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DISPERSION TOLERANCE CALCULATION FOR NSLS-II.

Description: In this paper we discuss the effect on the emittance of the residual dispersion in the insertion devices. The dispersion in the straights could be generated by the lattice error, trim dipole, and insertion device. The effect on the emittance is examined, and the dispersion tolerances are given for the NSLS-11.
Date: June 25, 2007
Creator: LIN,F. & GUO, W.
Partner: UNT Libraries Government Documents Department

Operations with the digital orbit feedback system in the NSLS x-ray ring

Description: The digital filtering and eigenvector decomposition-based orbit correction is performed by two dedicated HP 742/743 rt micros which communicate with Motorola CPU based orbit-measuring and orbit-correction systems. The correction algorithm in the DFbk was orthogonalized with respect of the analog global harmonic feedback. Operational results concerning improvements in the noise suppression at low frequencies and especially in the dc drift as well as in the orbit stability are shown. Efforts are underway to improve the resolution of the orbit measuing system and the sampling rate using 16 bit 400 kHz ADC`s which will allow orbit sampling with high resolution at 4 kHz frequency.
Date: May 1, 1996
Creator: Bozoki, E.; Rammamorthy, S.; Singh, O.; Tang, Y. & Friedman, A.
Partner: UNT Libraries Government Documents Department

Global DC closed orbit correction experiment on the NSLS x-ray ring

Description: In this note are described the global DC closed orbit correction experiments conducted on the X-ray ring at National Synchrotron Light Source (NSLS). The beam response matrix, defined as beam motion at BPM locations per unit kick by corrector magnets, was measured and then inverted using the technique of singular value decomposition (SVD). The product of the inverted matrix and the difference orbit gives the incremental kick strengths necessary to correct the orbit. As a result, the r.m.s. orbit error around the ring was reduced from 208 {mu}m to 61 {mu}m.
Date: September 15, 1992
Creator: Chung, Y.; Decker, G. & Evans, K.
Partner: UNT Libraries Government Documents Department

High Resolution Upgrade for Core-level Photoemission Spectroscopy

Description: Upgraded the high resolution core-level photoemission beamline U4A at the National Synchrotron Light Source (NSLS) so that it has higher resolution ({approx}30-50 meV) over a broader spectral range (10-200 eV) than is currently available at any other photoemission beamline at NSLS. Such an upgraded beamline will prove to be extremely useful in new studies of bimetallic systems and semiconductor interfaces.
Date: August 31, 1999
Creator: Madey, T. E.
Partner: UNT Libraries Government Documents Department

Status of NSLS-II Storage Ring Vacuum Systems

Description: National Synchrotron Light Source II (NSLS-II), being constructed at Brookhaven National Laboratory, is a 3-GeV, high-flux and high- brightness synchrotron radiation facility with a nominal current of 500 mA. The storage ring vacuum system will have extruded aluminium chambers with ante-chamber for photon fans and distributed NEG strip pumping. Discrete photon absorbers will be used to intercept the un-used bending magnet radiation. In-situ bakeout will be implemented to achieve fast conditioning during initial commissioning and after interventions.
Date: May 4, 2009
Creator: Doom,L.; Hseuh,H.; Ferreira, M.; Longo, C.; Ravindranath, V.; Settepani, P. et al.
Partner: UNT Libraries Government Documents Department

REQUIREMENTS AND GUIDELINES FOR NSLS EXPERIMENTAL BEAM LINE VACUUM SYSTEMS-REVISION B.

Description: Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are used at various beam line locations so that the monochromator, mirror box or sample chamber may be used in a helium atmosphere or rough vacuum. The window separates ring vacuum from the environment of the downstream beam line components. The stored beam lifetime in the storage rings and the maintenance of desirable reflection properties of optical surfaces depend upon hydrocarbon-free, ultra-high vacuum systems. Storage ring vacuum systems will operate at pressures of {approximately} 1 x 10{sup {minus}10} Torr without beam and {approximately} 1 x 10{sup {minus}9} Torr with beam. Systems are free of hydrocarbons in the sense that no pumps, valves, etc. containing organics are used. Components are all-metal, chemically cleaned and bakeable. To the extent that beam lines share a common vacuum with the storage ring, the same criteria will hold for beam line components. The design philosophy for NSLS beam lines is ...
Date: May 1, 1999
Creator: FOERSTER,C.
Partner: UNT Libraries Government Documents Department

Polarization Studies of CdZnTe Detectors Using Synchrotron X-Ray Radiation.

Description: New results on the effects of small-scale defects on the charge-carrier transport in single-crystal CdZnTe (CZT) material were produced. We conducted detailed studies of the role of Te inclusions in CZT by employing a highly collimated synchrotron x-ray radiation source available at Brookhaven's National Synchrotron Light Source (NSLS). We were able to induce polarization effects by irradiating specific areas with the detector. These measurements allowed the first quantitative comparison between areas that are free of Te inclusions and those with a relatively high concentration of inclusions. The results of these polaration studies will be reported.
Date: July 1, 2007
Creator: Camarda, G. S.; Bolotnikov, A. E.; Cui, Y.; Hossain, A. & James, R. B.
Partner: UNT Libraries Government Documents Department

VARIABLE MOMENTUM COMPACTION LATTICE STUDIES.

Description: The VUV storage ring at the National Synchrotron Light Source was used to study the impact of changes in the momentum compaction factors over a large range from positive to negative values. Changes in bunch length and synchrotron tune were measured versus current and RF parameters for these different lattices. By controlling both the first and second-order momentum compaction factors, a lattice was developed in which a pair of alpha buckets was created within the energy aperture of the vacuum chamber and beam was stored simultaneously in both buckets.
Date: March 29, 1999
Creator: KRAMER,S. & MURPHY,J.B.
Partner: UNT Libraries Government Documents Department

Time-resolved far-infrared experiments at the National Synchrotron Light Source. Final report

Description: A facility for time-resolved infrared and far-infrared spectroscopy has been built and commissioned at the National Synchrotron Light Source. This facility permits the study of time dependent phenomena over a frequency range from 2-8000cm{sup {minus}1} (0.25 meV-1 eV). Temporal resolution is approximately 200 psec and time dependent phenomena in the time range out to 100 nsec can be investigated.
Date: October 12, 1999
Creator: Tanner, D.B.; Reitze, D.H. & Carr, G.L.
Partner: UNT Libraries Government Documents Department

Upgrade of NSLS timing system

Description: We report on the progress of the new NSLS timing system. There are three types of requirements for NSLS timing system: clocks, synchronization and trigger circuits. All ring revolution frequency clocks are generated using ECL and high speed TTL logic. The synchronization circuits allows to fill both storage rings with any bunch pattern. The triggers are generated by using commercially available digital delay generators. The delay unit`s outputs are ultrastable, with a resolution of 5 ps, and are programmed by computer via IEEE 488 interface. The block diagrams, description of all major timing components and the present status are provided in this paper.
Date: May 1, 1995
Creator: Singh, O.; Ramamoorthy, S.; Sheehan, J. & Smith, J.
Partner: UNT Libraries Government Documents Department

VARIABLE MOMENTUM COMPACTION LATTICE STUDIES.

Description: The VUV storage ring at the National Synchrotron Light Source was used to study the impact of changes in the momentum compaction factors over a large range from positive to negative values. Changes in bunch length and synchrotron tune were measured versus current and RF parameters for these different lattices. By controlling both the first and second-order momentum compaction factors, a lattice was developed in which a pair of alpha buckets was created within the energy aperture of the vacuum chamber and beam was stored simultaneously in both buckets.
Date: March 29, 1999
Creator: KRAMER,S. & MURPHY,J.B.
Partner: UNT Libraries Government Documents Department

Research by industry at the National Synchrotron Light Source

Description: 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.).
Date: May 1995
Partner: UNT Libraries Government Documents Department

NSLS-II Beam Diagnostics Overview

Description: A new 3rd generation light source (NSLS-II) is in the early stages of construction at Brookhaven National Laboratory. The NSLS-II facility will provide ultra high brightness and flux with exceptional beam stability. It presents several challenges for diagnostics and instrumentation, related to the extremely small emittance. In this paper, we present an overview of all planned instrumentation systems, results from research and development activities; and then focus on other challenging aspects.
Date: May 4, 2009
Creator: Singh,O.; Alforque, R.; Bacha, B.; Blednykh, A.; Cameron, P.; Cheng, W. et al.
Partner: UNT Libraries Government Documents Department

NSLS-II Booster Acceptance Studies

Description: The NSLS-II is a state of the art 3 GeV synchrotron light source being developed at BNL. The injection system will consist of a 200 MeV linac and a 3 GeV booster synchrotron. The injection system must supply 7.3 nC every minute to satisfy the top off requirements. A large booster acceptance is necessary to have a high booster injection efficiency and alleviate the requirements on the linac gun. We also anticipate transverse stacking of bunches in the booster to increase the amount of charge that can be delivered. We present studies of the anticipated booster stay clear and the ramifications for injection efficiency and transverse stacking.
Date: May 4, 2009
Creator: Fliller III,R.; Guo, W.; Heese, R.; Li, Y. & Shaftan, T.
Partner: UNT Libraries Government Documents Department

Overview of Beam Instrumentation and Diagnostics for the NSLS-II Project

Description: A new, ultra-bright 3rd generation light source, the NSLS-II Project, is planned to be built at Brookhaven National Laboratory. The light source being developed will have unprecedently small beam horizontal emittance and will provide the radiation sources with a brightness of 3 x 10{sup 21} photons/sec/0.1%BW/mm{sup 2}/mrad{sup 2}. In this paper we present the detailed specifications and a comprehensive description of the planned beam instrumentation system and the first results of the ongoing instrumentation R&D activities on beyond state-of-the-art subsystems.
Date: May 4, 2008
Creator: Singh,O.
Partner: UNT Libraries Government Documents Department

DESIGN OF BEAM TRANSFER LINES FOR THE NSLS II

Description: The NSLS-II light source which is a proposed facility to be built at Brookhaven National Laboratory utilizes two synchrotron accelerator rings: the booster and the Storage ring (SR). Designing the NSLS-11 injector we considered two options for the booster layout, where the rings either (a) share the same tunnel, but placed at different horizontal planes or (b) booster is located in a separate building. The booster which accepts beam from the linac, accelerates the electron beam to an energy of 3.0 GeV and the beam is extracted to the Booster to Storage Ring (BtS) transport line which transports the beam and injects it into the SR ring. The design procedure for each of the two options of the BtS line and other details about the optics and the magnetic elements of the line are presented in this paper.
Date: June 25, 2007
Creator: TSOUPAS,N.; ROSE, J.; PINAYEV, I.; SHAFTAN, T. & STELMACH, C.
Partner: UNT Libraries Government Documents Department

High Brightness Electron Beam Studies at the NSLS SDL

Description: Experimental optimization of electron beam brightness at the NSLS SDL is reported in this paper. Using a high quantum efficiency (QE) Mg metal cathode and the S-band BNL-type RF gun, we have systematically studied electron beams transverse and longitudinal emittance. The measured thermal emittance for the Mg cathode is 0.85{+-}0.04 mm-mrad/mm, which contradicts the current thermal emittance model. For a 50 pC beam, measured normalized transverse and longitudinal RMS emittance are 0.6 mm-mrd and 5.2 ps-keV, respectively. The smallest projected transverse emittance observed for a 20 pC charge is 0.15 {+-} 0.02 mm-mrad.
Date: May 4, 2009
Creator: Qian,H.; Hidaka, Y.; Murphy, J. B.; Podobedov, B.; Seletskiy, S.; Shen, Y. et al.
Partner: UNT Libraries Government Documents Department

Developing EnviroSuite Resources at the National Synchrotron Light Source

Description: The objective of Brookhaven National Laboratory's EnviroSuite Initiative is to develop the facilities, user support infrastructure, and techniques necessary to conduct world-class molecular environmental science research at the NSLS. This is intended to benefit the research of ERSD-supported scientists, both through direct access and assistance and through the indirect benefits of a broader network of environmental scientists as collaborators and users. Much of the EnviroSuite research involves close collaboration with members of the Center for Environmental Molecular Science (CEMS), an EMSI based at BNL and nearby Stony Brook University and jointly supported by ERSD (Project 1023761, P. Kalb) and NSF. This offers unique opportunities to benefit from both national laboratory facilities and university resources. Other collaborators, from around the US and the world, investigate various aspects of the underlying molecular-scale processes in complex natural systems. In general, synchrotron techniques are ideal for studying the molecular-scale structures, chemical/physical interactions, and transformations that govern the macroscopic properties and processes (e.g. transport, bioavailability) of contaminants in the environment. These techniques are element-specific, non-destructive, and sensitive to the very low concentrations found in real-world samples.
Date: June 1, 2006
Creator: Northrup, Paul; Fitts, Jeffrey; Fuhrmann, Mark & Kalb, Paul
Partner: UNT Libraries Government Documents Department

NSLS IN-VACUUM UNDULATORS AND MINI-BETA STRAIGHTS.

Description: We review the work carried out in the X13 R&D Straight Section of the NSLS X-Ray Ring on small gap in-vacuum undulators (IVUNs). Then we discuss: (1) plans to replace the pure permanent magnet undulator in X13 by a hybrid design providing stronger magnetic fields, enhancing the tunability of the device; (2) plans to install hybrid IVUNs in the two RF straights of the X-Ray Ring, increasing the number of insertion devices in the XRay Ring to eight; (3) the possibility of reducing the vertical beta function in the X13 straight from 0.33 m down to 0.16 m. This reduction in beta function would allow us to decrease the usable undulator gap from 3mm down to 2mm, further increasing the tuning range.
Date: June 18, 2001
Creator: RAKOWSKY,G.; LYNCH,D.; BLUM,E.B. & KRINSKY,S.
Partner: UNT Libraries Government Documents Department

LONGITUDINAL MEASUREMENTS AND SIMULATIONS OF STRETCHED BUNCHES IN THE NSLS VUV RING.

Description: Certain longitudinal instabilities in the stretched bunches of the National Synchrotron Light Source Vacuum Ultra-Violet ring are described and simulated using a code for the integration of the Vlasov-Fokker-Planck equation (these proceedings). Results for the microwave instability driven by broadband impedance, instability driven by high-Q radio-frequency modes, and response functions in stretched bunches, are compared with measurements from the ring.
Date: June 18, 2001
Creator: TOWNE,N.
Partner: UNT Libraries Government Documents Department