magnitude. New developments in wavelength-swept lasers have repeatedly been crucial for this development. In this review, we discuss the historical evolution and current state of the art of high-speed OCT systems, with focus on wavelength swept light sources and swept source OCT systems. PMID:28270988

  19. Seeing "the Dress" in the Right Light: Perceived Colors and Inferred Light Sources.

    PubMed

    Chetverikov, Andrey; Ivanchei, Ivan

    2016-08-01

    In the well-known "dress" photograph, people either see the dress as blue with black stripes or as white with golden stripes. We suggest that the perception of colors is guided by the scene interpretation and the inferred positions of light sources. We tested this hypothesis in two online studies using color matching to estimate the colors observers see, while controlling for individual differences in gray point bias and color discrimination. Study 1 demonstrates that the interpretation of the dress corresponds to differences in perceived colors. Moreover, people who perceive the dress as blue-and-black are two times more likely to consider the light source as frontal, than those who see the white-and-gold dress. The inferred light sources, in turn, depend on the circadian changes in ambient light. The interpretation of the scene background as a wall or a mirror is consistent with the perceived colors as well. Study 2 shows that matching provides reliable results on differing devices and replicates the findings on scene interpretation and light sources. Additionally, we show that participants' environmental lighting conditions are an important cue for perceiving the dress colors. The exact mechanisms of how environmental lighting and circadian changes influence the perceived colors of the dress deserve further investigation.

  20. High efficiency light source using solid-state emitter and down-conversion material

    DOEpatents

    Narendran, Nadarajah; Gu, Yimin; Freyssinier, Jean Paul

    2010-10-26

    A light emitting apparatus includes a source of light for emitting light; a down conversion material receiving the emitted light, and converting the emitted light into transmitted light and backward transmitted light; and an optic device configured to receive the backward transmitted light and transfer the backward transmitted light outside of the optic device. The source of light is a semiconductor light emitting diode, a laser diode (LD), or a resonant cavity light emitting diode (RCLED). The down conversion material includes one of phosphor or other material for absorbing light in one spectral region and emitting light in another spectral region. The optic device, or lens, includes light transmissive material.

  1. Spectral matching research for light-emitting diode-based neonatal jaundice therapeutic device light source

    NASA Astrophysics Data System (ADS)

    Gan, Ruting; Guo, Zhenning; Lin, Jieben

    2015-09-01

    To decrease the risk of bilirubin encephalopathy and minimize the need for exchange transfusions, we report a novel design for light source of light-emitting diode (LED)-based neonatal jaundice therapeutic device (NJTD). The bilirubin absorption spectrum in vivo was regarded as target. Based on spectral constructing theory, we used commercially available LEDs with different peak wavelengths and full width at half maximum as matching light sources. Simple genetic algorithm was first proposed as the spectral matching method. The required LEDs number at each peak wavelength was calculated, and then, the commercial light source sample model of the device was fabricated to confirm the spectral matching technology. In addition, the corresponding spectrum was measured and the effect was analyzed finally. The results showed that fitted spectrum was very similar to the target spectrum with 98.86 % matching degree, and the actual device model has a spectrum close to the target with 96.02 % matching degree. With higher fitting degree and efficiency, this matching algorithm is very suitable for light source matching technology of LED-based spectral distribution, and bilirubin absorption spectrum in vivo will be auspicious candidate for the target spectrum of new LED-based NJTD light source.

  2. Determining and quantifying specific sources of light alkane

    NASA Astrophysics Data System (ADS)

    Bill, M.; Conrad, M. E.

    2015-12-01

    Determining and quantifying specific sources of emission of methane (an important greenhouse gas) and light alkanes from abandoned gas and oil wells, hydraulic fracturing or associated with CO2 sequestration are a challenge in determining their contribution to the atmospheric greenhouse gas budget or to identify source of groundwater contamination. Here, we review organic biogeochemistry proprieties and isotopic fingerprinting of C1-C5 alkanes to address this problem. For instance, the concentration ratios of CH4 to C2-C5 alkanes can be used to distinguish between thermogenic and microbial generated CH4. Together C and H isotopes of CH4 are used to differentiate bacterial generated sources and thermogenic CH4 and may also identify processes such as alteration and source mixing. Carbon isotope ratios pattern of C1-C5 alkanes highlight sources and oxidation processes in the gas reservoirs. Stable carbon isotope measurements are a viable tool for monitoring the degradation progress of methane and light hydrocarbons. The carbon isotope ratios of the reactants and products are independent of the concentration and only depend on the relative progress of the particular reaction. Oxidation/degradation of light alkanes are typically associated with increasing ð13C values. Isotopic mass balances offer the possibility to independently determine the fractions coming from microbial versus thermogenic and would also permit differentiation of the isotope fractionations associated with degradation. Unlike conventional concentration measurements, this approach is constrained by the different isotopic signatures of various sources and sinks.

  3. Advanced Nuclear Technology: Advanced Light Water Reactors Utility Requirements Document Small Modular Reactors Inclusion Summary

    SciTech Connect

    Loflin, Leonard; McRimmon, Beth

    2014-12-18

    This report summarizes a project by EPRI to include requirements for small modular light water reactors (smLWR) into the EPRI Utility Requirements Document (URD) for Advanced Light Water Reactors. The project was jointly funded by EPRI and the U.S. Department of Energy (DOE). The report covers the scope and content of the URD, the process used to revise the URD to include smLWR requirements, a summary of the major changes to the URD to include smLWR, and how to use the URD as revised to achieve value on new plant projects.

  4. The effect of light-activation sources on tooth bleaching

    PubMed Central

    Baroudi, Kusai; Hassan, Nadia Aly

    2014-01-01

    Vital bleaching is one of the most requested cosmetic dental procedures asked by patients who seek a more pleasing smile. This procedure consists of carbamide or hydrogen peroxide gel applications that can be applied in-office or by the patient (at-home/overnight bleaching system). Some in-office treatments utilise whitening light with the objective of speeding up the whitening process. The objective of this article is to review and summarise the current literature with regard to the effect of light-activation sources on in-office tooth bleaching. A literature search was conducted using Medline, accessed via the National Library of Medicine Pub Med from 2003 to 2013 searching for articles relating to effectiveness of light activation sources on in-office tooth bleaching. This study found conflicting evidence on whether light truly improve tooth whitening. Other factors such as, type of stain, initial tooth colour and subject age which can influence tooth bleaching outcome were discussed. Conclusions: The use of light activator sources with in-office bleaching treatment of vital teeth did not increase the efficacy of bleaching or accelerate the bleaching. PMID:25298598

  5. A mobile light source for carbon/nitrogen cameras

    NASA Astrophysics Data System (ADS)

    Trower, W. P.; Karev, A. I.; Melekhin, V. N.; Shvedunov, V. I.; Sobenin, N. P.

    1995-05-01

    The pulsed light source for carbon/nitrogen cameras developed to image concealed narcotics/explosives is described. This race-track microtron will produce 40 mA pulses of 70 MeV electrons, have minimal size and weight, and maximal ruggedness and reliability, so that it can be transported on a truck.

  6. Enabling instrumentation and technology for 21st century light sources

    SciTech Connect

    Byrd, J.M.; Shea, T.J.; Denes, P.; Siddons, P.; Attwood, D.; Kaertner, F.; Moog, L.; Li, Y.; Sakdinawat, A.; Schlueter, R.

    2010-06-01

    We present the summary from the Accelerator Instrumentation and Technology working group, one of the five working groups that participated in the BES-sponsored Workshop on Accelerator Physics of Future Light Sources held in Gaithersburg, MD September 15-17, 2009. We describe progress and potential in three areas: attosecond instrumentation, photon detectors for user experiments, and insertion devices.

  7. Miniature Incandescent Lamps as Fiber-Optic Light Sources

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret; Collura, Joe; Helvajian, Henry; Pocha, Michael; Meyer, Glenn; McConaghy, Charles F.; Olsen, Barry L.

    2008-01-01

    Miniature incandescent lamps of a special type have been invented to satisfy a need for compact, rapid-response, rugged, broadband, power-efficient, fiber-optic-coupled light sources for diverse purposes that could include calibrating spectrometers, interrogating optical sensors, spot illumination, and spot heating.

  8. Research by industry at the National Synchrotron Light Source

    SciTech Connect

    1995-05-01

    The world`s foremost facility for research using x-rays and ultraviolet and infrared radiation, is operated by the National Synchrotron Light Source dept. This pamphlet described the participating research teams that built most of the beam lines, various techniques for studying materials, treatment of materials, and various industrial research (catalysis, pharmaceuticals, etc.).

  9. Superconducting RF Linac Technology for ERL Light Sources

    SciTech Connect

    Tennant, Chris

    2005-08-01

    Energy Recovering Linacs (ERLs) offer an attractive alternative as drivers for light sources as they combine the desirable characteristics of both storage rings (high efficiency) and linear accelerators (superior beam quality). Using superconducting RF technology allows ERLs to operate more efficiently because of the inherent characteristics of SRF linacs, namely that they are high gradient-low impedance structures and their ability to operate in the long pulse or CW regime. We present an overview of the physics challenges encountered in the design and operation of ERL based light sources with particular emphasis on those issues related to SRF technology. These challenges include maximizing a cavity's Qo to increase cryogenic efficiency, maintaining control of the cavity field in the presence of the highest feasible loaded Q and providing adequate damping of the higher-order modes (HOMs). If not sufficiently damped, dipole HOMs can drive the multipass beam breakup (BBU) instability which ERLs are particularly susceptible to. Another challenge involves efficiently extracting the potentially large amounts of HOM power that are generated when a bunch traverses the SRF cavities and which may extend over a high range of frequencies. We present experimental data from the Jefferson Lab FEL Upgrade, a 10 mA ERL light source presently in operation, aimed at addressing some of these issues. We conclude with an outlook towards the future of ERL based light sources.

  10. The light curve of a transient X-ray source

    NASA Technical Reports Server (NTRS)

    Kaluzienski, L. J.; Holt, S. S.; Boldt, E. A.; Serlemitsos, P. J.; Eadie, G.; Pounds, K. A.; Ricketts, M. J.; Watson, M.

    1975-01-01

    The Ariel-5 satellite has monitored the X-ray light curve of A1524-62 almost continuously from 40 days prior to maximum light until its disappearance below the effective experimental sensitivity. The source exhibited maximum light on Dec. 4, 1974, at a level of 0.9 the apparent magnitude of the Crab Nebula in the energy band 3-6 keV. Although similar to previously reported transient sources with a decay time constant of about 2 months, the source exhibited an extended, variable preflare on-state of about 1 month at a level of greater than 0.1 maximum light. The four bright (greater than 0.2 of the Crab Nebula) transient sources observed during the first half-year of Ariel-5 operation are indicative of a galactic disk distribution, a luminosity at maximum in excess of 10 to the 37-th power ergs/sec, a frequency of occurrence which may be as high as 100/yr, and a median decay time which is less than 1 month.

  11. The Materials Science beamline upgrade at the Swiss Light Source

    PubMed Central

    Willmott, P. R.; Meister, D.; Leake, S. J.; Lange, M.; Bergamaschi, A.; Böge, M.; Calvi, M.; Cancellieri, C.; Casati, N.; Cervellino, A.; Chen, Q.; David, C.; Flechsig, U.; Gozzo, F.; Henrich, B.; Jäggi-Spielmann, S.; Jakob, B.; Kalichava, I.; Karvinen, P.; Krempasky, J.; Lüdeke, A.; Lüscher, R.; Maag, S.; Quitmann, C.; Reinle-Schmitt, M. L.; Schmidt, T.; Schmitt, B.; Streun, A.; Vartiainen, I.; Vitins, M.; Wang, X.; Wullschleger, R.

    2013-01-01

    The Materials Science beamline at the Swiss Light Source has been operational since 2001. In late 2010, the original wiggler source was replaced with a novel insertion device, which allows unprecedented access to high photon energies from an undulator installed in a medium-energy storage ring. In order to best exploit the increased brilliance of this new source, the entire front-end and optics had to be redesigned. In this work, the upgrade of the beamline is described in detail. The tone is didactic, from which it is hoped the reader can adapt the concepts and ideas to his or her needs. PMID:23955029

  12. Advanced radioisotope power source options for Pluto Express

    SciTech Connect

    Underwood, M.L.

    1995-12-31

    In the drive to reduce mass and cost, Pluto Express is investigating using an advanced power conversion technology in a small Radioisotope Power Source (RPS) to deliver the required mission power of 74 W(electric) at end of mission. Until this year the baseline power source under consideration has been a Radioisotope Thermoelectric Generator (RTG). This RTG would be a scaled down GPHS RTG with an inventory of 6 General Purpose Heat Sources (GPHS) and a mass of 17.8 kg. High efficiency, advanced technology conversion options are being examined to lower the power source mass and to reduce the amount of radioisotope needed. Three technologies are being considered as the advanced converter technology: the Alkali Metal Thermal-to-Electric Converter (AMTEC), Thermophotovoltaic (TPV) converters, and Stirling Engines. Conceptual designs for each of these options have been prepared. Each converter would require only 2 GPHSs to provide the mission power and would have a mass of 6.1, 7.2, and 12.4 kg for AMTEC, TPV, and Stirling Engines respectively. This paper reviews the status of each technology and the projected performance of an advanced RPS based on each technology. Based on the projected performance and spacecraft integration issues, Pluto Express would prefer to use the AMTEC based RPS. However, in addition to technical performance, selection of a power technology will be based on many other factors.

  13. Investigations of magnetic overlayers at the Advanced Photon Source

    SciTech Connect

    Tobin, J.G.; Yu, S.-W.; Butterfield, M.T.; Komesu, Takashi; Waddill, G.D.

    2010-08-27

    Magnetic overlayers of Fe and Co have been investigated with x-ray magnetic circular dichroism in x-ray absorption spectroscopy and photoelectron spectroscopy, including spin-resolved photoelectron spectroscopy, at Beamline 4 at the Advanced Photon Source. Particular emphasis was placed upon the interrogation of the 2p levels of the Fe.

  14. Investigations of Magnetic Overlayers at the Advanced Photon Source

    SciTech Connect

    Tobin, J G; Yu, S; Butterfield, M T

    2009-06-26

    Magnetic overlayers of Fe and Co have been investigated with X-ray Magnetic Circular Dichroism in X-ray Absorption Spectroscopy (XMCD-ABS) and Photoelectron Spectroscopy (PES), including Spin-Resolved Photoelectron Spectroscopy (SRPES), at Beamline 4 at the Advanced Photon Source (APS). Particular emphasis was placed upon the interrogation of the 2p levels of the Fe.

  15. Nuclear resonant scattering beamline at the Advanced Photon Source

    SciTech Connect

    Alp, E.E.; Mooney, T.M.; Toellner, T.; Sturhahn, W.

    1993-09-01

    The principal and engineering aspects of a dedicated synchrotron radiation beamline under construction at the Advanced Photon Source for nuclear resonant scattering purposes are explained. The expected performance in terms of isotopes to be studied, flux, and timing properties is discussed.

  16. Improving the Efficiency of Solid State Light Sources

    SciTech Connect

    Joanna McKittrick

    2003-03-31

    This proposal addresses the national need to develop a high efficiency light source for general illumination applications. The goal is to perform research that would lead to the fabrication of a unique solid state, white-emitting light source. This source is based on an InGaN/GaN UV-emitting chip that activates a luminescent material (phosphor) to produce white light. White-light LEDs are commercially available which use UV from a GaN chip to excite a phosphor suspended in epoxy around the chip. Currently, these devices are relatively inefficient. This research will target one technical barrier that presently limits the efficiency of GaN based devices. Improvements in efficiencies will be achieved by improving the internal conversion efficiency of the LED die, by improving the coupling between the die and phosphor(s) to reduce losses at the surfaces, and by selecting phosphors to maximize the emissions from the LEDs in conversion to white light. The UCSD research team proposes for this project to develop new phosphors that have high quantum efficiencies that can be activated by the UV-blue (360-410 nm) light emitted by the GaN device. The main goal for the UCSD team was to develop new phosphor materials with a very specific property: phosphors that could be excited at long UV-wavelengths ({lambda}=350-410 nm). The photoluminescence of these new phosphors must be activated with photons emitted from GaN based dies. The GaN diodes can be designed to emit UV-light in the same range ({lambda}=350-410 nm). A second objective, which is also very important, is to search for alternate methods to fabricate these phosphors with special emphasis in saving energy and time and reduce pollution.

  17. Opportunities for Condensed Matter Research at the Advanced Photon Source

    NASA Astrophysics Data System (ADS)

    Gibson, J. Murray

    2004-03-01

    The Advanced Photon Source is the Western Hemisphere's most brilliant source of x-rays. This 3rd-generation 7-GeV synchrotron source can accomodate 34 insertion device ports, of which 30 are committed, and 24 are currently operating. In Fiscal Year 2002, we had 2767 unique users carry out at least one experiment at the source, of which 35research in materials science or condensed matter physics. Techniques commonly used by condensed matter scientists include single-crystal and powder diffraction, high-pressure studies, inelastic scattering, absorption and fluorescence spectroscopy, magnetic scattering and fluctuation spectroscopy. Access to the Advanced Photon Source can be either as a general user (www.aps.anl.gov) or as a partner user. Proposals from general users are encouraged, and beamtime is granted based on competitive review. Our capacity to accomodate more general users continues to increase. Typically, partner users build specialized equipment which is made available to general users. Many of our sectors have been built and operated by external Collaborative Access Teams, which support general users who enter through the APS centralized system. With the help of partnerships, the APS continues to evolve state-of-the-art beamlines of interest to condensed matter scientists, in areas such as inelastic scattering and nano-imaging. The Advanced Photon Source is closely connected with the new Center for Nanoscale Materials User Facility at Argonne. In this talk I will present notable examples of recent condensed matter physics experiments which utilized the unique capabilities of existing beamlines, and discuss future beamlines at the Advanced Photon Source.

  18. Light extraction by directional sources within optically dense media.

    PubMed

    Nagel, James R

    2012-12-03

    Light extraction efficiency (LEE) from a light-emitting diode is commonly referenced against an isotropic radiator within a dense dielectric medium. However, this description is not necessarily accurate for photonic devices with directional source elements. We therefore derive exact solutions for the LEE of a directive radiating source next to a planar dielectric boundary, accounting for any Fresnel reflections at the interface. These results can be used to validate numerical simulations and to quantify the baseline LEE for different source models. Four variations are explored, including the isotropic radiator, parallel and perpendicular orientations of the Hertzian dipole, and Lambertian scattering. Due to index matching, Fresnel reflections are generally negligible for materials with large escape cones, but reduce LEE by 20 % or more when critical angle is below 25°.

  19. The Consortium for Advanced Simulation of Light Water Reactors

    SciTech Connect

    Ronaldo Szilard; Hongbin Zhang; Doug Kothe; Paul Turinsky

    2011-10-01

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) is a DOE Energy Innovation Hub for modeling and simulation of nuclear reactors. It brings together an exceptionally capable team from national labs, industry and academia that will apply existing modeling and simulation capabilities and develop advanced capabilities to create a usable environment for predictive simulation of light water reactors (LWRs). This environment, designated as the Virtual Environment for Reactor Applications (VERA), will incorporate science-based models, state-of-the-art numerical methods, modern computational science and engineering practices, and uncertainty quantification (UQ) and validation against data from operating pressurized water reactors (PWRs). It will couple state-of-the-art fuel performance, neutronics, thermal-hydraulics (T-H), and structural models with existing tools for systems and safety analysis and will be designed for implementation on both today's leadership-class computers and the advanced architecture platforms now under development by the DOE. CASL focuses on a set of challenge problems such as CRUD induced power shift and localized corrosion, grid-to-rod fretting fuel failures, pellet clad interaction, fuel assembly distortion, etc. that encompass the key phenomena limiting the performance of PWRs. It is expected that much of the capability developed will be applicable to other types of reactors. CASL's mission is to develop and apply modeling and simulation capabilities to address three critical areas of performance for nuclear power plants: (1) reduce capital and operating costs per unit energy by enabling power uprates and plant lifetime extension, (2) reduce nuclear waste volume generated by enabling higher fuel burnup, and (3) enhance nuclear safety by enabling high-fidelity predictive capability for component performance.

  20. Highly Automated Module Production Incorporating Advanced Light Management

    SciTech Connect

    Perelli-Minetti, Michael; Roof, Kyle

    2015-08-11

    The objective was to enable a high volume, cost effective solution for increasing the amount of light captured by PV modules through utilization of an advanced Light Re-directing Film and to follow a phased approach to develop and implement this new technology in order to achieve an expected power gain of up to 12 watts per module. Full size PV modules were manufactured using a new Light Redirecting Film (LRF) material applied to two different areas of PV modules in order to increase the amount of light captured by the modules. One configuration involved applying thin strips of LRF film over the tabbing ribbon on the cells in order to redirect the light that is normally absorbed by the tabbing ribbon to the active areas of the cells. A second configuration involved applying thin strips of LRF film over the white spaces between cells within a module in order to capture some of the light that is normally reflected from the white areas back through the front glass of the modules. Significant power increases of 1.4% (3.9 watts) and 1.0% (3.2 watts), respectively, compared to standard PV modules were measured under standard test conditions. The performance of PV modules with LRF applied to the tabbing ribbon was modeled. The results showed that the power increase provided by LRF depended greatly on the angle of incident light with the optimum performance only occurring when the light was within a narrow range of being perpendicular to the solar module. The modeling showed that most of the performance gain would be lost when the angle of incident light was greater than 28 degrees off axis. This effect made the orientation of modules with LRF applied to tabbing ribbons very important as modules mounted in “portrait” mode were predicted to provide little to no power gain from LRF under real world conditions. Based on these results, modules with LRF on tabbing ribbons would have to be mounted in “landscape” mode to realize a performance advantage. In addition

  1. Effects of laryngoscope handle light source on the light intensity from disposable laryngoscope blades.

    PubMed

    Milne, A D; Brousseau, P A; Brousseau, C A

    2014-12-01

    A bench-top study was performed to assess the effects of different laryngoscope handles on the light intensity delivered from disposable metal or plastic laryngoscope blades. The light intensity from both the handle light sources themselves and the combined handle and laryngoscope blade sets was measured using a custom-designed testing system and light meter. Five samples of each disposable blade type were tested and compared with a standard re-usable stainless steel blade using three different handle/light sources (Vital Signs LED, Heine 2.5 V Xenon and 3.5 V Xenon). The light intensity delivered by the disposable blades ranged from 790 to 3846 lux for the different handle types. Overall, the 3.5 V Heine handle delivered the highest light output (p < 0.007) in comparison with the other handles. For the disposable blades, the overall light output was significantly higher from the plastic than the metal blades (p < 0.001).

  2. Advance in Photosensitizers and Light Delivery for Photodynamic Therapy

    PubMed Central

    Yoon, Il; Li, Jia Zhu

    2013-01-01

    The brief history of photodynamic therapy (PDT) research has been focused on photosensitizers (PSs) and light delivery was introduced recently. The appropriate PSs were developed from the first generation PS Photofrin (QLT) to the second (chlorins or bacteriochlorins derivatives) and third (conjugated PSs on carrier) generations PSs to overcome undesired disadvantages, and to increase selective tumor accumulation and excellent targeting. For the synthesis of new chlorin PSs chlorophyll a is isolated from natural plants or algae, and converted to methyl pheophorbide a (MPa) as an important starting material for further synthesis. MPa has various active functional groups easily modified for the preparation of different kinds of PSs, such as methyl pyropheophorbide a, purpurin-18, purpurinimide, and chlorin e6 derivatives. Combination therapy, such as chemotherapy and photothermal therapy with PDT, is shortly described here. Advanced light delivery system is shown to establish successful clinical applications of PDT. Phtodynamic efficiency of the PSs with light delivery was investigated in vitro and/or in vivo. PMID:23423543

  3. Effects of light sources and visible light-activated titanium dioxide photocatalyst on bleaching.

    PubMed

    Suyama, Yuji; Otsuki, Masayuki; Ogisu, Shinichiro; Kishikawa, Ryuzo; Tagami, Junji; Ikeda, Masaomi; Kurata, Hiroshi; Cho, Takahiro

    2009-11-01

    The objective of this study was to evaluate, using methylene blue (MB), the effects of various light sources on the bleaching action of hydrogen peroxide (H(2)O(2)) with two titanium dioxide (TiO(2)) photocatalysts - an ultraviolet light-activated TiO(2) photocatalyst (UVTiO(2)) versus a visible light-activated TiO(2) photocatalyst (VL-TiO(2)). Five experimental solutions (VL-TiO(2)+H(2)O(2), UV-TiO(2)+H(2)O(2), H(2)O(2), VL-TiO(2), UV-TiO(2)) were prepared by mixing varying concentrations of H(2)O(2 )and/or TiO(2 )photocatalyst with MB solution. For H(2)O(2)-containing solutions (VL-TiO(2)+H(2)O(2), UV-TiO(2)+H(2)O(2), and H(2)O(2)), the concentration of H(2)O(2) was adjusted to 3.5%. For the four different light sources, low- and high-intensity halogen lamps and blue LED LCUs were used. All the experimental solutions were irradiated by each of the light sources for 7 minutes, and the absorbance at 660 nm was measured every 30 seconds to determine the concentration of MB as an indicator of the bleaching effect. On the interaction between the effects of light source and bleaching treatment, the high-intensity halogen with VL-TiO(2)+H(2)O(2) caused the most significant reduction in MB concentration. On the effect of light sources, the halogen lamps resulted in a greater bleaching effect than the blue LED LCUs.

  4. Device characterization of the VCSEL-on-silicon as an on chip light source

    NASA Astrophysics Data System (ADS)

    Kwack, Myung-Joon; Jang, Ki-Seok; Joo, Jiho; Park, Hyundai; Oh, Jin Hyuk; Park, Jaegyu; Kim, Sanggi; Kim, Gyungock

    2016-03-01

    Advancement of silicon photonics technology can offer a new dimension in data communications with un-precedent bandwidth. Increasing the integration level in the silicon photonics is required to develop compact high-performance chip-level optical interconnects for future systems. Especially, monolithic integration of light source on a silicon wafer is important for future silicon photonic integrated circuits, since realizing a compact on-chip light source on a silicon wafer is a serious issue which impedes practical implementation of the silicon photonic interconnects. At present, due to the lack of a practical light source based on Group IV elements, flip chip-bonded or packaged lasers based on III-V semiconductor are usually being used as external light sources, to feed silicon modulators on SOI wafers to complete a photonic transmitter, except the reported silicon hybrid lasers monolithic-integrated on SOI wafers. To overcome above problem, we have proposed a compact on-chip light source, the directly monolithic-integrated VCSEL on a bulk silicon wafer (VCSEL-on-Si), based on the transplanted epitaxial film by substrate lift-off process and following device-fabrication on the bulk Si wafer. This can offer practical low-power-consumption light sources integrated on a silicon wafer, which can provide a complete chip-level I/O set when combined with monolithic-integrated vertical-illumination Ge-on-Si photodetectors on the same silicon wafer. In this work, we report the characterization of direct-modulation VCSELs-on-Si for λ ~850 nm with CW optical output power > ~2 mW and the threshold current < ~3 mA, over 10 Gb/s operations. We also discuss about the thermal characteristics of the VCSELs-on-Si.

  5. The Development of the Undulator Controls Module at the Linac Coherent Light Source

    SciTech Connect

    Alarcon, A.D.; /SLAC

    2009-12-11

    The Linac Coherent Light Source, LCLS, at the SLAC National Accelerator Laboratory, SNAL, is the first hard x-ray Free Electron Laser. The Undulator Controls Module, UCM, controls five cams and two translation stages that regulate the position of each of the 33 permanent undulator magnet segments within 10 microns. The UCM package, hardware and software, was designed and built by the Advanced Photon Source at Argonne. Important lessons were learned throughout the collaborative design, installation, testing, and commissioning periods that could be invaluable to future similar controls projects.

  6. Developing electron beam bunching technology for improving light sources

    SciTech Connect

    Carlsten, B.E.; Chan, K.C.D.; Feldman, D.W.

    1997-08-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of this project was to develop a new electron bunch compression technology, experimentally demonstrate subpicosecond compression of bunches with charges on the order of 1 nC, and to theoretically investigate fundamental limitations to electron bunch compression. All of these goals were achieved, and in addition, the compression system built for this project was used to generate 22 nm light in a plasma-radiator light source.

  7. Method and apparatus for acquisition and tracking of light sources in a transient event rich environment

    NASA Technical Reports Server (NTRS)

    Kissh, Frank (Inventor); Flynn, David (Inventor); Fowski, Walter (Inventor); Abreu, Rene (Inventor); Miklus, Kenneth (Inventor); Bolin, Kenneth (Inventor)

    1993-01-01

    A method and apparatus for tracking a light source in a transient event rich environment locks on to a light source incident on a field-of-view 1 of a charge-coupled-device (CCD) array 6, validates the permanence of said light source and transmits data relating to the brilliance and location of said light source if said light source is determined to be permanent.

  8. Local transverse coupling impedance measurements in a synchrotron light source from turn-by-turn acquisitions

    NASA Astrophysics Data System (ADS)

    Carlà, Michele; Benedetti, Gabriele; Günzel, Thomas; Iriso, Ubaldo; Martí, Zeus

    2016-12-01

    Transverse beam coupling impedance is a source of beam instabilities that limits the machine performance in circular accelerators. Several beam based techniques have been used to measure the transverse impedance of an accelerator, usually based on the optics distortion produced by the impedance source itself. Beam position monitor turn-by-turn analysis for impedance characterization has been usually employed in large circumference machines, while synchrotron light sources have mainly used slow orbit based techniques. Instead, the work presented in this paper uses for the first time turn-by-turn data at ALBA to advance the measurement technique into the range of the typically small impedance values of modern light sources. We have measured local impedance contributions through the observation of phase advance versus bunch charge using the betatron oscillations excited with a fast dipole kicker. The ALBA beam position monitor system and the precision of the turn-by-turn analysis allowed to characterize the main sources of transverse impedance, in good agreement with the model values, including the impedance of an in-vacuum undulator.

  9. Applications of advanced aerodynamic technology to light aircraft.

    NASA Technical Reports Server (NTRS)

    Crane, H. L.; Mcghee, R. J.; Kohlman, D. L.

    1973-01-01

    This paper discusses a project for adapting advanced technology, much of it borrowed from the jet transport, to general aviation design practice. The NASA funded portion of the work began in 1969 at the University of Kansas and resulted in a smaller, experimental wing with spoilers and powerful flap systems for a Cessna Cardinal airplane. Some flight data and research pilot comments are presented. The project was expanded in 1972 to include a light twin-engine airplane. For the twin there was the added incentive of a potential increase in single-engine climb performance. The use of a new high-lift Whitcomb airfoil is planned for both the wing and the propellers. Preliminary data on the characteristics of the new airfoil are discussed. The configuration of an experimental wing for a Piper Seneca PA-34 and estimated airplane performance with this wing are discussed.

  10. Simulating Dicke-like superradiance with classical light sources

    NASA Astrophysics Data System (ADS)

    Bhatti, D.; Oppel, S.; Wiegner, R.; Agarwal, G. S.; von Zanthier, J.

    2016-07-01

    In this paper we investigate the close relationship between Dicke superradiance, originally predicted for an ensemble of two-level atoms in entangled states, and the Hanbury Brown and Twiss effect, initially established in astronomy to determine the dimensions of classical light sources such as stars. By studying the state evolution of the fields produced by classical sources—defined by a positive Glauber-Sudarshan P function—when recording intensity correlations of higher order in a generalized Hanbury Brown and Twiss setup we find that the angular distribution of the last detected photon, apart from an offset, is identical to the superradiant emission pattern generated by an ensemble of two-level atoms in entangled symmetric Dicke states. We show that the phenomenon derives from projective measurements induced by the measurement of photons in the far field of the sources and the permutative superposition of quantum paths identical to those leading to superradiance in the case of single photon emitters. We thus point out an important similarity between classical sources and quantum emitters upon detection of photons if the particular photon source remains unknown. We finally present a compact result for the characteristic functional which generates intensity correlations of arbitrary order for any kind of light source.

  11. New markets and new light-sources for projection

    NASA Astrophysics Data System (ADS)

    Moench, Holger

    2008-02-01

    Projection systems have the unique advantage that they can produce large images from compact devices. The specialized UHP and Ujoy lamps enabled a tremendous progress towards compact and highly efficient systems. Beyond the existing markets of rear and professional front projection new applications are possible addressing personal projection and micro-projection. These new applications can profit from laser light sources. Today laser technology is still costly and complicated especially for green wavelengths. Several competing approaches for a green laser are reviewed and the basic requirements of a laser source for projection are described.

  12. Ultraminiature broadband light source with spiral shaped filament

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret L. (Inventor); Collura, Joseph S. (Inventor); Helvajian, Henry (Inventor); Pocha, Michael D. (Inventor); Meyer, Glenn A. (Inventor); McConaghy, Charles F. (Inventor); Olsen, Barry L. (Inventor); Hansen, William W (Inventor)

    2012-01-01

    An ultraminiature light source using a double-spiral shaped tungsten filament includes end contact portions which are separated to allow for radial and length-wise unwinding of the spiral. The double-spiral filament is spaced relatively far apart at the end portions thereof so that contact between portions of the filament upon expansion is avoided. The light source is made by fabricating a double-spiral ultraminiature tungsten filament from tungsten foil and housing the filament in a ceramic package having a reflective bottom and a well wherein the filament is suspended. A vacuum furnace brazing process attaches the filament to contacts of the ceramic package. Finally, a cover with a transparent window is attached onto the top of the ceramic package by solder reflow in a second vacuum furnace process to form a complete hermetically sealed package.

  13. New robust and highly customizable light source management system

    NASA Astrophysics Data System (ADS)

    Minegishi, Yuji; Takahisa, Kenji; Ochiai, Hideyuki; Ohta, Takeshi; Enami, Tatsuo

    2015-03-01

    In semiconductor lithography, light sources play a significant role in the wafer production process as well as impacting the manufacturing cost per wafer. Chip manufacturers going forward will be challenged to develop new ways to become more cost effective than their competitors, and the software tools necessary to compete in this environment must be capable of effectively adapting to the unique needs of each manufacturer. Gigaphoton has developed a new highly customizable software system for managing light sources. It not only offers a simple and intuitive user interface that can be operated using a standard web browser on PCs, tablets, and smartphones, but also a platform for users and third parties to develop unique extensions and optimizations.

  14. X-ray detectors at the Linac Coherent Light Source

    DOE PAGES

    Blaj, Gabriel; Caragiulo, Pietro; Carini, Gabriella; ...

    2015-04-21

    Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a newmore » generation of cameras under development at SLAC, is introduced.« less

  15. Hyperspectral retinal imaging with a spectrally tunable light source

    NASA Astrophysics Data System (ADS)

    Francis, Robert P.; Zuzak, Karel J.; Ufret-Vincenty, Rafael

    2011-03-01

    Hyperspectral retinal imaging can measure oxygenation and identify areas of ischemia in human patients, but the devices used by current researchers are inflexible in spatial and spectral resolution. We have developed a flexible research prototype consisting of a DLP®-based spectrally tunable light source coupled to a fundus camera to quickly explore the effects of spatial resolution, spectral resolution, and spectral range on hyperspectral imaging of the retina. The goal of this prototype is to (1) identify spectral and spatial regions of interest for early diagnosis of diseases such as glaucoma, age-related macular degeneration (AMD), and diabetic retinopathy (DR); and (2) define required specifications for commercial products. In this paper, we describe the challenges and advantages of using a spectrally tunable light source for hyperspectral retinal imaging, present clinical results of initial imaging sessions, and describe how this research can be leveraged into specifying a commercial product.

  16. X-ray detectors at the Linac Coherent Light Source

    PubMed Central

    Blaj, Gabriel; Caragiulo, Pietro; Carini, Gabriella; Carron, Sebastian; Dragone, Angelo; Freytag, Dietrich; Haller, Gunther; Hart, Philip; Hasi, Jasmine; Herbst, Ryan; Herrmann, Sven; Kenney, Chris; Markovic, Bojan; Nishimura, Kurtis; Osier, Shawn; Pines, Jack; Reese, Benjamin; Segal, Julie; Tomada, Astrid; Weaver, Matt

    2015-01-01

    Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a new generation of cameras under development at SLAC, is introduced. PMID:25931071

  17. X-ray detectors at the Linac Coherent Light Source

    SciTech Connect

    Blaj, Gabriel; Caragiulo, Pietro; Carini, Gabriella; Carron, Sebastian; Dragone, Angelo; Freytag, Dietrich; Haller, Gunther; Hart, Philip; Hasi, Jasmine; Herbst, Ryan; Herrmann, Sven; Kenney, Chris; Markovic, Bojan; Nishimura, Kurtis; Osier, Shawn; Pines, Jack; Reese, Benjamin; Segal, Julie; Tomada, Astrid; Weaver, Matt

    2015-04-21

    Free-electron lasers (FELs) present new challenges for camera development compared with conventional light sources. At SLAC a variety of technologies are being used to match the demands of the Linac Coherent Light Source (LCLS) and to support a wide range of scientific applications. In this paper an overview of X-ray detector design requirements at FELs is presented and the various cameras in use at SLAC are described for the benefit of users planning experiments or analysts looking at data. Features and operation of the CSPAD camera, which is currently deployed at LCLS, are discussed, and the ePix family, a new generation of cameras under development at SLAC, is introduced.

  18. Invited Review Article: Advanced light microscopy for biological space research

    NASA Astrophysics Data System (ADS)

    De Vos, Winnok H.; Beghuin, Didier; Schwarz, Christian J.; Jones, David B.; van Loon, Jack J. W. A.; Bereiter-Hahn, Juergen; Stelzer, Ernst H. K.

    2014-10-01

    As commercial space flights have become feasible and long-term extraterrestrial missions are planned, it is imperative that the impact of space travel and the space environment on human physiology be thoroughly characterized. Scrutinizing the effects of potentially detrimental factors such as ionizing radiation and microgravity at the cellular and tissue level demands adequate visualization technology. Advanced light microscopy (ALM) is the leading tool for non-destructive structural and functional investigation of static as well as dynamic biological systems. In recent years, technological developments and advances in photochemistry and genetic engineering have boosted all aspects of resolution, readout and throughput, rendering ALM ideally suited for biological space research. While various microscopy-based studies have addressed cellular response to space-related environmental stressors, biological endpoints have typically been determined only after the mission, leaving an experimental gap that is prone to bias results. An on-board, real-time microscopical monitoring device can bridge this gap. Breadboards and even fully operational microscope setups have been conceived, but they need to be rendered more compact and versatile. Most importantly, they must allow addressing the impact of gravity, or the lack thereof, on physiologically relevant biological systems in space and in ground-based simulations. In order to delineate the essential functionalities for such a system, we have reviewed the pending questions in space science, the relevant biological model systems, and the state-of-the art in ALM. Based on a rigorous trade-off, in which we recognize the relevance of multi-cellular systems and the cellular microenvironment, we propose a compact, but flexible concept for space-related cell biological research that is based on light sheet microscopy.

  19. Invited Review Article: Advanced light microscopy for biological space research

    SciTech Connect

    De Vos, Winnok H.; Beghuin, Didier; Schwarz, Christian J.; Jones, David B.; Loon, Jack J. W. A. van

    2014-10-15

    As commercial space flights have become feasible and long-term extraterrestrial missions are planned, it is imperative that the impact of space travel and the space environment on human physiology be thoroughly characterized. Scrutinizing the effects of potentially detrimental factors such as ionizing radiation and microgravity at the cellular and tissue level demands adequate visualization technology. Advanced light microscopy (ALM) is the leading tool for non-destructive structural and functional investigation of static as well as dynamic biological systems. In recent years, technological developments and advances in photochemistry and genetic engineering have boosted all aspects of resolution, readout and throughput, rendering ALM ideally suited for biological space research. While various microscopy-based studies have addressed cellular response to space-related environmental stressors, biological endpoints have typically been determined only after the mission, leaving an experimental gap that is prone to bias results. An on-board, real-time microscopical monitoring device can bridge this gap. Breadboards and even fully operational microscope setups have been conceived, but they need to be rendered more compact and versatile. Most importantly, they must allow addressing the impact of gravity, or the lack thereof, on physiologically relevant biological systems in space and in ground-based simulations. In order to delineate the essential functionalities for such a system, we have reviewed the pending questions in space science, the relevant biological model systems, and the state-of-the art in ALM. Based on a rigorous trade-off, in which we recognize the relevance of multi-cellular systems and the cellular microenvironment, we propose a compact, but flexible concept for space-related cell biological research that is based on light sheet microscopy.

  20. Invited review article: Advanced light microscopy for biological space research.

    PubMed

    De Vos, Winnok H; Beghuin, Didier; Schwarz, Christian J; Jones, David B; van Loon, Jack J W A; Bereiter-Hahn, Juergen; Stelzer, Ernst H K

    2014-10-01

    As commercial space flights have become feasible and long-term extraterrestrial missions are planned, it is imperative that the impact of space travel and the space environment on human physiology be thoroughly characterized. Scrutinizing the effects of potentially detrimental factors such as ionizing radiation and microgravity at the cellular and tissue level demands adequate visualization technology. Advanced light microscopy (ALM) is the leading tool for non-destructive structural and functional investigation of static as well as dynamic biological systems. In recent years, technological developments and advances in photochemistry and genetic engineering have boosted all aspects of resolution, readout and throughput, rendering ALM ideally suited for biological space research. While various microscopy-based studies have addressed cellular response to space-related environmental stressors, biological endpoints have typically been determined only after the mission, leaving an experimental gap that is prone to bias results. An on-board, real-time microscopical monitoring device can bridge this gap. Breadboards and even fully operational microscope setups have been conceived, but they need to be rendered more compact and versatile. Most importantly, they must allow addressing the impact of gravity, or the lack thereof, on physiologically relevant biological systems in space and in ground-based simulations. In order to delineate the essential functionalities for such a system, we have reviewed the pending questions in space science, the relevant biological model systems, and the state-of-the art in ALM. Based on a rigorous trade-off, in which we recognize the relevance of multi-cellular systems and the cellular microenvironment, we propose a compact, but flexible concept for space-related cell biological research that is based on light sheet microscopy.

  1. Ground motion measurements at the LBL Light Source site, the Bevatron and at SLAC

    SciTech Connect

    Green, M.A.; Majer, E.I.; More, V.D.; O'Connell, D.R.; Shilling, R.C.

    1986-12-01

    This report describes the technique for measuring ground motion at the site of the 1.0 to 2.0 GeV Synchrotron Radiation Facility which was known as the Advanced Light Source (in 1983 when the measurements were taken). The results of ground motion measurements at the Light Source site at Building 6 at LBL are presented. As comparison, ground motion measurements were made at the Byerly Tunnel, the Bevatron, Blackberry Canyon, and SLAC at the Spear Ring. Ground Motion at the Light Source site was measured in a band from 4 to 100 Hz. The measured noise is primarily local in origin and is not easily transported through LBL soils. The background ground motion is for the most part less than 0.1 microns. Localized truck traffic near Building 6 and the operation of the cranes in the building can result in local ground motions of a micron or more for short periods of time. The background motion at Building 6 is between 1 and 2 orders of magnitude higher than ground motion in a quiet seismic tunnel, which is representative of quiet sites worldwide. The magnitude of the ground motions at SLAC and the Bevatron are comparable to ground motions measured at the Building 6 Light Source site. However, the frequency signature of each site is very different.

  2. Electron Beam Collimation for the Next Generation Light Source

    SciTech Connect

    Steier, C.; Emma, P.; Nishimura, H.; Papadopoulos, C.; Sannibale, F.

    2013-05-20

    The Next Generation Light Source will deliver high (MHz) repetition rate electron beams to an array of free electron lasers. Because of the significant average current in such a facility, effective beam collimation is extremely important to minimize radiation damage to undulators, prevent quenches of superconducting cavities, limit dose rates outside of the accelerator tunnel and prevent equipment damage. This paper describes the early conceptual design of a collimation system, as well as initial results of simulations to test its effectiveness.

  3. Experimental stations at I13 beamline at Diamond Light Source

    NASA Astrophysics Data System (ADS)

    Pešić, Z. D.; De Fanis, A.; Wagner, U.; Rau, C.

    2013-03-01

    The I13 beamline of Diamond Light Source has been operational since December 2011. The beamline encompass two fully independent branches devoted to coherent imaging experiments (coherent x-ray diffraction, coherent diffraction imaging and ptychography) and x-ray imaging (in-line phase contrast imaging, tomography and full-field microscopy). This paper gives an overview of the current status of experimental stations on both branches and outlines planned developments.

  4. National Synchrotron Light Source safety-analysis report

    SciTech Connect

    Batchelor, K.

    1982-07-01

    This document covers all of the safety issues relating to the design and operation of the storage rings and injection system of the National Synchrotron Light Source. The building systems for fire protection, access and egress are described together with air and other gaseous control or venting systems. Details of shielding against prompt bremstrahlung radiation and synchrotron radiation are described and the administrative requirements to be satisfied for operation of a beam line at the facility are given.

  5. An overview of the planned advanced neutron source facility

    SciTech Connect

    West, C.D.

    1990-01-01

    The Advanced Neutron Source (ANS), now in the conceptual design stage, will be a new user facility for neutron research, including neutron beam experiments, materials irradiation testing and materials analysis capabilities, and production facilities for transuranic and lighter isotopes. The neutron source is to be the world's highest flux beam reactor and is based on existing reactor technology to minimize safety issues. The preferred fuel, U{sub 3}Si{sub 2}, has been tested in operating reactors in the United States, Japan, and Europe. The core is cooled, moderated, and reflected by heavy water, common practice for research reactors. 3 refs., 9 figs., 3 tabs.

  6. Science and Technology of Future Light Sources: A White Paper

    SciTech Connect

    Bergmann, Uwe; Corlett, John; Dierker, Steve; Falcone, Roger; Galayda, John; Gibson, Murray; Hastings, Jerry; Hettel, Bob; Hill, John; Hussain, Zahid; Kao, Chi-Chang; Kirz, a= Janos; Long, Gabrielle; McCurdy, Bill; Raubenheimer, Tor; Sannibale, Fernando; Seeman, John; Shen, Z.-X.; Shenoy, Gopal; Schoenlein, Bob; Shen, Qun; /Argonne /Brookhaven /LBL, Berkeley /SLAC, SSRL

    2009-02-03

    Many of the important challenges facing humanity, including developing alternative sources of energy and improving health, are being addressed by advances that demand the improved understanding and control of matter. While the visualization, exploration, and manipulation of macroscopic matter have long been technological goals, scientific developments in the twentieth century have focused attention on understanding matter on the atomic scale through the underlying framework of quantum mechanics. Of special interest is matter that consists of natural or artificial nanoscale building blocks defined either by atomic structural arrangements or by electron or spin formations created by collective correlation effects (Figure 1.1). The essence of the challenge to the scientific community has been expressed in five grand challenges for directing matter and energy recently formulated by the Basic Energy Sciences Advisory Committee [1]. These challenges focus on increasing our understanding of, and ultimately control of, matter at the level of atoms, electrons. and spins, as illustrated in Figure 1.1, and serve the entire range of science from advanced materials to life sciences. Meeting these challenges will require new tools that extend our reach into regions of higher spatial, temporal, and energy resolution. X-rays with energies above 10 keV offer capabilities extending beyond the nanoworld shown in Figure 1.1 due to their ability to penetrate into optically opaque or thick objects. This opens the door to combining atomic level information from scattering studies with 3D information on longer length scales from real space imaging with a resolution approaching 1 nm. The investigation of multiple length scales is important in hierarchical structures, providing knowledge about function of living organisms, the atomistic origin of materials failure, the optimization of industrial synthesis, or the working of devices. Since the fundamental interaction that holds matter

  7. Access control and interlock system at the Advanced Photon Source

    SciTech Connect

    Forrestal, J.; Hogrefe, R.; Knott, M.; McDowell, W.; Reigle, D.; Solita, L.; Koldenhoven, R.; Haid, D.

    1997-08-01

    The Advanced Photon Source (APS) consists of a linac, position accumulator ring (PAR), booster synchrotron, storage ring, and up to 70 experimental beamlines. The Access Control and Interlock System (ACIS) utilizes redundant programmable logic controllers (PLCs) and a third hard-wired chain to protect personnel from prompt radiation generated by the linac, PAR, synchrotron, and storage ring. This paper describes the ACIS`s design philosophy, configuration, hardware, functionality, validation requirements, and operational experience.

  8. Ultraviolet light output of compact fluorescent lamps: comparison to conventional incandescent and halogen residential lighting sources.

    PubMed

    Nuzum-Keim, A D; Sontheimer, R D

    2009-05-01

    Patients with photosensitive dermatologic and systemic diseases often question the ultraviolet light (UVL) output of household lighting sources. Such individuals have increasing concern about potential UVL exposure from energy-efficient compact fluorescent lamps (CFL), as little data have been presented concerning their UVL output. The objective was to compare, via pilot study, the levels of ultraviolet A (UVA) and ultraviolet B (UVB) leak between residential lighting sources. Equivalent wattage CFL, incandescent and halogen bulbs were purchased from local retailers in Oklahoma City, Oklahoma, USA. The UVA and UVB outputs of these sources were measured under controlled conditions at 10, 25, 50, 100 and 150 cm away from the light source using an IL-1700 research radiometer equipped with UVA and UVB detectors. Negligible UVB and UVA was detected at 100 and 150 cm. Therefore, data were analysed from measurements at 10, 25 and 50 cm only. The results demonstrated UVA leak highest from incandescent and halogen bulbs, and UVB leak highest from CFL. The overall UVA/UVB leak was lowest from CFL shielded during the manufacturing process. In conclusion, patients with photosensitivity have choices depending on their relative risk from different UVL wavelength spectra. UVB exposure risk may be reduced the greatest by utilising CFL with manufacturer-provided shields.

  9. Stray light in cone beam optical computed tomography: II. Reduction using a convergent light source

    NASA Astrophysics Data System (ADS)

    Dekker, Kurtis H.; Battista, Jerry J.; Jordan, Kevin J.

    2016-04-01

    Optical cone beam computed tomography (CBCT) using a broad beam and CCD camera is a fast method for densitometry of 3D optical gel dosimeters. However, diffuse light sources introduce considerable stray light into the imaging system, leading to underestimation of attenuation coefficients and non-uniformities in CT images unless corrections are applied to each projection image. In this study, the light source of a commercial optical CT scanner is replaced with a convergent cone beam source consisting of almost exclusively image forming primary rays. The convergent source is achieved using a small isotropic source and a Fresnel lens. To characterize stray light effects, full-field cone beam CT imaging is compared to fan beam CT (FBCT) using a 1 cm high fan beam aperture centered on the optic axis of the system. Attenuating liquids are scanned within a large 96 mm diameter uniform phantom and in a small 13.5 mm diameter finger phantom. For the uniform phantom, cone and fan beam CT attenuation coefficients agree within a maximum deviation of (1  ±  2)% between mean values over a wide range from 0.036 to 0.43 cm-1. For the finger phantom, agreement is found with a maximum deviation of (4  ±  2)% between mean values over a range of 0.1-0.47 cm-1. With the convergent source, artifacts associated with refractive index mismatch and vessel optical features are more pronounced. Further optimization of the source size to achieve a balance between quantitative accuracy and artifact reduction should enable practical, accurate 3D dosimetry, avoiding time consuming 3D scatter measurements.

  10. Stray light in cone beam optical computed tomography: II. Reduction using a convergent light source.

    PubMed

    Dekker, Kurtis H; Battista, Jerry J; Jordan, Kevin J

    2016-04-07

    Optical cone beam computed tomography (CBCT) using a broad beam and CCD camera is a fast method for densitometry of 3D optical gel dosimeters. However, diffuse light sources introduce considerable stray light into the imaging system, leading to underestimation of attenuation coefficients and non-uniformities in CT images unless corrections are applied to each projection image. In this study, the light source of a commercial optical CT scanner is replaced with a convergent cone beam source consisting of almost exclusively image forming primary rays. The convergent source is achieved using a small isotropic source and a Fresnel lens. To characterize stray light effects, full-field cone beam CT imaging is compared to fan beam CT (FBCT) using a 1 cm high fan beam aperture centered on the optic axis of the system. Attenuating liquids are scanned within a large 96 mm diameter uniform phantom and in a small 13.5 mm diameter finger phantom. For the uniform phantom, cone and fan beam CT attenuation coefficients agree within a maximum deviation of (1  ±  2)% between mean values over a wide range from 0.036 to 0.43 cm(-1). For the finger phantom, agreement is found with a maximum deviation of (4  ±  2)% between mean values over a range of 0.1-0.47 cm(-1). With the convergent source, artifacts associated with refractive index mismatch and vessel optical features are more pronounced. Further optimization of the source size to achieve a balance between quantitative accuracy and artifact reduction should enable practical, accurate 3D dosimetry, avoiding time consuming 3D scatter measurements.

  11. Sole-Source Lighting for Controlled-Environment Agriculture

    NASA Technical Reports Server (NTRS)

    Mitchell.Cary; Stutte, Gary W.

    2015-01-01

    Since plants on Earth evolved under broad-spectrum solar radiation, anytime they are grown exclusively under electric lighting that does not contain all wavelengths in similar proportion to those in sunlight, plant appearance and size could be uniquely different. Nevertheless, plants have been grown for decades under fluorescent (FL) (1) + incandescent (IN) (2) lamps as a sole source of lighting (SSL), and researchers have become comfortable that, in certain proportions of FL + IN for a given species, plants can appear "normal" relative to their growth outdoors. The problem with using such traditional SSLs for commercial production typically is short lamp lifespans and not obtaining enough photosynthetically active radiation (PAR, 400-700 nm) when desired. These limitations led to supplementation of FL + IN lamp outputs with longer-lived, high-intensity discharge (HID) lamps in growth chambers (3). As researchers became comfortable that mixes of orange-biased high-pressure sodium (HPS) and blue-biased metal halide (MH) HIDs together also could give normal plant growth at higher intensities, growth chambers and phytotrons subsequently were equipped mainly with HID lamps, with their intense thermal output filtered out by ventilated light caps or thermal-controlled water barriers. For the most part, IN and HID lamps have found a home in commercial protected horticulture, usually for night-break photoperiod lighting (IN) or for seasonal supplemental lighting (mostly HPS) in greenhouses. However, lack of economically viable options for SSL have held back aspects of year-round indoor agriculture from taking off commercially.

  12. Inhomogeneous Magnetic Field Geometry Light Ion Helicon Plasma Source

    NASA Astrophysics Data System (ADS)

    Mori, Yoshitaka; Nakashima, Hideki; Goulding, R. H.; Carter Baity, M. D., Jr.; Sparks, D. O.; Barber, G. C.; White, K. F.; Jaeger, E. F.; Chang-Díaz, F. R.; Squire, J. P.

    2002-11-01

    Helicon plasma source is a well-known high-density plasma source for many applications including plasma processing and fusion. However, most helicon research has been focused on a uniform static magnetic field and relatively heavy ions. Light ion helicon operation is more sensitive to magnetic field strength and geometry than heavy ions. The axially inhomogeneous Mini-Radio Frequency Test Facility (Mini-RFTF) has a capability for controlling static magnetic fields then is applicative for light ion source plasma operation. Inhomogeneous static magnetic field geometry also can procedure a high velocity to plasma exhaust when combined with ICRF heating enabling the possibility of use in plasma propulsion. In this poster, we will show how the source has been optimized for a hydrogen operation and a specific plasma propulsion concept: The Variable Specific Impulse Magnetoplasma Rocket (VASIMR). Measurements of the rf magnetic fields and profile of plasma parameters for several magnetic field strengths and geometries will be discussed. Comparisons with a RF modeling code EMIR3 also will be reported here.

  13. Environmental Remediation Science at Beamline X26A at the National Synchrotron Light Source- Final Report

    SciTech Connect

    Bertsch, Paul

    2013-11-07

    The goal of this project was to provide support for an advanced X-ray microspectroscopy facility at the National Synchrotron Light Source, Brookhaven National Laboratory. This facility is operated by the University of Chicago and the University of Kentucky. The facility is available to researchers at both institutions as well as researchers around the globe through the general user program. This facility was successfully supported during the project period. It provided access to advanced X-ray microanalysis techniques which lead to fundamental advances in understanding the behavior of contaminants and geochemistry that is applicable to environmental remediation of DOE legacy sites as well as contaminated sites around the United States and beyond.

  14. Ideas for a Future PEP-X Light Source

    SciTech Connect

    Hettel, R.O.; Bane, K.L.F.; Bentson, L.D.; Bertsche, Kirk J.; Brennan, S.M.; Cai, Y.; Chao, A.; DeBarger, S.; Dolgashev, V.A.; Huang, X.; Huang, Z.; Kharakh, D.; Nosochkov, Y.; Rabedeau, T.; Safranek, J.A.; Seeman, J.; Stohr, J.; Stupakov, G.V.; Tantawi, S.G.; Wang, L.; Wang, M.H.; /SLAC /Stanford U., Phys. Dept. /UCLA

    2011-11-02

    SLAC is developing a long-range plan to transfer the evolving scientific programs at SSRL from the SPEAR3 light source to a much higher performing synchrotron source -- PEP-X -- a new storage ring that would occupy the existing PEP-II tunnel and support two experimental halls, each containing 16 x-ray beam lines. Operating at 4.5 GeV and 1.5 A with a horizontal emittance of 0.14 nm-rad, reached using 90 m of damping wigglers, PEP-X would have an order of magnitude higher average brightness and flux in the 1-{angstrom} x-ray range than any existing or planned future storage ring sources. Higher brightness in the soft x-ray regime might be reached with partial lasing in long undulators, and high peak brightness could be reached with seeded FEL emission. The status of preliminary studies of PEP-X is presented.

  15. Multifrequency light curves of low-frequency variable radio sources

    NASA Technical Reports Server (NTRS)

    Altschuler, D. R.; Broderick, J. J.; Dennison, B.; Mitchell, K. J.; Odell, S. L.; Condon, J. J.; Payne, H. E.

    1984-01-01

    Light curves for the low-frequency variable sources AO 0235 + 16, NRAO 140, PKS 1117 + 14, DA 406, CTA 102, and 3C 454.3, obtained in monthly observations at 318, 430, and 606 MHz using the 305-m telescope at Arecibo and in bimonthly observations at 880 MHz and 1.4 GHz using the 91-m Green Bank transit telescope during 1980-1983, are presented and analyzed. AO 0235 + 16 is found to have basically canonical variability which is attributed to relativistically moving evolving synchrotron components; but in the other sources, strong simultaneous variations at 318, 430, and 606 MHz are observed to be greatly diminished in amplitude at 880 MHz and 1.4 GHz, confirming the existence of the intermediate-frequency gap at about 1 GHz proposed by Spangler and Cotton (1981). The possibility that a second variability mechanism is active in these sources is explored.

  16. The linac coherent light source single particle imaging road map

    PubMed Central

    Aquila, A.; Barty, A.; Bostedt, C.; Boutet, S.; Carini, G.; dePonte, D.; Drell, P.; Doniach, S.; Downing, K. H.; Earnest, T.; Elmlund, H.; Elser, V.; Gühr, M.; Hajdu, J.; Hastings, J.; Hau-Riege, S. P.; Huang, Z.; Lattman, E. E.; Maia, F. R. N. C.; Marchesini, S.; Ourmazd, A.; Pellegrini, C.; Santra, R.; Schlichting, I.; Schroer, C.; Spence, J. C. H.; Vartanyants, I. A.; Wakatsuki, S.; Weis, W. I.; Williams, G. J.

    2015-01-01

    Intense femtosecond x-ray pulses from free-electron laser sources allow the imaging of individual particles in a single shot. Early experiments at the Linac Coherent Light Source (LCLS) have led to rapid progress in the field and, so far, coherent diffractive images have been recorded from biological specimens, aerosols, and quantum systems with a few-tens-of-nanometers resolution. In March 2014, LCLS held a workshop to discuss the scientific and technical challenges for reaching the ultimate goal of atomic resolution with single-shot coherent diffractive imaging. This paper summarizes the workshop findings and presents the roadmap toward reaching atomic resolution, 3D imaging at free-electron laser sources. PMID:26798801

  17. Multifrequency light curves of low-frequency variable radio sources

    NASA Astrophysics Data System (ADS)

    Altschuler, D. R.; Broderick, J. J.; Dennison, B.; Mitchell, K. J.; Odell, S. L.; Condon, J. J.; Payne, H. E.

    1984-12-01

    Light curves for the low-frequency variable sources AO 0235 + 16, NRAO 140, PKS 1117 + 14, DA 406, CTA 102, and 3C 454.3, obtained in monthly observations at 318, 430, and 606 MHz using the 305-m telescope at Arecibo and in bimonthly observations at 880 MHz and 1.4 GHz using the 91-m Green Bank transit telescope during 1980-1983, are presented and analyzed. AO 0235 + 16 is found to have basically canonical variability which is attributed to relativistically moving evolving synchrotron components; but in the other sources, strong simultaneous variations at 318, 430, and 606 MHz are observed to be greatly diminished in amplitude at 880 MHz and 1.4 GHz, confirming the existence of the intermediate-frequency gap at about 1 GHz proposed by Spangler and Cotton (1981). The possibility that a second variability mechanism is active in these sources is explored.

  18. The linac coherent light source single particle imaging road map

    DOE PAGES

    Aquila, A.; Barty, A.; Bostedt, C.; ...

    2015-07-01

    Intense femtosecond x-ray pulses from free-electron laser sources allow the imaging of individual particles in a single shot. Early experiments at the Linac Coherent Light Source (LCLS) have led to rapid progress in the field and, so far, coherent diffractive images have been recorded from biological specimens, aerosols, and quantum systems with a few-tens-of-nanometers resolution. In March 2014, LCLS held a workshop to discuss the scientific and technical challenges for reaching the ultimate goal of atomic resolution with single-shot coherent diffractive imaging. This paper summarizes the workshop findings and presents the roadmap toward reaching atomic resolution, 3D imaging at free-electronmore » laser sources.« less

  19. The linac coherent light source single particle imaging road map

    SciTech Connect

    Aquila, A.; Barty, A.; Bostedt, C.; Boutet, S.; Carini, G.; dePonte, D.; Drell, P.; Doniach, S.; Downing, K. H.; Earnest, T.; Elmlund, H.; Elser, V.; Gühr, M.; Hajdu, J.; Hastings, J.; Hau-Riege, S. P.; Huang, Z.; Lattman, E. E.; Maia, F. R.N.C.; Marchesini, S.; Ourmazd, A.; Pellegrini, C.; Schlichting, I.; Schroer, C.; Spence, J. C. H.; Vartanyants, I. A.; Wakatsuki, S.; Weis, W. I.; Williams, G. J.

    2015-07-01

    Intense femtosecond x-ray pulses from free-electron laser sources allow the imaging of individual particles in a single shot. Early experiments at the Linac Coherent Light Source (LCLS) have led to rapid progress in the field and, so far, coherent diffractive images have been recorded from biological specimens, aerosols, and quantum systems with a few-tens-of-nanometers resolution. In March 2014, LCLS held a workshop to discuss the scientific and technical challenges for reaching the ultimate goal of atomic resolution with single-shot coherent diffractive imaging. This paper summarizes the workshop findings and presents the roadmap toward reaching atomic resolution, 3D imaging at free-electron laser sources.

  20. Linac Coherent Light Source: The first five years

    NASA Astrophysics Data System (ADS)

    Bostedt, Christoph; Boutet, Sébastien; Fritz, David M.; Huang, Zhirong; Lee, Hae Ja; Lemke, Henrik T.; Robert, Aymeric; Schlotter, William F.; Turner, Joshua J.; Williams, Garth J.

    2016-01-01

    A new scientific frontier opened in 2009 with the start of operations of the world's first x-ray free-electron laser (FEL), the Linac Coherent Light Source (LCLS), at SLAC National Accelerator Laboratory. LCLS provides femtosecond pulses of x rays (270 eV to 11.2 keV) with very high peak brightness to access new domains of ultrafast x-ray science. This article presents the fundamental FEL physics and outlines the LCLS source characteristics along with the experimental challenges, strategies, and instrumentation that accompany this novel type of x-ray source. The main part of the article reviews the scientific achievements since the inception of LCLS in the five primary areas it serves: atomic, molecular, and optical physics; condensed matter physics; matter in extreme conditions; chemistry and soft matter, and biology.

  1. Photoacoustic imaging of clinical metal needle by a LED light source integrated transducer

    NASA Astrophysics Data System (ADS)

    Agano, Toshitaka; Sato, Naoto; Nakatsuka, Hitoshi; Kitagawa, Kazuo; Hanaoka, Takamitsu; Morisono, Koji; Shigeta, Yusuke; Tanaka, Chizuyo

    2016-03-01

    We have achieved penetration depth of 30mm by photoacoustic imaging system using LED light source integrated transducer to image a clinical metal needle inserted into a tissue mimicking phantom. We developed the transducer that integrated near-infrared LED array light source, which was connected to a photoacoustic imaging system which drove LED array light source and controlled photoacoustic data acquisition process. Conventionally solid-state laser has been used as the light source for photoacoustic imaging system. Because LED is diffused light source, laser safety glasses is not necessary, also inflexible fibers are not used to guide light close to a transducer, and we integrated LED light source inside the transducer, which became compact and practical size for conventional ultrasound equipment users. We made LED light source unit as detachable to the transducer easily, so wave-length of light can be selectable by changing the LED light source unit.

  2. Beacon system based on light-emitting diode sources for runways lighting

    NASA Astrophysics Data System (ADS)

    Montes, Mario González; Vázquez, Daniel; Fernandez-Balbuena, Antonio A.; Bernabeu, Eusebio

    2014-06-01

    New aeronautical ground lighting techniques are becoming increasingly important to ensure the safety and reduce the maintenance costs of the plane's tracks. Until recently, tracks had embedded lighting systems whose sources were based on incandescent lamps. But incandescent lamps have several disadvantages: high energy consumption and frequent breakdowns that result in high maintenance costs (lamp average life-time is ˜1500 operating hours) and the lamp's technology has a lack of new lighting functions, such as signal handling and modification. To solve these problems, the industry has developed systems based on light-emitting diode (LED) technology with improved features: (1) LED lighting consumes one tenth the power, (2) it improves preventive maintenance (an LED's lifetime range is between 25,000 and 100,000 hours), and (3) LED lighting technology can be controlled remotely according to the needs of the track configuration. LEDs have been in use for more than three decades, but only recently, around 2002, have they begun to be used as visual aids, representing the greatest potential change for airport lighting since their inception in the 1920s. Currently, embedded LED systems are not being broadly used due to the specific constraints of the rules and regulations of airports (beacon dimensions, power system technology, etc.). The fundamental requirements applied to embedded lighting systems are to be hosted on a volume where the dimensions are usually critical and also to integrate all the essential components for operation. An embedded architecture that meets the lighting regulations for airport runways is presented. The present work is divided into three main tasks: development of an optical system to optimize lighting according to International Civil Aviation Organization, manufacturing prototype, and model validation.

  3. UV light source adaptive sensing technology for flue gas measurement

    NASA Astrophysics Data System (ADS)

    Sun, Changku; Zhang, Chi; Sun, Bo; Liu, Bin; Wang, Peng

    2010-11-01

    The UV absorption spectrometry technique DOAS (Differential Optical Absorption Spectroscopy) has been widely used in continuous monitoring of flue gas, and has achieved good results. DOAS method is based on the basic law of light absorption--Lambert-Beer law. SO2, NOX are the principal component of the flue gas. These components are considered by DOAS method at the same time. And certain mathematical methods are used for concentrations measuring. The Continuous Emission Monitoring System (CEMS) based on the principle of DOAS mainly has two probe-styles present: in-situ probe-style and extractive probe-style. For the in-situ probe-style CEMS based on DOAS method, prolonged use for the UV light source, contaminated lens caused by floating oil and complex environment of the flue will all bring attenuation of the spectral intensity, it will affect the accuracy of measurement. In this article, an in-situ continuous monitoring system based on DOAS method is described, and a component adaptive sensing technology is proposed. By using this adaptive sensing technology, CEMS can adjust the integral time of the spectrometer according to the non-measuring attenuation of the light source intensity and automatically compensate the loss of spectral intensity. Under the laboratory conditions, the experiments for SO2, NO standard gas measurement using adaptive sensing technology is made. Many different levels of light intensity attenuation are considered in the experiments. The results show that the adaptive sensing technology can well compensate the non-measuring loss of spectral intensity. In the field measurement, this technology can well reduce the measurement error brought by attenuation of light intensity, compared with the handheld gas analyzer, the average error of concentration measurement is less than 2% FS(Full Scale).

  4. Development of a high-resolution soft x-ray (30--1500 eV) beamline at the Advanced Light Source and its use for the study of angle-resolved photoemission extended fine structure

    SciTech Connect

    Huff, Welcome Rex Anthony

    1996-02-01

    ALS Bending magnet beamline 9.3.2 is for high resolution spectroscopy, with circularly polarized light. Fixed included-angle SGM uses three gratings for 30--1500 eV photons; circular polarization is produced by an aperture for selecting the beam above or below the horizontal plane. Photocurrent from upper and lower jaws of entrance slit sets a piezoelectric drive feedback loop on the vertically deflecting mirror for stable beam. End station has a movable platform. With photomeission data from Stanford, structure of c(2x2)P/Fe(100) was determined using angle-resolved photoemission extended fine structure (ARPEFS). Multiple-scattering spherical-wave (MSSW) calculations indicate that P atoms adsorb in fourfold hollow sites 1.02A above the first Fe layer. Self-consistent-field Xα scattered wave calculation confirm that the Fe1-Fe2 space is contracted for S/Fe but not for P/Fe; comparison is made to atomic N and O on Fe(100). Final-state effects on ARPEFS curves used literature data from the S 1s and 2p core levels of c(2x2)S/Ni(001); a generalized Ramsauer-Townsend splitting is present in the 1s but not 2p data. An approximate method for analyzing ARPEFS data from a non-s initial state using only the higher-ℓ partial wave was tested successfully. ARPEFS data from clean surfaces were collected normal to Ni(111) (3p core levels) and 5° off-normal from Cu(111)(3s, 3p). Fourier transforms (FT) resemble adsorbate systems, showing backscattering signals from atoms up to 4 layers below emitters. 3p FTs show scattering from 6 nearest neighbors in the same crystal layer as the emitters. MSSW calulation indicate that Cu 3p photoemission is mostly d-wave. FTs also indicate double-scattering and single-scattering from laterally distant atoms; calculations indicate that the signal is dominated by photoemission from the first 2 crystal layers.

  5. Light source comprising a common substrate, a first led device and a second led device

    DOEpatents

    Choong, Vi-En

    2010-02-23

    At least one stacked organic or polymeric light emitting diode (PLEDs) devices to comprise a light source is disclosed. At least one of the PLEDs includes a patterned cathode which has regions which transmit light. The patterned cathodes enable light emission from the PLEDs to combine together. The light source may be top or bottom emitting or both.

  6. Preconceptual design requirements for the X-1 Advanced Radiation Source

    SciTech Connect

    Rochau, G.E.; Hands, J.A.; Raglin, P.S.; Ramirez, J.J.; Goldstein, S.A.; Cereghino, S.J.; MacLeod, G.

    1998-09-01

    The X-1 Advanced Radiation Source represents the next step in providing the US Department of Energy`s Stockpile Stewardship Program with the high-energy, large volume, laboratory x-ray source for the Radiation Effects Science and Simulation, Inertial Confinement Fusion, and Weapon Physics Programs. Advances in fast pulsed power technology and in z-pinch hohlraums on Sandia National Laboratories` Z Accelerator provide sufficient basis for pursuing the development of X-1. The X-1 plan follows a strategy based on scaling the 2 MJ x-ray output on Z via a 3-fold increase in z-pinch load current. The large volume (>5 cm{sup 3}), high temperature (>150 eV), temporally long (>10 ns) hohlraums are unique outside of underground nuclear weapon testing. Analytical scaling arguments and hydrodynamic simulations indicate that these hohlraums at temperatures of 230--300 eV will ignite thermonuclear fuel and drive the reaction to a yield of 200 to 1,000 MJ in the laboratory. X-1 will provide the high-fidelity experimental capability to certify the survivability and performance of non-nuclear weapon components in hostile radiation environments. Non-ignition sources will provide cold x-ray environments (<15 keV), and high yield fusion burn sources will provide high fidelity warm x-ray environments (15 keV--80 keV).

  7. The Use of Light-Emitting Diodes (LEDs) as Green and Red/Far-Red Light Sources in Plant Physiology.

    ERIC Educational Resources Information Center

    Jackson, David L.; And Others

    1985-01-01

    The use of green, red, and far-red light-emitting diodes (LEDs) as light sources for plant physiological studies is outlined and evaluated. Indicates that LED lamps have the advantage over conventional light sources in that they are lightweight, low-cost, portable, easily constructed, and do not require color filters. (Author/DH)

  8. Recent advances in laser-driven neutron sources

    NASA Astrophysics Data System (ADS)

    Alejo, A.; Ahmed, H.; Green, A.; Mirfayzi, S. R.; Borghesi, M.; Kar, S.

    2016-11-01

    Due to the limited number and high cost of large-scale neutron facilities, there has been a growing interest in compact accelerator-driven sources. In this context, several potential schemes of laser-driven neutron sources are being intensively studied employing laser-accelerated electron and ion beams. In addition to the potential of delivering neutron beams with high brilliance, directionality and ultra-short burst duration, a laser-driven neutron source would offer further advantages in terms of cost-effectiveness, compactness and radiation confinement by closed-coupled experiments. Some of the recent advances in this field are discussed, showing improvements in the directionality and flux of the laser-driven neutron beams.

  9. Application of semiconductor light sources for investigations of photochemical reactions

    NASA Astrophysics Data System (ADS)

    Landgraf, S.

    2001-09-01

    Semiconductor light sources, like laser diodes or ultrabright light emitting diodes, are widely used in optical spectroscopy. In this presentation an overview of applications in photochemistry is given. Since the beginning of the 1990s an increasing number of publications with the application of semiconductor light sources appeared. Three different techniques were used: single photon counting with short pulses, phase-modulation fluorometry using a conventional modulation spectrometer, or a lock-in amplifier. Using continuous wave laser diodes in the visible region, which are available from 690 to 630 nm (and, recently, down to 400 nm), a new compact fluorescence spectrometer was developed in our laboratory. Using the phase fluorometric method, measurements down to 100 ps are now possible. Values can be measured in steps of 10 ps with good reproducibility using a high-frequency signal generator and a GHz digital storage oscilloscope. Several investigations have been carried out applying this technique including time-resolved detection of crude oil as an example for possible practical applications.

  10. SYNCHROTRON RADIATION, FREE ELECTRON LASER, APPLICATION OF NUCLEAR TECHNOLOGY, ETC.: Study on the characteristics of linac based THz light source

    NASA Astrophysics Data System (ADS)

    Zhu, Xiong-Wei; Wang, Shu-Hong; Chen, Sen-Yu

    2009-10-01

    There are many methods based on linac for THz radiation production. As one of the options for the Beijing Advanced Light, an ERL test facility is proposed for THz radiation. In this test facility, there are 4 kinds of methods to produce THz radiation: coherent synchrotron radiation (CSR), synchrotron radiation (SR), low gain FEL oscillator, and high gain SASE FEL. In this paper, we study the characteristics of the 4 kinds of THz light sources.

  11. An Optically Stabilized Fast-Switching Light Emitting Diode as a Light Source for Functional Neuroimaging

    PubMed Central

    Wagenaar, Daniel A.

    2012-01-01

    Neuroscience research increasingly relies on optical methods for evoking neuronal activity as well as for measuring it, making bright and stable light sources critical building blocks of modern experimental setups. This paper presents a method to control the brightness of a high-power light emitting diode (LED) light source to an unprecedented level of stability. By continuously monitoring the actual light output of the LED with a photodiode and feeding the result back to the LED's driver by way of a proportional-integral controller, drift was reduced to as little as 0.007% per hour over a 12-h period, and short-term fluctuations to 0.005% root-mean-square over 10 seconds. The LED can be switched on and off completely within 100 s, a feature that is crucial when visual stimuli and light for optical recording need to be interleaved to obtain artifact-free recordings. The utility of the system is demonstrated by recording visual responses in the central nervous system of the medicinal leech Hirudo verbana using voltage-sensitive dyes. PMID:22238663

  12. An optically stabilized fast-switching light emitting diode as a light source for functional neuroimaging.

    PubMed

    Wagenaar, Daniel A

    2012-01-01

    Neuroscience research increasingly relies on optical methods for evoking neuronal activity as well as for measuring it, making bright and stable light sources critical building blocks of modern experimental setups. This paper presents a method to control the brightness of a high-power light emitting diode (LED) light source to an unprecedented level of stability. By continuously monitoring the actual light output of the LED with a photodiode and feeding the result back to the LED's driver by way of a proportional-integral controller, drift was reduced to as little as 0.007% per hour over a 12-h period, and short-term fluctuations to 0.005% root-mean-square over 10 seconds. The LED can be switched on and off completely within 100 μs, a feature that is crucial when visual stimuli and light for optical recording need to be interleaved to obtain artifact-free recordings. The utility of the system is demonstrated by recording visual responses in the central nervous system of the medicinal leech Hirudo verbana using voltage-sensitive dyes.

  13. A lighting assembly based on red and blue light-emitting diodes as a lighting source for space agriculture

    NASA Astrophysics Data System (ADS)

    Avercheva, Olga; Berkovich, Yuliy A.; Smolyanina, Svetlana; Bassarskaya, Elizaveta; Zhigalova, Tatiana; Ptushenko, Vasiliy; Erokhin, Alexei

    Light-emitting diodes (LEDs) are a promising lighting source for space agriculture due to their high efficiency, longevity, safety, and other factors. Assemblies based on red and blue LEDs have been recommended in literature, although not all plants show sufficient productivity in such lighting conditions. Adding of green LEDs proposed in some works was aimed at psychological support for the crew, and not at the improvement of plant growth. We studied the growth and the state of the photosynthetic apparatus in Chinese cabbage (Brassica chinensis L.) plants grown under red (650 nm) and blue (470 nm) light-emitting diodes (LEDs). Plants grown under a high-pressure sodium lamp (HPS lamp) were used as a control. The plants were illuminated with two photosynthetic photon flux levels: nearly 400 µE and about 100 µE. Plants grown under LEDs with 400 µE level, as compared to control plants, showed lower fresh weight, edible biomass, growth rate, and sugar content. The difference in fresh weight and edible biomass was even more pronounced in plants grown with 100 µE level; the data indicate that the adaptability of the test plants to insufficient lighting decreased. Under LEDs, we observed the decreasing of root growth and the absence of transition to the flowering stage, which points to a change in the hormonal balance in plants grown in such lighting conditions. We also found differences in the functioning of the photosynthetic apparatus and its reaction to a low lighting level. We have concluded that a lighting assembly with red and blue LEDs only is insufficient for the plant growth and productivity, and can bring about alterations in their adaptive and regulatory mechanisms. Further studies are needed to optimize the lighting spectrum for space agriculture, taking into account the photosynthetic, phototropic and regulatory roles of light. Using white LEDs or adding far-red and green LEDs might be a promising approach.

  14. Advances in audio source seperation and multisource audio content retrieval

    NASA Astrophysics Data System (ADS)

    Vincent, Emmanuel

    2012-06-01

    Audio source separation aims to extract the signals of individual sound sources from a given recording. In this paper, we review three recent advances which improve the robustness of source separation in real-world challenging scenarios and enable its use for multisource content retrieval tasks, such as automatic speech recognition (ASR) or acoustic event detection (AED) in noisy environments. We present a Flexible Audio Source Separation Toolkit (FASST) and discuss its advantages compared to earlier approaches such as independent component analysis (ICA) and sparse component analysis (SCA). We explain how cues as diverse as harmonicity, spectral envelope, temporal fine structure or spatial location can be jointly exploited by this toolkit. We subsequently present the uncertainty decoding (UD) framework for the integration of audio source separation and audio content retrieval. We show how the uncertainty about the separated source signals can be accurately estimated and propagated to the features. Finally, we explain how this uncertainty can be efficiently exploited by a classifier, both at the training and the decoding stage. We illustrate the resulting performance improvements in terms of speech separation quality and speaker recognition accuracy.

  15. Revised accident source terms for light-water reactors

    SciTech Connect

    Soffer, L.

    1995-02-01

    This paper presents revised accident source terms for light-water reactors incorporating the severe accident research insights gained in this area over the last 15 years. Current LWR reactor accident source terms used for licensing date from 1962 and are contained in Regulatory Guides 1.3 and 1.4. These specify that 100% of the core inventory of noble gases and 25% of the iodine fission products are assumed to be instantaneously available for release from the containment. The chemical form of the iodine fission products is also assumed to be predominantly elemental iodine. These assumptions have strongly affected present nuclear air cleaning requirements by emphasizing rapid actuation of spray systems and filtration systems optimized to retain elemental iodine. A proposed revision of reactor accident source terms and some im implications for nuclear air cleaning requirements was presented at the 22nd DOE/NRC Nuclear Air Cleaning Conference. A draft report was issued by the NRC for comment in July 1992. Extensive comments were received, with the most significant comments involving (a) release fractions for both volatile and non-volatile species in the early in-vessel release phase, (b) gap release fractions of the noble gases, iodine and cesium, and (c) the timing and duration for the release phases. The final source term report is expected to be issued in late 1994. Although the revised source terms are intended primarily for future plants, current nuclear power plants may request use of revised accident source term insights as well in licensing. This paper emphasizes additional information obtained since the 22nd Conference, including studies on fission product removal mechanisms, results obtained from improved severe accident code calculations and resolution of major comments, and their impact upon the revised accident source terms. Revised accident source terms for both BWRS and PWRS are presented.

  16. Boron-Containing Red Light-Emitting Phosphors And Light Sources Incorporating The Same

    DOEpatents

    Srivastava, Alok Mani; Comanzo, Holly Ann; Manivannan, Venkatesan

    2006-03-28

    A boron-containing phosphor comprises a material having a formula of AD1-xEuxB9O16, wherein A is an element selected from the group consisting of Ba, Sr, Ca, Mg, and combinations thereof; D is at least an element selected from the group consisting of rare-earth metals other than europium; and x is in the range from about 0.005 to about 0.5. The phosphor is used in a blend with other phosphors in a light source for generating visible light with a high color rendering index.

  17. Concepts for the PEP-X Light Source

    SciTech Connect

    Hettel, Robert; Bane, Karl; Bertsche, Kirk; Cai, Yunhai; Chao, Alex; Dolgashev, Valery; Fox, John; Huang, Xiaobiao; Huang, Zhirong; Mastorides, Themistoklis; Ng, Cho; Nosochkov, Yuri; Novokhatski, Alexander; Rabedeau, Thomas; Rivetta, Claudio; Safranek, James; Seeman, John; Stohr, Joachim; Stupakov, Gennady; Tantawi, Sami G.; Wang, Lanfa; /SLAC /Stanford U. /UCLA

    2010-08-26

    SSRL and SLAC groups are developing a long-range plan to transfer its evolving scientific programs from the SPEAR3 light source to a much higher performing photon source that would be housed in the 2.2-km PEP-II tunnel. While various concepts for the PEP-X light source are under consideration, including ultimate storage ring and ERL configurations, the present baseline design is a very low-emittance storage ring. A hybrid lattice has double bend achromat (DBA) cells in two of the six arcs that provide a total 30 straight sections for insertion device (ID) beam lines extending into two new experimental halls. The remaining arcs contain TME cells. Using 90 m of damping wigglers the horizontal emittance at 4.5 GeV would be 100 pm-rad with 1.5-A stored beam. PEP-X will produce photon beams having brightnesses near 10{sup 22} (ph/s/mm{sup 2}/mrad{sup 2}/0.1% BW) at 10 keV. Studies indicate that a 90-m undulator could have FEL gain and brightness enhancement at soft x-ray wavelengths with the stored beam. Crab cavities or other beam manipulation systems could be used to reduce bunch length or otherwise enhance photon emission properties. The present status of the design of PEP-X as a storage ring is presented.

  18. Ultraminiature Broadband Light Source and Method of Manufacturing Same

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret L. (Inventor); Collura, Joseph S. (Inventor); Helvajian, Henry (Inventor); Pocha, Michael D. (Inventor); Meyer, Glenn A. (Inventor); McConaghy, Charles F. (Inventor); Olsen, Barry L. (Inventor); Hansen, William W. (Inventor)

    2010-01-01

    An ultraminiature light source using a double-spiral shaped tungsten filament includes end contact portions which are separated to allow for radial and length-wise unwinding of the spiral. The double-spiral filament is spaced relatively far apart at the end portions thereof so that contact between portions of the filament upon expansion is avoided. The light ource is made by fabricating a double-spiral ultraminiature tungsten filament from tungsten foil and housing the filament in a ceramic package having a reflective bottom and a well wherein the filament is suspended. A vacuum furnace brazing process attaches the filament to contacts of the ceramic package. Finally, a cover with a transparent window is attached onto the top of the ceramic package by solder reflow in a second vacuum furnace process to form a complete hermetically sealed package.

  19. A 75 MHz light source for femtosecond stimulated raman microscopy.

    PubMed

    Ploetz, E; Marx, B; Klein, T; Huber, R; Gilch, P

    2009-10-12

    In femtosecond stimulated Raman microscopy (FSRM) a spectrally broad pulse (Raman probe) and a spectrally narrow pulse (Raman pump) interact in a sample and thereby generate a Raman spectrum of the focal volume. Here a novel light source for FSRM is presented. It consists of an 8-fs laser (repetition rate of 75 MHz) operating as Raman probe. A Yb(3+) based fiber amplifier generates the Raman pump light at 980 nm. The amplifier is seeded by the spectral wing of the 8-fs laser output which ensures synchronisation of pump and probe pulses. Spectral and temporal characteristics of these pulses are reported and simultaneous recording of broadband Raman spectra relying on these pulses is demonstrated.

  20. Overview of the Consortium for the Advanced Simulation of Light Water Reactors (CASL)

    NASA Astrophysics Data System (ADS)

    Kulesza, Joel A.; Franceschini, Fausto; Evans, Thomas M.; Gehin, Jess C.

    2016-02-01

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) was established in July 2010 for the purpose of providing advanced modeling and simulation solutions for commercial nuclear reactors. The primary goal is to provide coupled, higher-fidelity, usable modeling and simulation capabilities than are currently available. These are needed to address light water reactor (LWR) operational and safety performance-defining phenomena that are not yet able to be fully modeled taking a first-principles approach. In order to pursue these goals, CASL has participation from laboratory, academic, and industry partners. These partners are pursuing the solution of ten major "Challenge Problems" in order to advance the state-of-the-art in reactor design and analysis to permit power uprates, higher burnup, life extension, and increased safety. At present, the problems being addressed by CASL are primarily reactor physics-oriented; however, this paper is intended to introduce CASL to the reactor dosimetry community because of the importance of reactor physics modelling and nuclear data to define the source term for that community and the applicability and extensibility of the transport methods being developed.

  1. Characterization of germanium linear kinoform lenses at Diamond Light Source.

    PubMed

    Alianelli, L; Sawhney, K J S; Tiwari, M K; Dolbnya, I P; Stevens, R; Jenkins, D W K; Loader, I M; Wilson, M C; Malik, A

    2009-05-01

    The unprecedented brilliance achieved by third-generation synchrotron sources and the availability of improved optics have opened up new opportunities for the study of materials at the micrometre and nanometre scale. Focusing the synchrotron radiation to smaller and smaller beams is having a huge impact on a wide research area at synchrotrons. The key to the exploitation of the improved sources is the development of novel optics that deliver narrow beams without loss of brilliance and coherence. Several types of synchrotron focusing optics are successfully fabricated using advanced miniaturization techniques. Kinoform refractive lenses are being developed for hard X-ray beamlines, and the first test results at Diamond are discussed in this paper.

  2. Poster session: Fifth users meeting for the Advanced Photon Source

    SciTech Connect

    Not Available

    1992-11-01

    The Advanced Photon Source (APS), which is currently under construction as a national user facility at Argonne National Laboratory is a third-generation synchrotron x-ray source, one of only three in the world. It is expected to produce x-rays that are 10,000 times brighter than any currently produced elsewhere for use in research in a wide range of scientific areas. Users from industry, national laboratories, universities, and business will be able to come to the APS to conduct research either as members of Collaborative Access Teams (CATS) or as Independent Investigators. Principal users will be members of CATS, which will be building and operating all of the beamlines present in the first phase of APS beamline development. The first set of CATs has been selected through a competitive proposal process involving peer scientific review, thorough technical evaluation, and significant management oversight by the APS. This document is a compilation of posters presented at the Fifth Users Meeting for the Advanced Photon Source, held at Argonne National Laboratory on October 14--15, 1992. All CATs whose scientific cases were approved by the APS Proposal Evaluation Board are included. In addition, this document contains a poster from the Center for Synchrotron Radiation and Research and Instrumentation at the Illinois Institute of Technology.

  3. Spectral confocal reflection microscopy using a white light source

    NASA Astrophysics Data System (ADS)

    Booth, M.; Juškaitis, R.; Wilson, T.

    2008-08-01

    We present a reflection confocal microscope incorporating a white light supercontinuum source and spectral detection. The microscope provides images resolved spatially in three-dimensions, in addition to spectral resolution covering the wavelength range 450-650nm. Images and reflection spectra of artificial and natural specimens are presented, showing features that are not normally revealed in conventional microscopes or confocal microscopes using discrete line lasers. The specimens include thin film structures on semiconductor chips, iridescent structures in Papilio blumei butterfly scales, nacre from abalone shells and opal gemstones. Quantitative size and refractive index measurements of transparent beads are derived from spectral interference bands.

  4. Radiation properties of Turkish light source facility TURKAY

    NASA Astrophysics Data System (ADS)

    Nergiz, Zafer

    2015-09-01

    The synchrotron light source TURKAY, which is one of the sub-project of Turkish Accelerator Center (TAC), has been supported by Ministry of Development of Turkey since 2006. The facility is designed to generate synchrotron radiation (SR) in range 0.01-60 keV from a 3 GeV storage ring with a beam emittance of 0.51 nm rad. Synchrotron radiation will be produced from the bending magnets and insertion devices in the storage ring. In this paper design studies for possible devices to produce synchrotron radiation and radiation properties of these devices with TURKAY storage ring parameters are presented.

  5. Producing terahertz coherent synchrotron radiation at the Hefei Light Source

    NASA Astrophysics Data System (ADS)

    Xu, De-Rong; Xu, Hong-Liang; Shao, Yan

    2015-07-01

    This paper theoretically proves that an electron storage ring can generate coherent radiation in the THz region using a quick kicker magnet and an AC sextupole magnet. When the vertical chromaticity is modulated by the AC sextupole magnet, the vertical beam collective motion excited by the kicker produces a wavy spatial structure after a number of longitudinal oscillation periods. The radiation spectral distribution was calculated from the wavy bunch parameters at the Hefei Light Source (HLS). When the electron energy is reduced to 400 MeV, extremely strong coherent synchrotron radiation (CSR) at 0.115 THz should be produced. Supported by National Natural Science Foundation of China (11375176)

  6. Optical laser systems at the Linac Coherent Light Source

    DOE PAGES

    Minitti, Michael P.; Robinson, Joseph S.; Coffee, Ryan N.; ...

    2015-04-22

    Ultrafast optical lasers play an essential role in exploiting the unique capabilities of recently commissioned X-ray free-electron laser facilities such as the Linac Coherent Light Source (LCLS). Pump–probe experimental techniques reveal ultrafast dynamics in atomic and molecular processes and reveal new insights in chemistry, biology, material science and high-energy-density physics. This manuscript describes the laser systems and experimental methods that enable cutting-edge optical laser/X-ray pump–probe experiments to be performed at LCLS.

  7. Advanced light microscopy core facilities: Balancing service, science and career

    PubMed Central

    Hartmann, Hella; Reymann, Jürgen; Ansari, Nariman; Utz, Nadine; Fried, Hans‐Ulrich; Kukat, Christian; Peychl, Jan; Liebig, Christian; Terjung, Stefan; Laketa, Vibor; Sporbert, Anje; Weidtkamp‐Peters, Stefanie; Schauss, Astrid; Zuschratter, Werner; Avilov, Sergiy

    2016-01-01

    ABSTRACT Core Facilities (CF) for advanced light microscopy (ALM) have become indispensable support units for research in the life sciences. Their organizational structure and technical characteristics are quite diverse, although the tasks they pursue and the services they offer are similar. Therefore, throughout Europe, scientists from ALM‐CFs are forming networks to promote interactions and discuss best practice models. Here, we present recommendations for ALM‐CF operations elaborated by the workgroups of the German network of ALM‐CFs, German Bio‐Imaging (GerBI). We address technical aspects of CF planning and instrument maintainance, give advice on the organization and management of an ALM‐CF, propose a scheme for the training of CF users, and provide an overview of current resources for image processing and analysis. Further, we elaborate on the new challenges and opportunities for professional development and careers created by CFs. While some information specifically refers to the German academic system, most of the content of this article is of general interest for CFs in the life sciences. Microsc. Res. Tech. 79:463–479, 2016. © 2016 THE AUTHORS MICROSCOPY RESEARCH AND TECHNIQUE PUBLISHED BY WILEY PERIODICALS, INC. PMID:27040755

  8. Photoinjectors R&D for future light sources & linear colliders

    SciTech Connect

    Piot, P.; /Northern Illinois U. /Fermilab

    2006-08-01

    Linac-driven light sources and proposed linear colliders require high brightness electron beams. In addition to the small emittances and high peak currents, linear colliders also require spin-polarization and possibly the generation of asymmetric beam in the two transverse degrees of freedom. Other applications (e.g., high-average-power free-electron lasers) call for high duty cycle and/or (e.g., electron cooling) angular-momentum-dominated electron beams. We review ongoing R&D programs aiming at the production of electron beams satisfying these various requirements. We especially discuss R&D on photoemission electron sources (with focus on radiofrequency guns) along with the possible use of emittance-manipulation techniques.

  9. Broadband visible light source based on AllnGaN light emitting diodes

    DOEpatents

    Crawford, Mary H.; Nelson, Jeffrey S.

    2003-12-16

    A visible light source device is described based on a light emitting diode and a nanocluster-based film. The light emitting diode utilizes a semiconductor quantum well structure between n-type and p-type semiconductor materials on the top surface a substrate such as sapphire. The nanocluster-based film is deposited on the bottom surface of the substrate and can be derived from a solution of MoS.sub.2, MoSe.sub.2, WS.sub.2, and WSe.sub.2 particles of size greater than approximately 2 nm in diameter and less than approximately 15 nm in diameter, having an absorption wavelength greater than approximately 300 nm and less than approximately 650 nm.

  10. Advanced photon source experience with vacuum chambers for insertion devices

    SciTech Connect

    Hartog, P.D.; Grimmer, J.; Xu, S.; Trakhtenberg, E.; Wiemerslage, G.

    1997-08-01

    During the last five years, a new approach to the design and fabrication of extruded aluminum vacuum chambers for insertion devices was developed at the Advanced Photon Source (APS). With this approach, three different versions of the vacuum chamber, with vertical apertures of 12 mm, 8 mm, and 5 mm, were manufactured and tested. Twenty chambers were installed into the APS vacuum system. All have operated with beam, and 16 have been coupled with insertion devices. Two different vacuum chambers with vertical apertures of 16 mm and 11 mm were developed for the BESSY-II storage ring and 3 of 16 mm chambers were manufactured.

  11. Creep analysis of fuel plates for the Advanced Neutron Source

    SciTech Connect

    Swinson, W.F.; Yahr, G.T.

    1994-11-01

    The reactor for the planned Advanced Neutron Source will use closely spaced arrays of fuel plates. The plates are thin and will have a core containing enriched uranium silicide fuel clad in aluminum. The heat load caused by the nuclear reactions within the fuel plates will be removed by flowing high-velocity heavy water through narrow channels between the plates. However, the plates will still be at elevated temperatures while in service, and the potential for excessive plate deformation because of creep must be considered. An analysis to include creep for deformation and stresses because of temperature over a given time span has been performed and is reported herein.

  12. Penning plasma based simultaneous light emission source of visible and VUV lights

    NASA Astrophysics Data System (ADS)

    Vyas, G. L.; Prakash, R.; Pal, U. N.; Manchanda, R.; Halder, N.

    2016-06-01

    In this paper, a laboratory-based penning plasma discharge source is reported which has been developed in two anode configurations and is able to produce visible and VUV lights simultaneously. The developed source has simultaneous diagnostics facility using Langmuir probe and optical emission spectroscopy. The two anode configurations, namely, double ring and rectangular configurations, have been studied and compared for optimum use of the geometry for efficient light emissions and recording. The plasma is produced using helium gas and admixture of three noble gases including helium, neon, and argon. The source is capable to produce eight spectral lines for pure helium in the VUV range from 20 to 60 nm and total 24 spectral lines covering the wavelength range 20-106 nm for the admixture of gases. The large range of VUV lines is generated from gaseous admixture rather from the sputtered materials. The recorded spectrum shows that the plasma light radiations in both visible and VUV range are larger in double ring configuration than that of the rectangular configurations at the same discharge operating conditions. To clearly understand the difference, the imaging of the discharge using ICCD camera and particle-in-cell simulation using VORPAL have also been carried out. The effect of ion diffusion, metastable collision with the anode wall and the nonlinear effects are correlated to explain the results.

  13. The advanced neutron source safety approach and plans

    SciTech Connect

    Harrington, R.M. )

    1989-01-01

    The Advanced Neutron Source (ANS) is a user facility for all areas of neutron research proposed for construction at the Oak Ridge National Laboratory. The neutron source is planned to be a 350-MW research reactor. The reactor, currently in conceptual design, will belong to the United States Department of Energy (USDOE). The safety approach and planned elements of the safety program for the ANS are described. The safety approach is to incorporate USDOE requirements (which, by reference, include appropriate requirements from the United States Nuclear Regulatory Commission (USNRC) and other national and state regulatory agencies) into the design, and to utilize probabilistic risk assessment (PRA) techniques during design to achieve extremely low probability of severe core damage. The PRA has already begun and will continue throughout the design and construction of the reactor. Computer analyses will be conducted for a complete spectrum of accidental events, from anticipated events to very infrequent occurrences. 8 refs., 2 tabs.

  14. Man-machine interface builders at the Advanced Photon Source

    SciTech Connect

    Anderson, M.D.

    1991-01-01

    Argonne National Laboratory is constructing a 7-GeV Advanced Photon Source for use as a synchrotron radiation source in basic and applied research. The controls and computing environment for this accelerator complex includes graphical operator interfaces to the machine based on Motif, X11, and PHIGS/PEX. Construction and operation of the control system for this accelerator relies upon interactive interface builder and diagram/editor type tools, as well as a run-time environment for the constructed displays which communicate with the physical machine via network connections. This paper discusses our experience with several commercial CUI builders, the inadequacies found in these, motivation for the development of an application- specific builder, and design and implementation strategies employed in the development of our own Man-Machine Interface builder. 5 refs.

  15. Man-machine interface builders at the Advanced Photon Source

    SciTech Connect

    Anderson, M.D.

    1991-12-31

    Argonne National Laboratory is constructing a 7-GeV Advanced Photon Source for use as a synchrotron radiation source in basic and applied research. The controls and computing environment for this accelerator complex includes graphical operator interfaces to the machine based on Motif, X11, and PHIGS/PEX. Construction and operation of the control system for this accelerator relies upon interactive interface builder and diagram/editor type tools, as well as a run-time environment for the constructed displays which communicate with the physical machine via network connections. This paper discusses our experience with several commercial CUI builders, the inadequacies found in these, motivation for the development of an application- specific builder, and design and implementation strategies employed in the development of our own Man-Machine Interface builder. 5 refs.

  16. Radiation monitoring policy at the advanced light source

    SciTech Connect

    Donahue, R.; Heinzelman, K.; Perdue, G.

    1998-02-04

    When the accelerator first began operation it was decided that, until we had the necessary dosimetry data to decide otherwise, we would badge the entire worker and experimental population. Each person was issued a dosimetry badge that contained 4 TLD elements. Badges were processed on a monthly basis. After three years of analyzing a total of 65,000 TLD elements, the decision was made to modify the radiation monitoring policy at the ALS. Only those individuals in the workforce that have any potential for exposure, no matter how small, would be badged. Subsequently, DOE conducted an independent review of the ALS radiation monitoring and dosimetry program. This review concluded that the ALS program, if expanded as proposed, would be adequate under the 10 CFR 835 Rule to establish radiation exposures to an acceptable level of confidence. The review team recommended the ALS provide more comprehensive documentation on the basis for its radiation protection and monitoring program. This document describes the technical justification for that program.

  17. Annual meeting of the Advanced Light Source Users` Association

    SciTech Connect

    Not Available

    1994-03-01

    This report contains discussions on: Welcome to the annual meeting of the ALS User`s Association; overview of the ALS; the ALS into the 21st century; report from the DOE; scientific program at the ALS; plans for industrial use of the ALS; progress in beamline commissioning and overview of new projects; ALS user program; the fluorescent x-ray microprobe beamline at the ALS; the early days of x-ray optics; high-resolution soft x-ray spectroscopy; soft x-ray emission spectroscopy; x-ray dichroism; and application of VUV undulator beamline to chemical dynamics at the ALS.

  18. Environmental Science Program at the Advanced Light Source

    SciTech Connect

    Hubbard, Susan; Shuh, David; Nico, Peter

    2005-06-01

    Synchrotron Radiation (SR)-based techniques have become an essential and fundamental research tool in Molecular Environmental Science (MES) research. MES is an emerging scientific field that has largely evolved from research interactions at the U.S. Department of Energy (U.S. DOE) SR laboratories in response to the pressing need for understanding fundamental molecular-level chemical and biological processes that involve the speciation, properties, and behavior of contaminants, within natural systems. The role of SR-based investigations in MES and their impact on environmental problems of importance to society has been recently documented in Molecular Environmental Science: An Assessment of Research Accomplishment, Available Synchrotron Radiation Facilities, and Needs (EnviroSync, 2003).

  19. A multi-source portable light emitting diode spectrofluorometer.

    PubMed

    Obeidat, Safwan; Bai, Baolong; Rayson, Gary D; Anderson, Dean M; Puscheck, Adam D; Landau, Serge Y; Glasser, Tzach

    2008-03-01

    A portable luminescence spectrofluorometer weighing only 1.5 kg that uses multiple light emitting diodes (LEDs) as excitation sources was developed and evaluated. Excitation using a sequence of seven individual broad-band LED emission sources enabled the generation of excitation-emission spectra using a light weight (<1.5 kg) spectrometer. Limits of detection for rhodamine 6G, rhodamine B, and fluorescein were 2.9, 3.2, and 11.0 nM, respectively. Generation of excitation-emission matrices (EEMs) enabled the analysis of samples containing mixtures of rhodamine B and fluorescein. Buffered saline plant and animal feed extracts were also analyzed using this instrument. These samples included the woody plants Pistacia lentiscus (Evergreen pistache or Mastic) and Philyria latifolia, and the herbaceous species Medicago sativa (alfalfa), Trifolium spp. (clover), and a feed concentrate. Application of multi-way principal component analysis (MPCA) to the resulting three-dimensional data sets enabled discernment among these various diet constituents.

  20. Light source halos in night vision goggles: psychophysical assessments

    NASA Astrophysics Data System (ADS)

    Craig, Greg; Macuda, Todd; Thomas, Paul; Allison, Rob; Jennings, Sion

    2005-05-01

    Anecdotal reports by pilots flying with Night Vision Goggles (NVGs) in urban environments suggest that halos produced by bright light sources impact flight performance. The current study developed a methodology to examine the impact of viewing distance on perceived halo size. This was a first step in characterizing the subtle phenomenon of halo. Observers provided absolute size estimates of halos generated by a red LED at several viewing distances. Physical measurements of these halos were also recorded. The results indicated that the perceived halo linear size decreased as viewing distance was decreased. Further, the data showed that halos subtended a constant visual angle on the goggles (1°48", +/-7") irrespective of distance up to 75". This invariance with distance may impact pilot visual performance. For example, the counterintuitive apparent contraction of halo size with decreasing viewing distance may impact estimates of closure rates and of the spatial layout of light sources in the scene. Preliminary results suggest that halo is a dynamic phenomenon that requires further research to characterize the specific perceptual effects that it might have on pilot performance.

  1. SESAME -- A light source for the Middle East

    NASA Astrophysics Data System (ADS)

    Winick, Herman

    2012-02-01

    Developed under UNESCO and modelled on CERN, SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) is an international research centre in construction in Jordan, enabling world-class research while promoting peace through scientific cooperation. Its centerpiece, a new 2.5 GeV 3rd Generation Electron Storage Ring (133m circumference, 26nm-rad emittance, 12 places for insertion devices), will provide intense light from infra-red to hard X-rays. The Council (Bahrain, Cyprus, Egypt, Iran, Israel, Jordan, Pakistan, Palestinian Authority, Turkey), provides the annual budget. Concrete shielding is complete, and a staff of 21 is installing the refurbished 0.8 GeV BESS Y I injector system, a gift from Germany. The facility can serve 25 simultaneous experiments. Beamline equipment has been provided by Daresbury (UK), the Helmholtz Assoc. (Germany), the Swiss Light Source, LURE (France), the Univ. of Liverpool, Elettra (Italy) and US labs. Jordan has contributed 3.3M, in addition to a building and land. The EU has contributed 4.8M. Commitments confirmed by Members look set to provide most of 35M needed to complete construction of the ring and 3 beamlines. A training program has been underway since 2000. See www.sesame.org.jo

  2. Follow-up fuel plate stability experiments and analyses for the Advanced Neutron Source

    SciTech Connect

    Swinson, W.F.; Battiste, R.L.; Luttrell, C.R.; Yahr, G.T.

    1993-11-01

    The reactor for the planned Advanced Neutron Source uses closely spaced plates cooled by heavy water flowing through narrow channels. Two sets of tests were performed on the upper and lower fuel plates for the structural response of the fuel plates to the required high coolant flow velocities. This report contains the data from the second round of tests. Results and conclusions from all of the tests are also included in this report. The tests were done using light water on full-scale epoxy models, and through model theory, the results were related to the prototype plates, which are aluminum-clad aluminum/uranium silicide involute-shaped plates.

  3. Advancements in sensing and perception using structured lighting techniques :an LDRD final report.

    SciTech Connect

    Novick, David Keith; Padilla, Denise D.; Davidson, Patrick A. Jr.; Carlson, Jeffrey J.

    2005-09-01

    This report summarizes the analytical and experimental efforts for the Laboratory Directed Research and Development (LDRD) project entitled ''Advancements in Sensing and Perception using Structured Lighting Techniques''. There is an ever-increasing need for robust, autonomous ground vehicles for counterterrorism and defense missions. Although there has been nearly 30 years of government-sponsored research, it is undisputed that significant advancements in sensing and perception are necessary. We developed an innovative, advanced sensing technology for national security missions serving the Department of Energy, the Department of Defense, and other government agencies. The principal goal of this project was to develop an eye-safe, robust, low-cost, lightweight, 3D structured lighting sensor for use in broad daylight outdoor applications. The market for this technology is wide open due to the unavailability of such a sensor. Currently available laser scanners are slow, bulky and heavy, expensive, fragile, short-range, sensitive to vibration (highly problematic for moving platforms), and unreliable for outdoor use in bright sunlight conditions. Eye-safety issues are a primary concern for currently available laser-based sensors. Passive, stereo-imaging sensors are available for 3D sensing but suffer from several limitations : computationally intensive, require a lighted environment (natural or man-made light source), and don't work for many scenes or regions lacking texture or with ambiguous texture. Our approach leveraged from the advanced capabilities of modern CCD camera technology and Center 6600's expertise in 3D world modeling, mapping, and analysis, using structured lighting. We have a diverse customer base for indoor mapping applications and this research extends our current technology's lifecycle and opens a new market base for outdoor 3D mapping. Applications include precision mapping, autonomous navigation, dexterous manipulation, surveillance and

  4. Pseudo-single-bunch with adjustable frequency: a new operation mode for synchrotron light sources.

    PubMed

    Sun, C; Portmann, G; Hertlein, M; Kirz, J; Robin, D S

    2012-12-28

    We present the concept and results of pseudo-single-bunch (PSB) operation--a new operational mode at the advanced light source--that can greatly expand the capabilities of synchrotron light sources to carry out dynamics and time-of-flight experiments. In PSB operation, a single electron bunch is displaced transversely from the other electron bunches using a short-pulse, high-repetition-rate kicker magnet. Experiments that require light emitted only from a single bunch can stop the light emitted from the other bunches using a collimator. Other beam lines will only see a small reduction in flux due to the displaced bunch. As a result, PSB eliminates the need to schedule multibunch and timing experiments during different running periods. Furthermore, the time spacing of PSB pulses can be adjusted from milliseconds to microseconds with a novel "kick-and-cancel" scheme, which can significantly alleviate complications of using high-power choppers and substantially reduce the rate of sample damage.

  5. A study of an advanced confined linear energy source

    NASA Technical Reports Server (NTRS)

    Anderson, M. C.; Heidemann, W. B.

    1971-01-01

    A literature survey and a test program to develop and evaluate an advanced confined linear energy source were conducted. The advanced confined linear energy source is an explosive or pyrotechnic X-Cord (mild detonating fuse) supported inside a confining tube capable of being hermetically sealed and retaining all products of combustion. The energy released by initiation of the X-Cord is transmitted through the support material to the walls of the confining tube causing an appreciable change in cross sectional configuration and expansion of the tube. When located in an assembly that can accept and use the energy of the tube expansion, useful work is accomplished through fracture of a structure, movement of a load, reposition of a pin, release of a restraint, or similar action. The tube assembly imparts that energy without release of debris or gases from the device itself. This facet of the function is important to the protection of men or equipment located in close proximity to the system during the time of function.

  6. Plasma-Based Studies on 4th Generation Light Sources

    SciTech Connect

    Lee, R W; Baldis, H A; Cauble, R C; Landen, O L; Wark, J S; Ng, A; Rose, S J; Lewis, C; Riley, D; Gauthier, J-C; Audebert, P

    2000-11-28

    The construction of a short pulse tunable x-ray laser source will be a watershed for plasma-based and warm dense matter research. The areas we will discuss below can be separated broadly into warn dense matter (WDM) research, laser probing of near solid density plasmas, and laser-plasma spectroscopy of ions in plasmas. The area of WDM refers to that part of the density-temperature phase space where the standard theories of condensed matter physics and/or plasma statistical physics are invalid. Warm dense matter, therefore, defines a region between solids and plasmas, a regime that is found in planetary interiors, cool dense stars, and in every plasma device where one starts from a solid, e.g., laser-solid matter produced plasma as well as all inertial fusion schemes. The study of dense plasmas has been severely hampered by the fact that laser-based methods have been unavailable. The single most useful diagnostic of local plasma conditions, e.g., the temperature (T{sub e}), the density (n{sub e}), and the ionization (Z), has been Thomson scattering. However, due to the fact that visible light will not propagate at electron densities, n{sub e}, {ge} 10{sup 22} cm{sup -3} implies dense plasmas can not be probed. The 4th generation sources, LCLS and Tesla will remove these restrictions. Laser-based plasma spectroscopic techniques have been used with great success to determine the line shapes of atomic transitions in plasmas, study the population kinetics of atomic systems embedded in plasmas, and look at redistribution of radiation. However. the possibilities end for plasmas with n{sub e} {ge} 10{sup 22} since light propagation through the medium is severely altered by the plasma. The entire field of high Z plasma kinetics from laser produced plasma will then be available to study with the tunable source.

  7. Terahertz Light Source and User Area at FACET

    SciTech Connect

    Wu, Z.; Li, S.Z.; Litos, M.; Fisher, A.D.; Hogan, M.J.; /SLAC

    2011-11-08

    FACET at SLAC provides high charge, high peak current, low emittance electron beam that is bunched at THz wavelength scale during its normal operation. A THz light source based coherent transition radiation (CTR) from this beam would potentially be the brightest short-pulse THz source ever constructed. Efforts have been put into building this photon source together with a user area, to provide a platform to utilize this unique THz radiation for novel nonlinear and ultrafast phenomena researches and experiments. Being a long-time underutilized portion of the electromagnetic spectrum, terahertz (100 GHz {approx} 10 THz) spectral range is experiencing a renaissance in recent years, with broad interests from chemical and biological imaging, material science, telecommunication, semiconductor and superconductor research, etc. Nevertheless, the paucity of THz sources especially strong THz radiation hinders both its commercial applications and nonlinear processes research. FACET - Facilities for Accelerator science and Experimental Test beams at SLAC - provides 23 GeV electron beam with peak currents of {approx} 20 kA that can be focused down to 100 {mu}m{sup 2} transversely. Such an intense electron beam, when compressed to sub-picosecond longitudinal bunch length, coherently radiates high intensity EM fields well within THz frequency range that are orders of magnitude stronger than those available from laboratory tabletop THz sources, which will enable a wide variety of THz related research opportunities. Together with a description of the FACET beamline and electron beam parameters, this paper will report FACET THz radiation generation via coherent transition radiation and calculated photon yield and power spectrum. A user table is being set up along the THz radiation extraction sites, and equipped with various signal diagnostics including THz power detector, Michelson interferometer, sample stages, and sets of motorized optical components. This setup will also be

  8. Proceedings of the Advanced Photon Source renewal workshop.

    SciTech Connect

    Gibson, J. M.; Mills, D. M.; Kobenhavns Univ.; Northwestern Univ.; Stony Brook Univ.; Univ. of Pennsylvania; Notre Dame Univ.; Univ. of Chicago; Univ. of Connecticut; Diamond Light Source Ltd.; Univ. of Wisconsin at Madison; North Dakota State Univ.; Washington State Univ.; ORNL; Univ. of Illinois; NIH

    2008-12-01

    Beginning in March 2008, Advanced Photon Source (APS) management engaged users, facility staff, the distinguished members of the APS Scientific Advisory Committee, and other outside experts in crafting a renewal plan for this premier synchrotron x-ray research facility. It is vital that the investment in the APS renewal begin as soon as possible in order to keep this important U.S. facility internationally competitive. The APS renewal plan encompasses innovations in the beamlines and the x-ray source that are needed for major advances in science - advances that promise to further extend the impact of x-ray science on energy research, technology development, materials innovation, economic competitiveness, health, and far-reaching fundamental knowledge. A planning milestone was the APS Renewal Workshop held on October 20-21, 2008. Organized by the APS Renewal Steering Committee, the purpose of the workshop was to provide a forum where leading researchers could present the broad outlines of forward-looking plans for science at the APS in all major disciplines serviced by x-ray techniques. Two days of scientific presentations, discussions, and dialogue involved more than 180 scientists representing 41 institutions. The scientific talks and breakout/discussion sessions provided a forum for Science Team leaders to present the outlines of forward-looking plans for experimentation in all the major scientific disciplines covered by photon science. These proceedings comprise the reports from the Science Teams that were commissioned by the APS Renewal Steering Committee, having been edited by the Science Teams after discussion at the workshop.

  9. Light-emitting diodes as a radiation source for plants

    NASA Technical Reports Server (NTRS)

    Bula, R. J.; Morrow, R. C.; Tibbitts, T. W.; Barta, D. J.; Ignatius, R. W.; Martin, T. S.

    1991-01-01

    Development of a more effective radiation source for use in plant-growing facilities would be of significant benefit for both research and commercial crop production applications. An array of light-emitting diodes (LEDs) that produce red radiation, supplemented with a photosynthetic photon flux (PPF) of 30 micromoles s-1 m-2 in the 400- to 500-nm spectral range from blue fluorescent lamps, was used effectively as a radiation source for growing plants. Growth of lettuce (Lactuca sativa L. Grand Rapids') plants maintained under the LED irradiation system at a total PPF of 325 micromoles s-1 m-2 for 21 days was equivalent to that reported in the literature for plants grown for the same time under cool-white fluorescent and incandescent radiation sources. Characteristics of the plants, such as leaf shape, color, and texture, were not different from those found with plants grown under cool-white fluorescent lamps. Estimations of the electrical energy conversion efficiency of a LED system for plant irradiation suggest that it may be as much as twice that published for fluorescent systems.

  10. State of Art in the Science and Technology of Electrical Discharge Light Sources

    NASA Astrophysics Data System (ADS)

    Zissis, Georges; Rouffet, Jean-Baptiste

    Light is vital for life: Light sources play an indispensable role to daily life of any Human being. Our World cannot be conceived without light. Quality of life, health and, somehow, urban security related with traffic and crime prevention measures depend on light and on its quality. The lighting industry is an important economic factor in Europe, USA and many Asiatic Countries. All in all, lighting is an important socio-economic factor and lighting system development should be an integral part of any Sustainable Development and of any program of improvement of Quality of Life. This presentation provides an overview of the present state of research in the science and technology of light sources. Existing technologies and future challenges for the lighting industry will be presented. To better understanding the light source technology an part of this presentation will be devoted to the physics of light sources.

  11. Light-assisted drying (LAD) of small volume biologics: a comparison of two IR light sources

    NASA Astrophysics Data System (ADS)

    Young, Madison A.; Van Vorst, Matthew; Elliott, Gloria D.; Trammell, Susan R.

    2016-03-01

    Protein therapeutics have been developed to treat diseases ranging from arthritis and psoriasis to cancer. A challenge in the development of protein-based drugs is maintaining the protein in the folded state during processing and storage. We are developing a novel processing method, light-assisted drying (LAD), to dehydrate proteins suspended in a sugar (trehalose) solution for storage at supra-zero temperatures. Our technique selectively heats the water in small volume samples using near-IR light to speed dehydration which prevents sugar crystallization that can damage embedded proteins. In this study, we compare the end moisture content (EMC) as a function of processing time of samples dried with two different light sources, Nd:YAG (1064 nm) and Thulium fiber (1850 nm) lasers. EMC is the ratio of water to dry weight in a sample and the lower the EMC the higher the possible storage temperature. LAD with the 1064 and 1850 nm lasers yielded 78% and 65% lower EMC, respectively, than standard air-drying. After 40 minutes of LAD with 1064 and 1850 nm sources, EMCs of 0.27+/-.27 and 0.15+/-.05 gH2O/gDryWeight were reached, which are near the desired value of 0.10 gH2O/gDryWeight that enables storage in a glassy state without refrigeration. LAD is a promising new technique for the preparation of biologics for anhydrous preservation.

  12. A nano-graphite cold cathode for an energy-efficient cathodoluminescent light source.

    PubMed

    Obraztsov, Alexander N; Kleshch, Victor I; Smolnikova, Elena A

    2013-01-01

    The development of new types of light sources is necessary in order to meet the growing demands of consumers and to ensure an efficient use of energy. The cathodoluminescence process is still under-exploited for light generation because of the lack of cathodes suitable for the energy-efficient production of electron beams and appropriate phosphor materials. In this paper we propose a nano-graphite film material as a highly efficient cold cathode, which is able to produce high intensity electron beams without energy consumption. The nano-graphite film material was produced by using chemical vapor deposition techniques. Prototypes of cathodoluminescent lamp devices with a construction optimized for the usage of nano-graphite cold cathodes were developed, manufactured and tested. The results indicate prospective advantages of this type of lamp and the possibility to provide advanced power efficiency as well as enhanced spectral and other characteristics.

  13. Artificial light at night advances avian reproductive physiology

    PubMed Central

    Dominoni, Davide; Quetting, Michael; Partecke, Jesko

    2013-01-01

    Artificial light at night is a rapidly increasing phenomenon and it is presumed to have global implications. Light at night has been associated with health problems in humans as a consequence of altered biological rhythms. Effects on wild animals have been less investigated, but light at night has often been assumed to affect seasonal cycles of urban dwellers. Using light loggers attached to free-living European blackbirds (Turdus merula), we first measured light intensity at night which forest and city birds are subjected to in the wild. Then we used these measurements to test for the effect of light at night on timing of reproductive physiology. Captive city and forest blackbirds were exposed to either dark nights or very low light intensities at night (0.3 lux). Birds exposed to light at night developed their reproductive system up to one month earlier, and also moulted earlier, than birds kept under dark nights. Furthermore, city birds responded differently than forest individuals to the light at night treatment, suggesting that urbanization can alter the physiological phenotype of songbirds. Our results emphasize the impact of human-induced lighting on the ecology of millions of animals living in cities and call for an understanding of the fitness consequences of light pollution. PMID:23407836

  14. Development of liquid-jet laser-produced plasma light source for EUV lithography

    NASA Astrophysics Data System (ADS)

    Abe, Tamotsu; Suganuma, Takashi; Imai, Yousuke; Sugimoto, Yukihiko; Someya, Hiroshi; Hoshino, Hideo; Soumagne, Georg; Komori, Hiroshi; Mizoguchi, Hakaru; Endo, Akira; Toyoda, Koichi

    2003-06-01

    The Extreme UV Lithography System Development Association (EUVA) was established in Japan in May 2002 and is supported by the Ministry of Economy, Trade and Industry (METI). EUVA started the light soruce development in September 2002. This development is done by the assocaition members Gigaphoton, Ushio, Komatsu, Canon, Nikon, the National Institute of Advanced Industrial Sciecne and Technology (AIST) and several Japanese universities. The target of the four-year project is the development of a EUV light source with 10W clean focus point power. For the end of the fiscal year 2003 the development of a 4W EUV light source (clean focus point power) is planned. Both, Laser-Produced-Plasma (LPP) and Discharge-Produced-Plasma (DPP) EUV light sources are investigated at first. Our group at the EUVA Hiratsuka R&D Center is working on LPP sources. We are currently focusing on the development of a driver laser and a liquid Xenon plasma target. The laser is a Nd:YAG MOPA (Master Oscillator and Power Amplifier) system oscillating at 1064 nm. Average power, repetition rate and pulse duration of the laser system are 500 Watt, 10 kHa and 30nsec, respectively. The Xenon liquefication system operates at a maximum pressure of 5MPa and a temperature range between 160 K and 190 K. The pressure inside the vacuum chamber is below 0.1Pa during system operation. This paper presents the current status of the EUV system component development as well as first experimental results of generated EUV radiation.

  15. Nuclear methods of analysis in the advanced neutron source

    SciTech Connect

    Robinson, L.; Dyer, F.F.

    1994-12-31

    The Advanced Neutron Source (ANS) research reactor is presently in the conceptual design phase. The thermal power of this heavy water cooled and moderated reactor will be about 350 megawatts. The core volume of 27 liter is designed to provide the optimum neutron fluence rate for the numerous experimental facilities. The peak thermal neutron fluence rate is expected to be slightly less than 10{sup 20} neutrons/m{sup 2}s. In addition to the more than 40 neutron scattering stations, there will be extensive facilities for isotope production, material irradiation and analytical chemistry including neutron activation analysis (NAA) and a slow positron source. The highlight of this reactor will be the capability that it will provide for conducting research using cold neutrons. Two cryostats containing helium-cooled liquid deuterium will be located in the heavy water reflector tank. Each cryostat will provide low-temperature neutrons to researchers via numerous guides. A hot source with two beam tubes and several thermal beam tubes will also be available. The NAA facilities in the ANS will consist of seven pneumatic tubes, one cold neutron guide for prompt gamma-ray neutron activation analysis (PGNAA), and one cold neutron slanted guide for neutron depth profiling (NDP). In addition to these neutron interrogation systems, a gamma-ray irradiation facility for materials testing will be housed in a spent fuel storage pool. This paper will provide detailed information regarding the design and use of these various experimental systems.

  16. LED based powerful nanosecond light sources for calibration systems of deep underwater neutrino telescopes

    NASA Astrophysics Data System (ADS)

    Lubsandorzhiev, B. K.; Poleshuk, R. V.; Shaibonov, B. A. J.; Vyatchin, Y. E.

    2009-04-01

    Powerful nanosecond light sources based on LEDs have been developed for use in calibration systems of deep underwater neutrino telescopes. The light sources use either matrixes of ultra bright blue InGaN LEDs or new generation high power blue LEDs. It is shown that such light sources have light yield of up to 1010-1012 photons per pulse with very fast light emission kinetics. The developed light sources are currently used in a number of astroparticle physics experiments, namely: the lake Baikal neutrino experiment, the TUNKA EAS experiment, etc.

  17. National Synchrotron Light Source II storage ring vacuum systems

    SciTech Connect

    Hseuh, Hsiao-Chaun; Hetzel, Charles; Leng, Shuwei; Wilson, King; Xu, Huijuan; Zigrosser, Douglas

    2016-04-05

    The National Synchrotron Light Source II, completed in 2014, is a 3-GeV synchrotron radiation (SR) facility at Brookhaven National Laboratory and has been in steady operation since. With a design electron current of 500 mA and subnanometer radians horizontal emittance, this 792-m circumference storage ring is providing the highest flux and brightness x-ray beam for SR users. Also, the majority of the storage ring vacuum chambers are made of extruded aluminium. Chamber sections are interconnected using low-impedance radiofrequency shielded bellows. SR from the bending magnets is intercepted by water-cooled compact photon absorbers resided in the storage ring chambers. Finally, this paper presents the design of the storage ring vacuum system, the fabrication of vacuum chambers and other hardware, the installation, the commissioning, and the continuing beam conditioning of the vacuum systems.

  18. Supercontinuum as a light source for miniaturized endoscopes.

    PubMed

    Lu, M K; Lin, H Y; Hsieh, C C; Kao, F J

    2016-09-01

    In this work, we have successfully implemented supercontinuum based illumination through single fiber coupling. The integration of a single fiber illumination with a miniature CMOS sensor forms a very slim and powerful camera module for endoscopic imaging. A set of tests and in vivo animal experiments are conducted accordingly to characterize the corresponding illuminance, spectral profile, intensity distribution, and image quality. The key illumination parameters of the supercontinuum, including color rendering index (CRI: 72%~97%) and correlated color temperature (CCT: 3,100K~5,200K), are modified with external filters and compared with those from a LED light source (CRI~76% & CCT~6,500K). The very high spatial coherence of the supercontinuum allows high luminosity conduction through a single multimode fiber (core size~400μm), whose distal end tip is attached with a diffussion tip to broaden the solid angle of illumination (from less than 10° to more than 80°).

  19. Supercontinuum as a light source for miniaturized endoscopes

    PubMed Central

    Lu, M. K.; Lin, H. Y.; Hsieh, C. C.; Kao, F. J.

    2016-01-01

    In this work, we have successfully implemented supercontinuum based illumination through single fiber coupling. The integration of a single fiber illumination with a miniature CMOS sensor forms a very slim and powerful camera module for endoscopic imaging. A set of tests and in vivo animal experiments are conducted accordingly to characterize the corresponding illuminance, spectral profile, intensity distribution, and image quality. The key illumination parameters of the supercontinuum, including color rendering index (CRI: 72%~97%) and correlated color temperature (CCT: 3,100K~5,200K), are modified with external filters and compared with those from a LED light source (CRI~76% & CCT~6,500K). The very high spatial coherence of the supercontinuum allows high luminosity conduction through a single multimode fiber (core size~400μm), whose distal end tip is attached with a diffussion tip to broaden the solid angle of illumination (from less than 10° to more than 80°). PMID:27699102

  20. A Next Generation Light Source Facility at LBNL

    SciTech Connect

    Corlett, J.N.; Austin, B.; Baptiste, K.M.; Byrd, J.M.; Denes, P.; Donahue, R.; Doolittle, L.; Falcone, R.W.; Filippetto, D.; Fournier, S.; Li, D.; Padmore, H.A.; Papadopoulos, C.; Pappas, C.; Penn, G.; Placidi, M.; Prestemon, S.; Prosnitz, D.; Qiang, J.; Ratti, A.; Reinsch, M.; Sannibale, F.; Schlueter, R.; Schoenlein, R.W.; Staples, J.W.; Vecchione, T.; Venturini, M.; Wells, R.; Wilcox, R.; Wurtele, J.; Charman, A.; Kur, E.; Zholents, A.A.

    2011-03-23

    The Next Generation Light Source (NGLS) is a design concept, under development at LBNL, for a multibeamline soft x-ray FEL array powered by a ~;;2 GeV superconducting linear accelerator, operating with a 1 MHz bunch repetition rate. The CW superconducting linear accelerator is supplied by a high-brightness, highrepetition- rate photocathode electron gun. Electron bunches are distributed from the linac to the array of independently configurable FEL beamlines with nominal bunch rates up to 100 kHz in each FEL, and with even pulse spacing. Individual FELs may be configured for EEHG, HGHG, SASE, or oscillator mode of operation, and will produce high peak and average brightness x-rays with a flexible pulse format, with pulse durations ranging from sub-femtoseconds to hundreds of femtoseconds.