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Indispensable tool

Description: Synchrotron radiation has become an indispensable research tool for a growing number of scientists in a seemingly ever expanding number of disciplines. We can thank the European Synchrotron Research Facility (ESRF) in Grenoble for taking an innovative step toward achieving the educational goal of explaining the nature and benefits of synchrotron radiation to audiences ranging from the general public (including students) to government officials to scientists who may be unfamiliar with x-ray techniques and synchrotron radiation. ESRF is the driving force behind a new CD-ROM playable on both PCs and Macs titled Synchrotron light to explore matter. Published by Springer-Verlag, the CD contains both English and French versions of a comprehensive overview of the subject.
Date: August 10, 2001
Creator: Robinson, Arthur
Partner: UNT Libraries Government Documents Department

A week of SRI 2003 in San Francisco

Description: The Eighth International Conference on Synchrotron Radiation (SRI 2003) ended its August 25-28 run at the Yerba Buena Center for the Arts in San Francisco with almost as many in attendance as at the beginning. The steady attendance was surely a tribute to the quality of the program and the excitement it generated among the more than 700 registrants who gathered for four days of plenary talks, parallel sessions, and posters, as well as facility tours of the ALS and SSRL on August 29.
Date: September 29, 2003
Creator: Robinson, Art
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Date: August 14, 2002
Creator: Robinson, Arthur L.
Partner: UNT Libraries Government Documents Department

Very high power THz radiation sources

Description: We report the production of high power (20 watts average, {approx} 1 Megawatt peak) broadband THz light based on coherent emission from relativistic electrons. Such sources are ideal for imaging, for high power damage studies and for studies of non-linear phenomena in this spectral range. We describe the source, presenting theoretical calculations and their experimental verification. For clarity we compare this source to one based on ultrafast laser techniques.
Date: October 31, 2002
Creator: Carr, G.L.; Martin, Michael C.; McKinney, Wayne R.; Jordan, K.; Neil, George R. & Williams, G.P.
Partner: UNT Libraries Government Documents Department

Sixth International Conference on X-ray Microscopy

Description: More than 180 participants from around the world crowded the Clark Kerr Campus of the University of California, Berkeley, from August 1-6, 1999 for the Sixth International Conference on X-Ray Microscopy (XRM99). Held every three years since 1983, the XRM conferences have become the primary international forum for the presentation and discussion of advances in high-spatial-resolution x-ray imaging and applications (including the use of x-ray spectroscopic and analytical techniques) in biological and medical sciences, environmental and soil sciences, and materials and surface sciences.
Date: August 23, 1999
Creator: Robinson, Arthur L.
Partner: UNT Libraries Government Documents Department


Description: A status report on the revitalization of the NSLS VUV ring will be presented, concentrating on three areas: (1) the four infrared ports (U2A/B, U4IR, U10A/B, and U12IR), (2) conversion of out-of-date toroidal grating monochromators to spherical grating type (U4A, U7A, and U12A), and (3) new insertion device beamlines (U5UA and U13UB). All of these beamlines were designed (new ones) or upgraded (old ones) to serve a specific scientific need represented by the PRTs (both NSLS and non-NSLS based) involved. Therefore, an overview of the scientific programs served by these new beamlines will be given, as well as a summary of the beamline optical designs and operating performance.
Date: October 13, 1999
Creator: HULBERT,S.L.
Partner: UNT Libraries Government Documents Department

Coherent synchrotron radiation and stability of a short bunch in a compact storage ring

Description: It should be possible to observe coherent synchrotron radiation at millimeter wavelengths in a compact electron storage ring, provided that the bunch can be made sufficiently short. On the other hand, for a short bunch the radiation reaction is so strong that it could cause a longitudinal instability if the current exceeded some threshold. This might cause bunch lengthening, and cut off or reduce the coherent radiation. Using wake fields from simple models of the vacuum chamber, the authors estimate the threshold current for a proposed upgrade of the Brookhaven small x-ray light source, SXLS-Phase 1.
Date: June 1, 1995
Creator: Warnock, R.L. & Bane, K.
Partner: UNT Libraries Government Documents Department

12th Annual ALS Users' Association Meeting

Description: Science took the front seat as 219 Advanced Light Source (ALS) users and staff gathered on Monday and Tuesday, October 18 and 19 for the twelfth annual users' meeting. The bulk of the meeting was dedicated to reports on science at the ALS. Packed into two busy days were 31 invited oral presentations and 80 submitted poster presentations, as well as time to visit 24 vendor booths. The oral sessions were dedicated to environmental science, chemical dynamics, biosciences, magnetic materials, and atomic and molecular science. In addition, there was an ALS highlights session that emphasized new results and a session comprising highlights from the young scientists who will carry the ALS into the future.
Date: December 17, 1999
Creator: Robinson, Arthur L.
Partner: UNT Libraries Government Documents Department

Workshop on detectors for synchrotron radiation

Description: Forefront experiments in many scientific areas for which synchrotron sources provide sufficient flux are nonetheless hindered because detectors cannot collect data fast enough, do not cover sufficiently solid angle, or do no have adequate resolution. Overall, the synchrotron facilities, each of which represents collective investments from funding agencies and user institutions ranging from many hundreds of millions to more than a billion dollars, are effectively significantly underutilized. While this chronic and growing problem plagues facilities around the world, it is particularly acute in the United States, where detector research often has to ride on the coat tails of explicitly science-oriented projects. As a first step toward moving out of this predicament, scientists from the U.S. synchrotron facilities held a national workshop in Washington, DC, on October 30-31, 2000. The Workshop on Detectors for Synchrotron Research aimed to create a national ''roadmap'' for development of synchrotron-radiation detectors.
Date: November 22, 2000
Creator: Robinson, Arthur L.
Partner: UNT Libraries Government Documents Department

Looking Back at International Synchrotron Radiation Instrumentation

Description: With the 11th International Synchrotron Radiation Instrumentation coming up in July 2012 in Lyons, France, we thought it might be of interest to our readers to review all the past meetings in this series. We thank Denny Mills of the APS, Argonne for putting the list together. Prior to these larger meetings, and in the early days, facilities held their own meetings similar to the user meetings of today. However, the meeting held at ACO in Orsay, France in 1977 was the first such meeting with an international flavor and so it is on the list. However it is not counted as number 1 since it was agreed way back to start the numbering with the 1982 DESY meeting. The 2005 USA National Meeting scheduled at CAMD in Baton Rouge had to be canceled due to Hurricane Katrina. It was ultimately held in 2007, with the CLS hosted meeting the following year. And a personal note from the magazine - Synchrotron Radiation News was born at the 1987 meeting in Madison, Wisconsin with a proposal that was put to a special session of the meeting organized by Susan Lord. Initial proposals were to model it after the CERN Courier, but it soon adopted its own distinct flavor.
Date: March 1, 2012
Creator: Williams, Gwyn
Partner: UNT Libraries Government Documents Department


Description: We discuss the possibility of using synchrotron radiation to form electron rings having a very high electric field to hold the ions inside the ring. The formulas describing bow the energy and the dimension of the ring change under the effect of synchrotron radiation are derived, and a numerical example is given.
Date: May 13, 1970
Creator: Pellegrini, C.
Partner: UNT Libraries Government Documents Department

Some Aspects of the Two Beam Performance of DCI

Description: The results of beam-beam simulations that model DCI operating as an e{sup +}e{sup -} collider are reported. The simulation techniques, including a new procedure for incorporating synchrotron radiation, are described. Phase advance errors between the interaction points explain the beam-beam limit at the operating point q{sub x} = q{sub y} = 0.725 (q denotes the fractional part of the tune). The effects of radiation damping are also studied near that operating point. Simulation and experiments disagree in a second operating region, q{sub x} = q{sub y} {approx} 0.795, indicating additional physics outside the scope of our model.
Date: September 1, 1991
Creator: Krishnagopal, S. & Siemann, R.H.
Partner: UNT Libraries Government Documents Department

Enabling instrumentation and technology for 21st century light sources

Description: 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.
Date: June 1, 2010
Creator: Byrd, J.M.; Shea, T.J.; Denes, P.; Siddons, P.; Attwood, D.; Kaertner, F. et al.
Partner: UNT Libraries Government Documents Department

An Isochronous Lattice for PEP

Description: With e{sup +}e{sup -} storage rings operating in a quasi-isochronous mode, it might be possible to produce short bunches with length {sigma}{sub z} < 1 cm. The unique characteristics of the short bunches could then be utilized for synchrotron radiation applications or colliders with mm-scale {beta}*. In principle, the design of a quasi-isochronous storage ring is relatively straight-forward, but experimental studies with electron storage rings in this configuration have not been carried out. The purpose of this paper is to demonstrate that an isochronous lattice design is compatible with PEP given a minimum of hardware modifications.
Date: April 1, 1991
Creator: Corbett, W.J.; Donald, M.H.R. & Garren, A.A.
Partner: UNT Libraries Government Documents Department

Wake fields and energy spread for the ERHIC ERL

Description: Wake fields in high-current ERLs can cause significant beam quality degradations. Here we summarize effects of coherent synchrotron radiation, resistive wall, accelerating cavities and wall roughness for ERL parameters of the eRHIC project. A possibility of compensation of such correlated energy spread is also presented. An emphasis in the discussion is made on the suppression of coherent synchrotron radiation due to shielding and a possible reduction of wall roughness effects for realistic surfaces.
Date: October 16, 2011
Creator: V., Fedotov A.; Kayran&#44 & D.
Partner: UNT Libraries Government Documents Department

A Vlasov solver for collective effects in particle accerators

Description: Integration techniques based on Lie algebraic methods have been successfully used in beam transport codes for particle accelerators. Generally these methods have been applied to problems of single-particle beam dynamics. Here we present an application of Lie algebraic techniques to the development of a Vlasov solver suitable for problems of beam transport in the presence of non-negligible particle self-fields. The solver we discuss is suitable for modelling a variety of collective effects that may arise at high current. In particular, we consider the case of coherent synchrotron radiation effects in magnetic bunch compressors which can cause instabilities limiting performance of high current accelerators.
Date: February 1, 2009
Creator: Migliorati, M.; Schiavi, A.; Dattoli, G. & Venturini, M.
Partner: UNT Libraries Government Documents Department

Keck Observations of the 2002-2003 Jovian Ring Plane Crossing

Description: We present new observations of Jupiter's ring system at a wavelength of 2.2 {micro}m obtained with the 10-m W. M. Keck telescopes on three nights during a ring plane crossing: UT 19 December 2002, and 22 and 26 January 2003. We used conventional imaging, plus adaptive optics on the last night. Here we present detailed radial profiles of the main ring, halo and gossamer rings, and interpret the data together with information extracted from radio observations of Jupiter's synchrotron radiation. The main ring is confined to a 800-km-wide annulus between 128,200 and 129,000 km, with a {approx} 5000 km extension on the inside. The normal optical depth is 8 x 10{sup -6}, 15% of which is provided by bodies with radii a {approx}> 5 cm. These bodies are as red as Metis. Half the optical depth, {tau} {approx} 4 x 10{sup -6}, is attributed to micron-sized dust, and the remaining {tau} {approx} 3 x 10{sup -6} to grains tens to hundreds of {micro}m in size. The inward extension consists of micron-sized (a {approx}< 10 {micro}m) dust, which probably migrates inward under Poynting-Robertson drag. The inner limit of this extension falls near the 3:2 Lorentz resonance (at orbital radius r = 122,400 km), and coincides with the outer limit of the halo. The gossamer rings appear to be radially confined, rather than broad sheets of material. The Amalthea ring is triangularly shaped, with a steep outer dropoff over {approx} 5000 km, extending a few 1000 km beyond the orbit of Amalthea, and a more gradual inner dropoff over 15,000-20,000 km. The inner edge is near the location of the synchronous orbit. The optical depth in the Amalthea ring is {approx} 5 x 10{sup -7}, up to 20% of which is comprised of macroscopic material. The optical depth in the Thebe ring ...
Date: November 29, 2007
Creator: de Pater, I; Showalter, M R & Macintosh, B A
Partner: UNT Libraries Government Documents Department

Coherent synchrotron radiation: Theory and experiments

Description: Our understanding of the generation of coherent synchrotron radiation in magnetic bending systems and its impact on beam dynamics has grown considerably over the past few years. The search for understanding has brought a number of surprises, all related to the complexity of the fully self-consistent problem. Herein I survey the associated phenomenology, theory, and experiments while emphasizing important subtleties that have recently been uncovered. I conclude by speculating on courses of future investigations that may prove fruitful.
Date: July 19, 2002
Creator: Bohn, Courtland L.
Partner: UNT Libraries Government Documents Department

Improving and extending performance at synchrotron radiation facilities

Description: Synchrotron radiation facilities around the world have now matured through three generations. The latest facilities have all met or exceeded their design specifications and are learning how to cope with the ever more demanding requests of the user community, especially concerning beam stability. The older facilities remain competitive by extending the unique features of their design, and by developing novel insertion devices. In this paper we survey the beam characteristics achieved at third-generation sources and explore the improvements made at earlier generation facilities.
Date: May 1, 1997
Creator: Jackson, A.
Partner: UNT Libraries Government Documents Department